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Using heart rate (HR) measurements to detect mental stress in naturalistic settings is hampered by the physiological impact of hemodynamic and metabolic demands. Correcting HR for these demands can help isolate fluctuations in HR associated with psychosocial stress responses, a concept termed additional heart rate (aHR). This study examined whether adding predictors for posture, activity type, and lagged movement intensity for the prolonged impact of physical activity (PA) improved aHR estimation across various manipulations of mental stress, posture, and PA in a controlled laboratory environment (n = 197). Accelerometer signals were used to obtain the movement intensity and to classify posture and activity type. Posture, activity type, and lagged movement intensity each led to a significant improvement in HR estimation, as measured by adjusted R2 and root mean squared error. However, HR was overestimated during quiet sitting. The aHR, computed as the difference between observed and predicted HR, generally underestimated observed task‐baseline reactivity but was sensitive to individual differences in reactivity to mental stressors. Between‐subject correlations of aHR with task‐baseline reactivity ranged from 0.62 to 0.93 across conditions. On a within‐subject level, the ability of aHR to differentiate between exposure to physical stress and mental stress was limited (recall = 0.32, precision = 0.31), but better than that of observed HR (recall = 0.02, precision = 0.02). Future research should explore the potential of this novel aHR estimation method in differentiating physical and mental demands on HR in daily life, and its predictive value for health outcomes. [ABSTRACT FROM AUTHOR]

The neurovisceral integration model proposes that information flows bidirectionally between the brain and the heart via the vagus nerve, indexed by vagally mediated heart rate variability (vmHRV). Voluntary reduction in breathing rate (slow‐paced breathing, SPB, 5.5 Breathing Per Minute (BPM)) can enhance vmHRV. Additionally, prefrontal transcranial direct current stimulation (tDCS) can modulate the excitability of the prefrontal region and influence the vagus nerve. However, research on the combination of SPB and prefrontal tDCS to increase vmHRV and other cardiac (heart rate (HR) and blood pressure) and peripheral (skin conductance) indices is scarce. We hypothesized that the combination of 20 min of SPB and prefrontal tDCS would have a greater effect than each intervention in isolation. Hence, 200 participants were divided into four groups: active tDCS with SPB, active tDCS with 15 BPM breathing, sham tDCS with SPB, and sham tDCS with 15 BPM breathing. Regardless of the tDCS condition, the 5.5 BPM group showed a significant increase in vmHRV over 20 minutes and significant decreases in HR at the first and second 5‐min epochs of the intervention. Regardless of breathing condition, the active tDCS group exhibited higher HR at the fourth 5‐min epoch of the intervention than the sham tDCS group. No other effects were observed. Overall, SPB is a robust technique for increasing vmHRV, whereas prefrontal tDCS may produce effects that counteract those of SPB. More research is necessary to test whether and how SPB and neuromodulation approaches can be combined to improve cardiac vagal tone. This study explored, for the first time, the temporal course of physical (slow‐paced breathing, SPB) and neuromodulation (prefrontal tDCS) interventions to enhance cardiac vagal tone. Through a well‐sampled between‐subjects sham‐controlled design, this study found that SPB has a very rapid impact on increasing vagally mediated HRV and decreasing HR and blood pressure. Prefrontal tDCS, on the contrary, has a slower effect, mainly increasing heart rate suggesting more sympathetic arousal. Unexpectedly, the combination did not yield beneficial results. [ABSTRACT FROM AUTHOR]

Resting heart rate may confer risk for cardiovascular disease (CVD) and other adverse cardiovascular events. While the brainstem's autonomic control over heart rate is well established, less is known about the regulatory role of higher level cortical and subcortical brain regions, especially in humans. This study sought to characterize the brain networks that predict variation in prevailing heart rate in otherwise healthy adults. We used machine learning approaches designed for complex, high‐dimensional data sets, to predict variation in instantaneous heart period (the inter‐heartbeat‐interval) from whole‐brain hemodynamic signals measured by fMRI. Task‐based and resting‐state fMRI, as well as peripheral physiological recordings, were taken from two data sets that included extensive repeated measurements within individuals. Our models reliably predicted instantaneous heart period from whole‐brain fMRI data both within and across individuals, with prediction accuracies being highest when measured within‐participants. We found that a network of cortical and subcortical brain regions, many linked to visceral motor and visceral sensory processes, were reliable predictors of variation in heart period. This adds to evidence on brain–heart interactions and constitutes an incremental step toward developing clinically applicable biomarkers of brain contributions to CVD risk. Using whole‐brain fMRI data, we reliably predicted instantaneous heart period within and across individuals from the activity of a network of cortical and subcortical brain regions, many linked to visceral motor and visceral sensory processes. This adds to existing evidence on brain–heart interactions and constitutes a step toward developing clinically applicable biomarkers of brain contributions to CVD risk. [ABSTRACT FROM AUTHOR]

Concealed information test (CIT) has been utilized for long to perform single measurements. The combination of multiple measures outperforms single measures because of the diverse cognitive processes they reflect and the reduction in random errors facilitated by multiple measures. To further explore the performance of the CIT with multiple measurements, 57 participants were recruited and randomly assigned into guilty and innocent groups. Subsequently, simultaneously recorded reaction time (RT), skin conductance responses (SCRs), heart rate (HR), and neuroimaging data were collected from functional near‐infrared spectroscopy (fNIRS) to detect participants' concealed information in a standard CIT. The results demonstrated that all indicators including RT (area under the curve (AUC) = 0.87), SCRs (AUC = 0.79), HR (AUC = 0.78), and fNIRS (channel 8, AUC = 0.85) could differentiate guilty and innocent groups. Importantly, the use of multiple indicators achieved higher detection efficiency (AUC = 0.96) compared to the use of any single indicator. These results illustrate the effectiveness and feasibility of integrating multiple indicators for concealed information detection in CIT. [ABSTRACT FROM AUTHOR]

Transcranial magnetic stimulation (TMS) is pivotal in the field of major depressive disorder treatment. Due to its unsatisfied response rate, an increasing number of researchers have turned their attention towards optimizing TMS site localization. Since the influence of TMS in reducing heart rate (HR) offers insights into its regulatory impact on the autonomic nervous system, a novel approach, called neurocardiac‐guided TMS (NCG–TMS), has been proposed to pinpoint the brain region eliciting the maximal individual reduction in HR as a personalized optimal stimulation target. The present study intends to systematically explore the effects of stimulation frequency, left and right hemispheres, stimulation positions, and individual differences on HR modulation using the NCG–TMS method. In experiment 1, low‐frequency TMS was administered to 30 subjects, and it was found that low‐frequency NCG–TMS significantly downregulated HR, with more significant effects in the right hemisphere than in the left hemisphere and the prefrontal cortex than in other brain areas. In experiment 2, high‐frequency NCG–TMS stimulation was administered to 30 subjects, showing that high‐frequency NCG–TMS also downregulated HR and had the greatest modulatory effect in the right prefrontal region. Simultaneously, both experiments revealed sizeable individual variability in the optimal stimulation site, which in turn validated the feasibility of the NCG–TMS method. In conclusion, the present experiments independently replicated the effect of NCG–TMS, provided an effect of high‐/low‐frequency TMS stimulation to downregulate HR, and identified a right lateralization of the HR modulation effect. This study independently validated the neuro‐cardiac‐guided transcranial magnetic stimulation (TMS) technique through high‐frequency and low‐frequency TMS. The findings not only unveiled the group‐level heart rate regulatory effects of the right prefrontal cortex but also uncovered individual differences in regulatory responses. These results offer novel theoretical support for the personalized clinical application of TMS in modulating the autonomic nervous system. [ABSTRACT FROM AUTHOR]

The ability to flexibly transition between defensive states is crucial for adaptive responding in life‐threatening situations. Potentially threatening situations typically induce a sustained feeling of apprehension in association with hypervigilance, while acute threat is usually characterized by an intense and transient response to cope with the imminent danger. While potential and acute threat states have traditionally been viewed as mutually exclusive, this distinction is being challenged by a growing body of evidence suggesting a more complex interplay during simultaneous activation of these states. However, the interaction between potential and acute threat on a psychophysiological level remains elusive. To fill this gap, 94 healthy individuals participated in one of two contextual fear‐conditioning paradigms. In both paradigms, a differential fear‐learning phase was conducted, followed by a test phase in which the conditioned stimuli were presented in front of either conditioned or inherently aversive contextual images compared to neutral contexts. To capture defensive responses, we recorded subjective (threat and expectancy ratings) and physiological (electrodermal and cardiovascular) activity to the conditioned stimuli as a function of contextual threat. Besides indices of successful fear conditioning, our results revealed stronger threat and unconditioned stimulus expectancy ratings, cardiac deceleration, and skin conductance responses for threat and safety cues presented in inherently aversive compared to neutral contexts. Conditioned contexts had less impact on physiological responses to threat and safety cues than inherently aversive contexts. These findings provide new insights into the additive nature of defensive responses to fear cues and situations of contextual threat. Recent research challenges the idea that defensive states induced by potential and acute threat are mutually exclusive. In this study, we observed enhanced defensive responses to acute threat stimuli during aversive contexts as indexed by heart rate and skin conductance responses, indicating an interplay between potential and acute threat states that is influenced by contextual threat levels. [ABSTRACT FROM AUTHOR]

This Committee Report provides methodological, interpretive, and reporting guidance for researchers who use measures of heart rate (HR) and heart rate variability (HRV) in psychophysiological research. We provide brief summaries of best practices in measuring HR and HRV via electrocardiographic and photoplethysmographic signals in laboratory, field (ambulatory), and brain‐imaging contexts to address research questions incorporating measures of HR and HRV. The Report emphasizes evidence for the strengths and weaknesses of different recording and derivation methods for measures of HR and HRV. Along with this guidance, the Report reviews what is known about the origin of the heartbeat and its neural control, including factors that produce and influence HRV metrics. The Report concludes with checklists to guide authors in study design and analysis considerations, as well as guidance on the reporting of key methodological details and characteristics of the samples under study. It is expected that rigorous and transparent recording and reporting of HR and HRV measures will strengthen inferences across the many applications of these metrics in psychophysiology. The prior Committee Reports on HR and HRV are several decades old. Since their appearance, technologies for human cardiac and vascular monitoring in laboratory and daily life (i.e., ambulatory) contexts have greatly expanded. This Committee Report was prepared for the Society for Psychophysiological Research to provide updated methodological and interpretive guidance, as well as to summarize best practices for reporting HR and HRV studies in humans. [ABSTRACT FROM AUTHOR]

Heart rate variability (HRV) is an early marker of risk for various health conditions, and its analysis serves as a valuable tool for assessing older adults. This study aimed to describe the reference values of HRV parameters in older adults through a systematic review of the literature. The review included searches in MEDLINE (via PubMed®), EMBASE, Latin American and Caribbean Health Literature, Scopus, and Web of Science (WOS). Studies presenting reference values for at least one HRV linear analysis measure in older adults were considered eligible. Out of 1618 studies identified, only 11 met the inclusion criteria. Sample sizes of older adults ranged from 21 to 6250 subjects. The HRV measures assessed (mean RR intervals, SDNN, RMSSD, PNN50, LF, HF, and LF/HF ratio) varied significantly between studies, with no standardized methods for HRV analysis. We concluded that reference values for HRV measures in older adults vary widely between studies. The scientific literature on HRV reference values in older adults is still limited, and future studies should standardize assessment methods for HRV measures in this population. [ABSTRACT FROM AUTHOR]

Dysregulation of the autonomic nervous system (ANS) is commonly observed in various mental disorders, particularly when individuals engage in prolonged cognitive‐emotional tasks that require ANS adjustment to workload. Although the understanding of the temporal dynamics of sympathetic and parasympathetic tones in obsessive‐compulsive disorder (OCD) is limited, analyzing ANS reactions to cognitive‐emotional workload could provide valuable insights into one of the underlying causes of OCD. This study investigated the temporal dynamics of heart rate (HR) and pupil area (PA) while participants with OCD and healthy volunteers solved antisaccade tasks, with affective pictures serving as central fixation stimuli. The data of 31 individuals with OCD and 30 healthy volunteers were included in the study, comprising three separate blocks, each lasting approximately 8 min. The results revealed an increase in sympathetic tone in the OCD group, with the most noticeable rise occurring during the middle part of each block, particularly during the presentation of negative stimuli. Healthy volunteers demonstrated adaptive temporal dynamics of HR and PA from the first block to the last block of tasks, whereas individuals with OCD exhibited fewer changes over time, suggesting a reduced adaptation of the ANS sympathetic tone to cognitive‐emotional workload in OCD. Altered autonomic nervous system responses in patients with OCD could potentially underlie the causes of obsessive‐compulsive disorder; however, they have not been sufficiently investigated at present. By examining the temporal dynamics of pupil area and heart rate, we gain deeper insights into how individuals with obsessive‐compulsive disorder react to cognitive‐emotional stimuli. [ABSTRACT FROM AUTHOR]

Imagery has been associated with cardiovascular and psychological responses to stress; however, the mechanisms underlying this association are not fully understood. The present study examined if the ability to image mastering challenging or difficult situations moderated the relationship between heart rate reactivity and perceptions of stress and physiological arousal experienced during acute stress. Four hundred and fifty‐eight participants completed a standardized laboratory stress protocol with heart rate being measured throughout. After completing an acute psychological stress task, participants rated how stressed and physiologically aroused they felt (i.e., intensity) and whether they perceived the stress and physiological arousal as being helpful/unhelpful to performance (i.e., interpretation). Mastery imagery ability was assessed by questionnaire. Moderation analyses controlling for gender demonstrated that imagery ability moderated the relationship between heart rate reactivity and interpretation of stress (β = 0.015, p =.003) and perceived physiological arousal (β = 0.013, p =.004). Simple slope analysis indicated that in those with higher imagery ability, heart rate reactivity was associated with stress and arousal being perceived as more positive toward performance. Imagery ability did not moderate the relationship between heart rate reactivity and perceived stress intensity or physiological arousal intensity (p's >.05), but imagery ability did predict lower perceived stress intensity (β = −0.217, p <.001) and perceived physiological arousal intensity (β = −0.172, p <.001). Higher mastery imagery ability may possibly help individuals perceive responses to stress as more beneficial for performance and thus be an effective coping technique. While previous research has shown imagery being associated with cardiovascular and psychological responses to stress, the mechanisms underlying this association are not fully understood. By evidencing that imagery ability moderates the relationship between heart rate reactivity and interpretation of stress and perceived physiological arousal, we demonstrate a mechanism through which higher mastery imagery ability could help individuals perceive responses to stress as more beneficial for performance. [ABSTRACT FROM AUTHOR]

A rapid detection and processing of relevant information in our environment is crucial for survival. The human eyes are drawn to social or threatening stimuli as they may carry essential information on how to behave appropriately in a given context. Recent studies further showed a centralization of gaze that reminded of freezing behaviors in rodents. Probably constituting a component of an adaptive defense mode, centralized eye movements predicted the speed of motor actions. Here we conducted two experiments to examine if and how these presumably survival‐relevant gaze patterns interact. Subjects viewed images including social, that is, faces (Experiment 1, N = 50) or threatening stimuli, that is, snakes or spiders (Experiment 2, N = 50) while awaiting an inevitable (shock), no (safety), or an avoidable shock (flight) they could escape from by a fast button press. The social and threatening cues within the scenes differed in their distance from the image center and we acquired eye‐tracking and autonomic physiological data. Although we observed an initial orienting toward social and threatening stimulus aspects, this exploration pattern vanished towards the end of flight trials when a pronounced centralization of gaze emerged. Replicating previous findings, the amount of this center bias predicted the speed of motor reactions, and we observed a concurrent activation of the sympathetic and parasympathetic nervous system. Taken together, the exploration of potentially relevant cues seems to be part of a reflexive‐orienting response regardless of contextual valence. However, centralization of gaze may be a threat‐specific action‐preparatory response that occurs across a wide range of stimulus contexts. This study provides evidence for two sequential oculomotor effects indicating orienting and action preparation upon approaching threat. Relevant visual features such as social or threatening stimulus elements initially capture attention, but visual exploration sharply decreases as a function of action preparation under threat. This adaptive response is associated with a co‐activation of the sympathetic and parasympathetic autonomic system. [ABSTRACT FROM AUTHOR]

In healthy, young individuals, a reduction in cardiovascular output and a shift from sympathetic to parasympathetic (vagal) dominance is observed from wake into stages of nocturnal and daytime sleep. This cardiac autonomic profile, measured by heart rate variability (HRV), has been associated with significant benefits for cardiovascular health. Aging is associated with decreased nighttime sleep quality and lower parasympathetic activity during both sleep and resting. However, it is not known whether age-related dampening of HRV extends to daytime sleep, diminishing the cardiovascular benefits of naps in the elderly. Here, we investigated this question by comparing the autonomic activity profile between young and older healthy adults during a daytime nap and a similar period of wakefulness (quiet wake; QW). For each condition, from the electrocardiogram (ECG), we obtained beat-to-beat HRV intervals (RR), root mean square of successive differences between adjacent heart-beat-intervals (RMSSD), high-frequency (HF), low-frequency (LF) power, and total power (TP), HF normalized units (HFnu ), and the LF/HF ratio. As previously reported, young subjects showed a parasympathetic dominance during NREM, compared with REM, prenap rest, and WASO. Moreover, older, compared to younger, adults showed significantly lower vagally mediated HRV (measured by RMSSD, HF, HFnu ) during NREM. Interestingly, however, no age-related differences were detected during prenap rest or QW. Altogether, our findings suggest a sleep-specific reduction in parasympathetic modulation that is unique to NREM sleep in older adults.

The role of the heart in the experience of time has been long theorized but empirical evidence is scarce. Here, we examined the interaction between fine‐grained cardiac dynamics and the momentary experience of subsecond intervals. Participants performed a temporal bisection task for brief tones (80–188 ms) synchronized with the heart. We developed a cardiac Drift‐Diffusion Model (cDDM) that embedded contemporaneous heart rate dynamics into the temporal decision model. Results revealed the existence of temporal wrinkles—dilation or contraction of short intervals—in synchrony with cardiac dynamics. A lower prestimulus heart rate was associated with an initial bias in encoding the millisecond‐level stimulus duration as longer, consistent with facilitation of sensory intake. Concurrently, a higher prestimulus heart rate aided more consistent and faster temporal judgments through more efficient evidence accumulation. Additionally, a higher speed of poststimulus cardiac deceleration, a bodily marker of attention, was associated with a greater accumulation of sensory temporal evidence in the cDDM. These findings suggest a unique role of cardiac dynamics in the momentary experience of time. Our cDDM framework opens a new methodological avenue for investigating the role of the heart in time perception and perceptual judgment. With the novel consideration of cardiac dynamics in the Drift‐Diffusion Model of temporal decision making, we found a close relationship between heart rate and the perception of millisecond durations. Heart rate before a brief stimulus and the subsequent cardiac orienting response explained components of the perceptual evidence accumulation process to determine the stimulus duration. These findings suggest a unique role for bioenergetics in subsecond time perception. [ABSTRACT FROM AUTHOR]

Physical stress has been found to enhance arousability by visual sexual stimuli on a short‐term basis, as reflected in higher phasic pupil dilation responses, probably mediated by sympathetic nervous system (SNS)‐related processes. However, previous research has not addressed the specificity of this effect in terms of emotional valence, that is, whether it reflects an instance of general excitation transfer or a more specific mechanism. Thus, to further investigate changes in sexual processing after acute stress exposure, 40 male participants underwent either a predominantly sympathetic stressor (3 min sustained handgrip) or similar control procedure. After stress induction, pictures varying in valence as well as sexual versus non‐sexual arousal were presented (for 5000 ms each). Using principal component analysis, pupillary responses during picture viewing were dissociated into fast and slow components (early vs. late response phases). In addition, startle eyeblink responses were elicited by bursts of white noise (50 ms, 105 dB) in half of the trials and recorded at the orbicularis oculi via electromyography. Skin conductance and heart rate were co‐registered, as well. While affective startle modulation and skin conductance responses to emotional stimuli were unaffected by previous stress exposure, both evoked heart‐rate deceleration (but not acceleration) and pupil responses were specifically enhanced with sexually arousing stimuli in stressed participants, and this effect was mediated by blood pressure reactivity as an index of preceding SNS activation. Taken together, our findings provide strong evidence for enhancement of sexual processing by acute stress exposure in men and suggest differential involvement of parasympathetic versus sympathetic mechanisms. Abstract While long‐term stress exposure has been linked to impaired sexual function, animal models of effects of acute stress on sexual arousability have yielded heterogeneous results, and human research is scarce. The present study replicates and extends evidence for increased physiological responsivity to erotic cues after sympathetic nervous system activation (in men), revealing differential involvement of parasympathetic versus sympathetic mechanisms. [ABSTRACT FROM AUTHOR]

Mirth is elicited by the perception of humor, which requires the resolution of an incongruity in an unexpected and playful manner. Previous psychophysiological research using affective pictures is scarce, and did not elucidate the cognitive and affective components of the humor process. In this study, the passive viewing paradigm is applied to mirthful, incongruent, neutral and erotic pictures to characterize the emotional response of mirth. Physiological (zygomaticus major [ZM] activity, skin conductance response [SCR] and heart rate [HR]), behavioral (free viewing time) and subjective responses (mirthful ratings) were recorded from 63 participants. The presence of an inflection change in the ZM response and mirthfulness ratings were used as markers of humor comprehension. Participants showed the greatest ZM and HR in response to mirthful compared to incongruent, erotic and neutral pictures, as well as a stronger SCR response to mirthful compared to incongruent and neutral pictures. The overall results shed light on the temporal course of the humor process, suggesting that humor comprehension (cognitive component) occurred around 1000–1500 ms after picture onset, according to the ZM and SCR responses; and the humor appreciation stage (emotional component) occurred at around 3500 ms after stimulus onset, according to the HR and SCR changes. Moreover, marked interindividual variability was observed in the number of smiles, and in the pictures that provoked them. This points to the complexity of the humor process, and suggests the need to develop methods to elicit mirth and elucidate the factors potentially underlying individual differences in humor. To characterize the emotional response of mirth, the passive viewing paradigm is applied to mirthful, incongruent, neutral and erotic pictures while recording physiological, behavioral and subjective responses. Our results showed increased zygomatic, heart rate and skin conductance responses to mirthful pictures. The latencies of these responses provide insight into the temporal course of the cognitive and emotional components of the humor process. [ABSTRACT FROM AUTHOR]

A central tenet of many theories of emotion is that emotional states are accompanied by distinct patterns of autonomic activity. However, experimental studies of coherence between subjective and autonomic responses during emotional states provide little evidence of coherence. Crucially, previous studies investigating coherence have either adopted univariate approaches or made limited use of multivariate analytic approaches by investigating subjective and autonomic responses separately. The current study addressed this question using a multivariate dimensional approach to build a common autonomic‐subjective affective space incorporating subjective responses and three different autonomic signals (heart rate, skin conductance response, and pupil diameter), measured during an emotion‐inducing task, in 51 participants. Results showed that autonomic and subjective responses could be adequately described in a two‐dimensional affective space. The first dimension included contributions from subjective and autonomic responses, indicating coherence, while contributions to the second dimension were almost exclusively of autonomic covariance. Thus, while there was a degree of coherence between autonomic and subjective emotional responses, there was substantial structure in autonomic responses that did not covary with subjective emotional experience. This study, therefore, contributes new insights into the relationship between subjective and autonomic emotional responses, and provides a framework for future multimodal emotion research, enabling both hypothesis‐ and data‐driven testing. Whether our subjective emotions are accompanied by distinct physiological states is hotly debated. Using a novel multivariate analysis enabling physiological data and subjective experience to be analysed within the same dimensional structure, we find evidence for both coherence between physiological markers of autonomic state and subjective experience, and evidence for a substantial degree of divergence. [ABSTRACT FROM AUTHOR]

The degree to which experimenters shape participant behavior has long been of interest in experimental social science research. Here, we extend this question to the domain of peripheral psychophysiology, where experimenters often have direct, physical contact with participants, yet researchers do not consistently test for their influence. We describe analytic tools for examining experimenter effects in peripheral physiology. Using these tools, we investigate nine data sets totaling 1,341 participants and 160 experimenters across different roles (e.g., lead research assistants, evaluators, confederates) to demonstrate how researchers can test for experimenter effects in participant autonomic nervous system activity during baseline recordings and reactivity to study tasks. Our results showed (a) little to no significant variance in participants' physiological reactivity due to their experimenters, and (b) little to no evidence that three characteristics of experimenters that are well known to shape interpersonal interactions-status (using five studies with 682 total participants), gender (using two studies with 359 total participants), and race (in two studies with 554 total participants)-influenced participants' physiology. We highlight several reasons that experimenter effects in physiological data are still cause for concern, including the fact that experimenters in these studies were already restricted on a number of characteristics (e.g., age, education). We present recommendations for examining and reducing experimenter effects in physiological data and discuss implications for replication.

The relationship between adiposity and cardiovascular disease morbidity and mortality is complex. One pathway through which adiposity may influence future health outcomes is by altering how biological systems respond to stress. The current study aimed to examine the association between two metrics of adiposity (body mass index and waist‐hip ratio) and two indices of cardiovascular stress responses (reactivity and habituation). A sample of 455 participants (Mean age = 19.47, SD = 1.25 years; BMI = 24.32, SD = 5.04 kg/m2; 62% female; 17.9% Hispanic/Latino; 65.2% White, 18.7% Asian, 7.9% Black, 0.2% American Indian/Alaska Native, and 7% other) completed two acute psychosocial stress tasks. Heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded throughout each stressor. In unadjusted and adjusted models, there were no statistically significant associations between adiposity and HR, SBP, or DBP stress reactivity or habituation. The current data do not support the hypothesis that adiposity influences health by altering cardiovascular responses to acute psychological stress. Results are at odds with prior population‐level studies and the single prior study examining adiposity and habituation. At the same time, results are in line with mounting evidence that adiposity itself does not drive poor cardiovascular outcomes seen in people classified as overweight or obese. In a sample of young adults, we found no evidence that adiposity was related to cardiovascular stress reactivity or cardiovascular habituation to repeated stress exposure. Our research adds to a growing body of literature suggesting adiposity in itself is not a risk factor for poor cardiovascular outcomes. [ABSTRACT FROM AUTHOR]

Fear and anxiety are crucial for adaptive responding in life‐threatening situations. Whereas fear is a phasic response to an acute threat accompanied by selective attention, anxiety is characterized by a sustained feeling of apprehension and hypervigilance during situations of potential threat. In the current literature, fear and anxiety are usually considered mutually exclusive, with partially separated neural underpinnings. However, there is accumulating evidence that challenges this distinction between fear and anxiety, and simultaneous activation of fear and anxiety networks has been reported. Therefore, the current study experimentally tested potential interactions between fear and anxiety. Fifty‐two healthy participants completed a differential fear conditioning paradigm followed by a test phase in which the conditioned stimuli were presented in front of threatening or neutral contextual images. To capture defense system activation, we recorded subjective (threat, US‐expectancy), physiological (skin conductance, heart rate) and visuocortical (steady‐state visual evoked potentials) responses to the conditioned stimuli as a function of contextual threat. Results demonstrated successful fear conditioning in all measures. In addition, threat and US‐expectancy ratings, cardiac deceleration, and visuocortical activity were enhanced for fear cues presented in threatening compared with neutral contexts. These results are in line with an additive or interactive rather than an exclusive model of fear and anxiety, indicating facilitated defensive behavior to imminent danger in situations of potential threat. Our research adds a new perspective on a potential interaction between fear and anxiety. We provide first evidence for enhanced defensive (fear) responses in potentially threatening (anxiety) contexts as indexed by multiple measures of defensive responding (perceived threat, HR, and EEG), suggesting that anxiety may facilitate fear responses rather than both emotional states being mutually exclusive. [ABSTRACT FROM AUTHOR]

Anxiety and balance and postural control are linked via common neural pathways, such as the parabrachial nucleus network. A laboratory‐based model of general anxiety disorder (GAD) using the CO2 challenge, has potential to be used to observe this relationship, potentially mimicking subjective, autonomic, and neuropsychological features of GAD. The current feasibility study used the CO2 challenge to explore postural control changes in healthy adults. It was predicted that during the CO2 condition, participants would show increased postural sway path length and decreased sway stability, compared with a normal air breathing condition. To assess this, heart and breathing rate, quiet standing postural sway path length, sway dynamic stability, and subjective measures of emotion were measured either before and after or during and after the inhalation conditions. Results demonstrated that CO2 inhalation led to both an increase in sway path length and reduced sway stability compared to the air breathing conditions; the effect on sway path lasted after the inhalation of CO2 had ceased. Additionally, replication of HR and subjective measures of emotion were observed when comparing air and CO2 conditions. This provides experimental evidence that CO2 inhalation can affect balance, suggestive of shared mechanisms between anxiety and balance performance, as well as indicating that the CO2 model of GAD is suitable to look at changes in balance performance in healthy adults. Future use of this model to explore factors that can reduce the influence of GAD on balance would be beneficial as would a more detailed exploration of the neural pathways associated with the associated comorbidity. This feasibility study demonstrates the potential of using the CO2 challenge model as an experimental tool to better understand the relationship between anxiety and balance disorders. We evidenced increased path sway and stability as the result of 7.5% CO2 inhalation induced anxiety state. Furthermore, increased heart rate and poorer self‐reported mood state due to the CO2 inhalation, corroborate previous findings of generalised anxiety disorder symptomology in this model. [ABSTRACT FROM AUTHOR]

Classical views suggest that experienced affect is related to a specific bodily response, whereas recent perspectives challenge this view postulating that similar affective experiences rather evoke different physiological responses. To further advance this debate in the field, we used representational similarity analysis to investigate the correspondence between subjective affect (arousal and valence ratings) and physiological reactions (skin conductance response [SCR], startle blink response, heart rate, and corrugator activity) across various emotion induction contexts (picture viewing task, sound listening task, and imagery task). Significant similarities were exclusively observed between SCR and arousal in the picture viewing task. However, none of the other physiological measures showed a significant relation with valence and arousal ratings in any of the tasks. These findings are discussed within the framework of the Populations hypothesis, suggesting that physiological responses do not depend on the experienced affect but are directly associated with the context in which they are evoked. We used representational similarity analysis to provide new insights into the relationship between subjective affect and physiological reactivity across three affect‐inducing tasks. Similarities between representational patterns of subjective affect and physiological reactivity only emerged for one physiological variable (SCR and arousal) in a specific context (i.e., passive picture viewing task). Our findings inform the ongoing debate on the relationship between physiological changes and the valence and arousal properties of affect. [ABSTRACT FROM AUTHOR]

A common belief is that narcissism is a manifestation of high self‐esteem. Here, we argue that self‐esteem and narcissism are fundamentally distinct and have unique early physiological indicators. We hypothesized that children predisposed to narcissism would show elevated, whereas children predisposed to high self‐esteem would show lowered, physiological arousal in social‐evaluative contexts. We tested this in a prospective study including 113 children, who were first assessed at age 4.5, a critical age when children begin evaluating themselves through others' eyes. At age 4.5, children sang a song in front of an audience while being videotaped. Children's physiological arousal (skin conductance, heart rate, and heart rate variability) was assessed while children anticipated, performed, and recovered from the singing task. At age 7.5, children's narcissism and self‐esteem levels were assessed. Consistent with our predictions, children predisposed to higher narcissism levels showed elevated skin conductance levels during anticipation. Their skin conductance levels further rose during performance (but less so than for other children) and failed to return to baseline during recovery. By contrast, children predisposed to higher self‐esteem levels showed lowered skin conductance levels throughout the procedure. The effects emerged for skin conductance but not heart rate or heart rate variability, suggesting that arousal was sympathetically driven. Effects were larger and more robust for self‐esteem than for narcissism. Together, these findings uncover distinct physiological indicators of narcissism and self‐esteem: Narcissism is predicted by indicators reflecting early social‐evaluative concerns, whereas self‐esteem is predicted by indicators reflecting an early sense of comfort in social‐evaluative contexts. Some experts fear that self‐esteem can develop into narcissism. Challenging this view, we show that self‐esteem and narcissism (at age 7.5) have distinct early physiological indicators (at age 4.5). In our prospective study, narcissism was predicted by elevated, whereas self‐esteem was predicted by lowered, physiological arousal in a social‐evaluative context. [ABSTRACT FROM AUTHOR]

In response to the COVID‐19 pandemic, prior studies have modified the Trier Social Stress Test to be conducted remotely. The current study aimed to extend these studies to test whether a remote Trier Social Stress Test (rTSST) can elicit (a) affective, (b) blood pressure, and (c) heart rate responses relative to a control condition and whether these responses were reliable when assessed 1 week later. Participants (N = 99, 19.7 ± 3.5 years, 55% female) were randomized to a control or stress condition. Participants received blood pressure monitors in person. Controls completed easier versions of the tasks with a single, friendly researcher. Stress participants performed more difficult versions of the task in front of two judges who participants believed were rating their performance. Blood pressure and heart rate were measured every 2 min throughout, while affect was assessed at baseline, after the final task, and following recovery. The rTSST was feasible to administer with minimal technical issues reported. Participants reported lower positive affect and higher negative affect during the tasks in the stress condition relative to controls. Similarly, stress participants had higher cardiovascular responses during the tasks relative to controls, except that blood pressure was not elevated during mental arithmetic in stress participants relative to controls. Cardiovascular responses demonstrated good test–retest reliability when assessed 1 week later, especially when computed using area under the curve methods. Overall, a rTSST can be used to elicit affective and cardiovascular reactivity and provides an opportunity to increase the accessibility of research participation among diverse populations. We demonstrate that the Trier Social Stress Test can evoke both affective and cardiovascular (heart rate and blood pressure) responses when delivered online and remotely. This protocol can be administered during the COVID‐19 pandemic and could be used to include underserved and other populations that may have less accessibility to participate in research protocols. [ABSTRACT FROM AUTHOR]

Using heart rate (HR) measurements to detect mental stress in naturalistic settings is hampered by the physiological impact of hemodynamic and metabolic demands. Correcting HR for these demands can help isolate fluctuations in HR associated with psychosocial stress responses, a concept termed additional heart rate (aHR). This study examined whether adding predictors for posture, activity type, and lagged movement intensity for the prolonged impact of physical activity (PA) improved aHR estimation across various manipulations of mental stress, posture, and PA in a controlled laboratory environment (n = 197). Accelerometer signals were used to obtain the movement intensity and to classify posture and activity type. Posture, activity type, and lagged movement intensity each led to a significant improvement in HR estimation, as measured by adjusted R 2 and root mean squared error. However, HR was overestimated during quiet sitting. The aHR, computed as the difference between observed and predicted HR, generally underestimated observed task-baseline reactivity but was sensitive to individual differences in reactivity to mental stressors. Between-subject correlations of aHR with task-baseline reactivity ranged from 0.62 to 0.93 across conditions. On a within-subject level, the ability of aHR to differentiate between exposure to physical stress and mental stress was limited (recall = 0.32, precision = 0.31), but better than that of observed HR (recall = 0.02, precision = 0.02). Future research should explore the potential of this novel aHR estimation method in differentiating physical and mental demands on HR in daily life, and its predictive value for health outcomes., (© 2024 The Author(s). Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Both greater cardiovascular reactivity and lesser reactivity ("blunting") to laboratory stressors are linked to poor health outcomes, including among people who have a history of traumatic experiences. In a sample of recently separated and divorced adults (N = 96), this study examined whether differences in cardiovascular reactivity might be explained by differences in the personal emotional salience of the tasks and trauma history. Participants were assessed for trauma history, current distress related to their marital dissolution, and cardiovascular reactivity during two tasks, a serial subtraction math stressor task and a divorce‐recall task. Participants with a greater trauma history evidenced less blood pressure reactivity to the serial subtraction task (a low personal emotional salience task) when compared to participants with less trauma history. In contrast, participants with a greater trauma history evidenced higher blood pressure reactivity to the divorce‐recall task, but only if they also reported more divorce‐related distress (high personal emotional salience). These associations were not significant for heart rate reactivity. Among people with a history of more traumatic experiences, a task with low personal salience was associated with a lower blood pressure response, whereas a task with higher personal emotional salience was associated with a higher blood pressure response. Future studies examining cardiovascular reactivity would benefit from determining the personal emotional salience of tasks, particularly for groups that have experienced stressful life events or trauma. We aimed to reconcile apparent discrepancies between traditional and blunting models of cardiovascular reactivity by accounting for the emotional salience of laboratory tasks. In this study, people who had experienced more trauma showed blunted reactivity to a serial subtraction task, but greater reactivity to a divorce‐recall task if they had higher distress related to their divorce, suggesting that the emotional content of tasks might help to explain seemingly discrepant prior empirical findings. [ABSTRACT FROM AUTHOR]

In this study, brain imaging data from functional near‐infrared spectroscopy (fNIRS) associated with skin conductance response (SCR), heart rate (HR), and reaction time (RT) were combined to determine if the combination of these indicators could improve the efficiency of deception detection in concealed information test (CIT). During the CIT, participants were presented with a series of names and cities that served as target, probe, or irrelevant stimuli. In the guilty group, the probe stimuli were the participants' own names and hometown cities, and they were asked to deny this information. Our results revealed that probe items were associated with longer RT, larger SCR, slower HR, and higher oxyhemoglobin (HbO) concentration changes in the inferior prefrontal gyrus (IFG), middle frontal gyrus (MFG), and the superior frontal gyrus (SFG) compared with irrelevant items for participants in the guilty group but not in the innocent group. Furthermore, our results suggested that the combination of RT, SCR, HR, and fNIRS indicators could improve the deception detection efficiency to a very high area under the ROC curve (0.94) compared with any of the single indicators (0.74–0.89). The improved deception detection efficiency might be attributed to the reduction of random error and the diversiform underlying the psychophysiological mechanisms reflected by each indicator. These findings demonstrate a feasible way to improve the deception detection efficiency by using combined multiple indicators. The current study demonstrates the use of multiple indicators as a feasible method to improve the detection of deception with a high detection efficiency (0.94). This is the first study to combine brain imaging data from fNIRS with SCR, HR and RT to detect deception in a concealed information test. [ABSTRACT FROM AUTHOR]

Most pain studies have focused on only two aspects of pain: the influence of pain on attentional processing and the modulation of pain perception by affective stimuli. However, the influence of tonic pain on the attentional processing of affective stimuli has not been studied. In this study, we investigated the effects of tonic pain on the attentional processing of affective stimuli, focusing on autonomic responses and their relationship with both EEG power and functional connectivity. Forty participants (20 men and 20 women) received tonically painful and nonpainful thermal stimulation while viewing blocks of pleasant, unpleasant, or neutral images. The galvanic skin conductance response (SCR), electrocardiographic activity, and electroencephalographic (EEG) activity in the delta and theta bands were recorded. Participants rated the unpleasantness of the pain at the end of each block. Typical affective SCR and heart rate (HR) patterns were found in the no‐pain condition, but when the pain was delivered, these patterns disappeared. EEG power and functional connectivity results showed that tonic pain affected the delta band in the central region during pleasant and unpleasant image blocks. Our findings suggest that tonic pain captured attentional focus and reduced the cognitive resources available for processing affective stimuli, altering the emotional experience associated with pain. Previous studies with pain patients suggest that pain reduces the attentional processing of affective stimuli. However, these results could be a consequence of affective disorders related to pain diseases. The current article provides new subjective and physiological evidence that tonic pain reduces the attentional processing of affective stimuli in healthy participants. [ABSTRACT FROM AUTHOR]

Humans and many animals devalue future rewards as a function of time (temporal discounting). Increased discounting has been linked to various psychiatric conditions, including substance‐use‐disorders, behavioral addictions, and obesity. Despite its high intra‐individual stability, temporal discounting is partly under contextual control. One prominent manipulation that has been linked to increases in discounting is the exposure to highly arousing appetitive cues. However, results from trial‐wise cue exposure studies appear highly mixed, and changes in physiological arousal were not adequately controlled. Here we tested the effects of appetitive (erotic), aversive, and neutral visual cues on temporal discounting in 35 healthy male participants. The contribution of single‐trial physiological arousal was assessed using comprehensive monitoring of autonomic activity (pupil size, heart rate, electrodermal activity). Physiological arousal was elevated following aversive and in particular erotic cues. In contrast to our pre‐registered hypothesis, steepness of temporal discounting was not significantly affected by emotional cues of either valence. Aversive cues tended to increase decision noise. Computational modeling revealed that trial‐wise arousal only accounted for minor variance over and above aversive and erotic condition effects, arguing against a general effect of physiological arousal on temporal discounting. [ABSTRACT FROM AUTHOR]

Social support is a major contributor to the link between social ties and beneficial health outcomes. Research to date has focused on how receiving support from others might be good for us; however, we know less about the health effects of giving support to others. Based on prior work in animals showing that stimulating neural circuitry important for caregiving behavior can reduce sympathetic-related responses to stressors, it is possible that, in humans, giving to others can reduce stressor-evoked sympathetic nervous system responding, which has implications for health outcomes. To test the effect of giving support on the physiological stress response, participants either wrote a supportive note to a friend (support-giving condition) or wrote about their route to school/work (control condition) before undergoing a standard laboratory-based stress task. Physiological responses (heart rate, blood pressure, salivary alpha-amylase, salivary cortisol), and self-reported stress were collected throughout the protocol. In line with hypotheses, support giving (vs. control) reduced sympathetic-related responses (systolic blood pressure and alpha-amylase) to the stressor. No effects of support giving were found on self-reported psychological stress or cortisol levels. Results add to existing knowledge of the pathways by which support giving may lead to health benefits and highlight the contribution of giving to others in the broader social support-health link.

In healthy individuals, a reduction in cardiovascular output and a shift to parasympathetic/vagal dominant activity is observed across nocturnal sleep. This cardiac autonomic profile, often measured by heart rate variability (HRV), has been associated with significant benefits for the cardiovascular system. However, little is known about the autonomic profile during daytime sleep. Here, we investigated the autonomic profile and short-term reliability of HRV during daytime naps in 66 healthy young adults. Participants took an 80-120 min polysomnographically recorded nap at 1:30 pm. Beat-by-beat RR interval values (RR), high (HF) and low frequency (LF) power, total power (TP), HF normalized units (HF(nu)), and the LF/HF ratio were obtained for 5 min during presleep wakefulness and during nap sleep stages (N2, N3, REM). A subsample of 37 participants took two additional naps with 2 weeks between recordings. We observed lengthening of the RR, higher HF and HF(nu), and lower LF/HF during NREM, compared with REM and wake, and a marked reduction of LF and TP during N3. Intraclass correlation coefficients highlighted a short-term stability of RR and HF ranging across sleep stages between 0.52-0.76 and 0.52-0.80, respectively. Our results suggest that daytime napping in healthy young adults is associated with dynamic changes in the autonomic profile, similar to those seen during nocturnal sleep. Moreover, a reliable intraindividual measure of autonomic cardiac activity can be obtained by just a single daytime nap depending on specific parameters and recording purposes. Nap methodology may be a new and promising tool to explore sleep-dependent, autonomic fluctuations in healthy and at-risk populations.

Reduced heart rate variability (HRV) is proposed to mediate the relation between depressive symptoms and cardiovascular health problems. Yet, several studies have found that in women depression is associated with higher HRV levels, whereas in men depression is associated with lower HRV levels. So far, these studies have only examined gender differences in HRV levels using a single assessment. This study aimed to test the interactive effects of gender and sadness on ambulatory-assessed HRV levels. A sample of 60 (41 women) employees participated in an ambulatory study. HRV levels (mean of successive differences; MSD) were continuously measured for 24 h. During the daytime, hourly assessments of sadness and other mood states were taken, while depressive symptoms were assessed with the Center for Epidemiologic Studies Depression scale (CES-D). Gender differences were observed when examining the impact of average daily sadness on MSD. In women, but not in men, the total amount of sadness experienced during the day was associated with higher circadian MSD levels. These findings suggest that researchers need to take gender differences into account when examining the relation between sadness, HRV, and cardiovascular problems.

Cannabis is the most commonly used psychotropic drug in the United States, after alcohol. Despite its apparent sedative and calming effects, cannabis and its main psychoactive constituent, ∆9‐tetrahydrocannabinol (THC) can produce serious adverse effects including tachycardia and anxiety. These effects can be especially pronounced in women, who remain underrepresented in clinical cannabinoid research. The present study is one of the first to characterize the effects of single doses of oral THC on autonomic nervous system function in healthy adult women. Occasional female cannabis users participated in three laboratory sessions in which they received oral THC (7.5 and 15 mg) and placebo. Autonomic measures included heart rate (HR), blood pressure (BP), pre‐ejection period (PEP) a measure of cardiac sympathetic functioning, and high frequency heart rate variability (HF‐HRV) a measure of parasympathetic cardiac control. Autonomic responses were examined in relation to subjective drug effects. THC dose‐dependently increased HR, decreased HF‐HRV, and increased ratings of feeling a drug effect, cannabis‐like intoxication, and anxiety. Although the drug did not significantly affect BP or PEP, HR was negatively related to both PEP and HF‐HRV. HF‐HRV, the measure of parasympathetic activity, was significantly negatively related to subjective measures of cannabis intoxication (but not anxiety) at the 15 mg dose only. PEP was not significantly related to any subjective measure. These results extend our knowledge of the autonomic effects of THC in relation to subjective drug experience. This and future studies will help us to understand risk factors related to cannabis use. Cannabis and its main psychoactive constituent, ∆9‐tetrahydrocannabinol (THC) can produce adverse effects including tachycardia and anxiety. These effects can be especially pronounced in women, who remain underrepresented in clinical cannabinoid research. The present study is one of the first to characterize the effects of single doses of oral THC on autonomic nervous system function in healthy adult women. The results extend our knowledge of the autonomic effects of THC in relation to subjective drug experience. [ABSTRACT FROM AUTHOR]

Concealed Information Tests (CIT) are administered to verify whether suspects recognize certain features from a crime. Whenever it is presumed that innocent suspects were contaminated with critical information (e.g., the perpetrator had a knife), the examiner may ask more detailed questions (e.g., specific types of knives) to prevent false positives. However, this may increase the number of false negatives if the true perpetrator fails to discern specific details from its plausible irrelevant controls, or because detailed crime‐scene information may be forgotten. We examined whether presenting items at the exemplar level protects against contamination, and whether it compromises the sensitivity in a physiological CIT. Participants (N = 142) planned a mock‐robbery, with critical items encoded either at the category or at the exemplar level. The CIT was administered immediately or after a 1‐week‐delay, with questions phrased at the categorical or exemplar level. There were no effects of time delay. Results revealed that when item detailedness was congruent at encoding and testing, the SCR, HR, and RLL showed larger differential responses, as compared with incongruent conditions. Participants contaminated with crime knowledge at the categorical level did not show a CIT‐effect for crime details at the exemplar level, suggesting detailed questions may counter the leakage problem. Asking questions at the exemplar level did not reduce the CIT detection efficiency as compared to asking questions at the categorical level. The importance of congruency between encoding and testing provides examiners with a challenge, as it is difficult to estimate how details are naturally encoded. The Concealed Information Test (CIT) depends on the assumption that only guilty suspects have crime knowledge. As this assumption cannot always be met in real‐life, examiners may probe for more detailed information. We investigated whether use of detailed items affects accuracy in the CIT, and whether this depends on congruency between crime encoding and CIT testing. The current findings speak for the use of detailed questions. [ABSTRACT FROM AUTHOR]

Emotion regulation (ER) can be implemented by different strategies which differ in their capacity to alter emotional responding. What all strategies have in common is that cognitive control must be exercised in order to implement them. The aim of the present preregistered study was to investigate whether the two ER strategies, expressive suppression and distancing, require different amounts of cognitive effort and whether effort is associated with personality traits. Effort was assessed subjectively via ratings and objectively via pupillometry and heart period. In two studies, N = 110 and N = 52 healthy adults conducted an ER paradigm. Participants used suppression and distancing during inspection of positive and negative pictures. They also had the choice to reapply either of the strategies at the end of the paradigm. Although distancing was more effective in downregulation of subjective arousal (Study 1: p <.001,ηp2 =.20; Study 2: p <.001, ηp2 =.207), about two thirds reapplied suppression, because it was perceived as less effortful. Effort was rated significantly lower for suppression compared to distancing (Study 1: p =.042, ηp2 =.04; Study 2: p =.002, ηp2 =.13). However, differences in effort were not reflected in pupillary data or heart period. Broad and narrow personality traits were neither associated with the preferred strategy nor with subjective or physiological effort measures. Findings suggest that people tend to use the ER strategy that is perceived as less effortful, even though it might not be the most effective strategy. Our research on subjective and physiological effort of two emotion regulation strategies adds a new perspective on emotion regulation choice. We provide evidence that the choice of which emotion regulation strategy to apply is not primarily based on its effectiveness, but on the perceived cognitive effort. This may have negative consequences for individuals when the least effortful strategy is not the most effective one. [ABSTRACT FROM AUTHOR]

Well‐powered studies on the physiological concomitants underlying affect and its regulation during emerging adulthood are warranted to provide novel insight into mental health. The association between autonomic nervous system activity and emotional states occurring under natural conditions in daily life was investigated in individuals (N = 549, age 14–21, females 45.6%) without any lifetime mental disorder from an epidemiological cohort study in Germany. Using ecological momentary assessment, mood and optimism/pessimism were assessed over 4 days simultaneously with continuous heart rate monitoring. Lower vagal activity was found in mood states accompanied by high arousal (wakefulness, mania) and greater vagal activity in mood states with low arousal (calmness, pessimism). Findings illustrate important associations between autonomic nervous system activity and mood in youth under ecologically valid conditions. Vagal activity presents a prominent pathway by which mood may influence physiological function or vice versa. In contrast to commonly performed laboratory assessments, the ambulatory assessment in participants' daily life allows an application of the results to the field. This study elucidates to what degree mood and optimism/pessimism in the daily life of adolescents and young adults without mental disorders are associated with vagal‐mediated heart rate variability, thus contributing insights into the potential pathways between autonomic nervous system activity and mood as a function of arousal in youth under ecologically valid conditions. The ambulatory design of the current study increases the ecologic validity and generalizability of the found effects. [ABSTRACT FROM AUTHOR]

Wired ambulatory monitoring of the electrocardiogram (ECG) is an established method used by researchers and clinicians. Recently, a new generation of wireless, compact, and relatively inexpensive heart rate monitors have become available. However, before these monitors can be used in scientific research and clinical practice, their feasibility, validity, and reproducibility characteristics have to be investigated. Therefore, we tested how two wireless heart rate monitors (i.e., the Ithlete photoplethysmography (PPG) finger sensor and the Cortrium C3 ECG monitor perform against an established wired reference method (the VU‐AMS ambulatory ECG monitor). Monitors were tested on cross‐instrument and test‐retest reproducibility in a controlled laboratory setting, while feasibility was evaluated in protocolled ambulatory settings at home. We found that the Cortrium and the Ithlete monitors showed acceptable agreement with the VU‐AMS reference in laboratory setting. In ambulatory settings, assessments were feasible with both wireless devices although more valid data were obtained with the Cortrium than with the Ithlete. We conclude that both monitors have their merits under controlled laboratory settings where motion artefacts are minimized and stationarity of the ECG signal is optimized by design. These findings are promising for long‐term ambulatory ECG measurements, although more research is needed to test whether the wireless devices' feasibility, validity, and reproducibility characteristics also hold in unprotocolled daily life settings with natural variations in posture and activities. The current study investigates whether two modern, wireless heartrate monitors offer similar reliability and validity characteristics as a standard ECG reference method under a controlled laboratory setting. Moreover, feasibility characteristics of the two wireless monitors were investigated in ambulatory settings in a highly controlled protocol. Results indicated that with both the Cortrium and the Ithlete HR(V) monitor data collection at home is feasible, although the Cortrium was able to deliver more valid data. [ABSTRACT FROM AUTHOR]

Depression and anxiety have been linked with reduced stress‐induced cardiovascular reactivity (CVR), which could be indicative of autonomic dysregulation. Less is known about the association between work‐related fatigue and CVR. Truck drivers experience high levels of depression, anxiety, and fatigue, with repeated psychophysiological stressors on the road, yet little is known about the effects of these conditions on their CVR. Three hundred eighty six truck drivers completed the Hospital Anxiety and Depression Scale (HADS) and the Occupational Fatigue Exhaustion/Recovery Scale (OFER‐15). Systolic (SBP) and diastolic (DBP) blood pressure and heart rate (HR) were measured at rest and during a stressor protocol to measure CVR. Multivariate regression analyses were used to determine relationships between variables and adjusted for nine key covariates. Higher symptoms of persistent fatigue were related to a reduced SBP reactivity (β = −.236, p =.009) and reduced DBP reactivity (β = −.257, p =.005), whereas there was a positive trend between acute fatigue and DBP reactivity (β =.169, p =.052). Higher symptoms of anxiety were related to a reduced SBP reactivity (β = −.164, p =.016). This study demonstrated in a population of truck drivers that both anxiety and persistent fatigue were related to an attenuated SBP reactivity in a combined model, whereas there was a positive trend between acute fatigue solely and DBP reactivity. These novel findings may have serious implications for cardiovascular disease risk in truck drivers, and future research should attempt to establish the causal effect of these associations and the underlying physiological mechanisms. Truck drivers experience high levels of depression, anxiety, and fatigue, as well as repeated psychophysiological stressors on the road. Our study is novel by showing that increased fatigue and symptoms of anxiety are related to attenuated cardiovascular reactivity in truck drivers. Attenuated physiological responses may have negative consequences for future health status of truck drivers. [ABSTRACT FROM AUTHOR]

Joint performance can lead to the synchronization of physiological processes among group members during a shared task. Recently, it has been shown that synchronization is indicative of subjective ratings of group processes and task performance. However, different methods have been used to quantify synchronization, and little is known about the effects of the choice of method and level of analysis (individuals, dyads, or triads) on the results. In this study, participants performed a decision‐making task in groups of three while physiological signals (heart rate and electrodermal activity), positive affective behavior, and personality traits were measured. First, we investigated the effects of different levels of analysis of physiological synchrony on affective behavior. We computed synchrony measures as (a) individual contributions to group synchrony, (b) the average dyadic synchrony within a group, and (c) group‐level synchrony. Second, we assessed the association between physiological synchrony and positive affective behavior. Third, we investigated the moderating effects of trait anxiety and social phobia on behavior. We discovered that the effects of physiological synchrony on positive affective behavior were particularly strong at the group level but nonsignificant at the individual and dyadic levels. Moreover, we found that heart rate and electrodermal synchronization showed opposite effects on group members' display of affective behavior. Finally, trait anxiety moderated the relationship between physiological synchrony and affective behavior, perhaps due to social uncertainty, while social phobia did not have a moderating effect. We discuss these results regarding the role of different physiological signals and task demands during joint action. Impact Statement Despite the inherent multilevel structure of groups, little is known regarding how physiological coupling between group members relates to their behaviors during joint group tasks at multiple levels (individual, dyadic, and group). We showed that the relationship between physiological synchrony and smiling/laughing behaviors made by group members were particularly strong at the group level but nonsignificant at the individual and dyadic levels. By using innovative quantification methods—Multidimensional Recurrence Quantification Analysis—we highlight the importance of modeling data in a way that allows for multilevel considerations within groups. [ABSTRACT FROM AUTHOR]

We examined the neural correlates of resting cardiac vagal activity in a sample of 432 participants (206 male; 61 African American; mean age 42 years). Pulsed arterial spin labeling was used to quantify whole brain and regional cerebral blood flow at rest. High-frequency heart rate variability (HF-HRV) was used to measure cardiac vagal activity at rest. The primary aim was to determine whether brain regions implicated in regulating cardiac vagal reactions were also related to cardiac vagal activity at rest, and whether these associations varied by sex or race. Brain areas previously related to vagal reactivity were related to resting HF-HRV. Directionality of relationships differed between overall and regional flows. Some relationships were only observed in women and African Americans. There appears to be communality between brain regions associated with task-induced vagal reactivity and those associated with resting cardiac vagal activity.

The neurovisceral integration hypothesis suggests in part that cerebral control of autonomic function conveys comparable control of executive function and, hence, correlation among vagally determined high frequency heart rate variability (HF-HRV), executive function, and regional cerebral blood flow (CBF). In 440 middle-aged men and women, resting HF-HRV was related to regional CBF derived from a resting arterial spin-labeled MRI scan and to seven neuropsychological tests of executive function. Despite some intercorrelations, regression modeling failed to support integrated central control of HF-HRV and executive function. Integration between autonomic and cognitive control appears more circumscribed than the general integration suggested by the neurovisceral integration hypothesis.

Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting‐state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega‐analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12–87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS—or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research. Impact Statement: Understanding which brain areas are associated with autonomic function has important clinical implications. Previous research was limited to small samples. Aiming for a thorough and large replication, we investigated n = 1,218 healthy subjects in a pooled mega‐analysis. We found unique associations between vagal activity and cortical thickness of frontal brain areas. It is suggested that greater integrity of prefrontal brain areas may be vital for the maintenance of adaptive autonomic nervous system activity in aging. [ABSTRACT FROM AUTHOR]

Life stressors during pregnancy can disrupt maternal stress regulation and negatively impact offspring health. Despite the important role of cardiac vagal control (e.g., heart rate variability; HRV) in stress regulation, few studies have investigated how life stressors and emotional support influence vagal control during pregnancy. This study aimed to (a) characterize patterns of cardiac vagal control in response to a stressor administered in pregnancy, and (b) examine the effects of life stress and emotional support on vagal control during rest, reactivity, and recovery. Participants included 191 pregnant women (79% Black; 21% White) living in an urban U.S. city (73% receiving public assistance). Heart rate (HR) and HRV (indexed by RMSSD) were recorded continually during the preparation, task, and recovery periods of the Trier Social Stress Test (TSST). Participants reported recent life stressors (e.g., relationship problems, financial hardship) and emotional support. Piecewise growth curve modeling was used to model rates of reactivity and recovery, adjusting for gestational age at time of assessment and recent health problems. Life stress predicted greater HR and HRV reactivity to the TSST as well as greater HRV recovery (vagal rebound). However, associations were only evident for women reporting high emotional support. Results suggest that pregnant women living with frequent life stressors may exhibit more rapid autonomic responses to acute stress, including more rapid vagal rebound after stressors, potentially reflecting physiological adaptation to anticipated high‐stress environments; emotional support may enhance these responses. Studies are needed to investigate long‐term health outcomes related to this stress response pattern. Impact Statement: Few studies have investigated how life stress influences cardiac vagal control during pregnancy. Our findings suggest that pregnant women living with frequent life stressors may exhibit more rapid vagal reactivity and recovery from acute stress, a pattern consistent with greater 'vagal flexibility'. However, associations were only evident for women reporting high emotional support. Emotional support may play a critical role in facilitating adaptive responses to stress during pregnancy, particularly among women experiencing frequent life stressors. [ABSTRACT FROM AUTHOR]

What can a speech reveal about someone's state? We tested the idea that greater stress reactivity would relate to lower linguistic cognitive complexity while speaking. In Study 1, we tested whether heart rate and emotional stress reactivity to a stressful discussion would relate to lower linguistic complexity. In Studies 2 and 3, we tested whether a greater cortisol response to a standardized stressful task including a speech (Trier Social Stress Test) would be linked to speaking with less linguistic complexity during the task. We found evidence that measures of stress responsivity (emotional and physiological) and chronic stress are tied to variability in the cognitive complexity of speech. Taken together, these results provide evidence that our individual experiences of stress or "stress signatures"-how our body and mind react to stress both in the moment and over the longer term-are linked to how complex our speech under stress.

The panic disorder (PD) literature provides evidence for both physiologic rigidity and instability as pathognomonic features of this disorder. This ambiguity may be a result of viewing PD at differential levels of temporal analysis. We assessed cardiac variability across three levels of temporal scale in PD patients, post-traumatic stress disorder (PTSD) patients, and healthy controls. Sixteen healthy controls, 14 PD patients, 23 PTSD patients, and 16 PTSD + PD patients presented for a polysomnogram. Differences were assessed in respiratory sinus arrhythmia (RSA), autoregressive stability of heart rate (HR), and the number of nonspecific accelerations in HR over the night. No differences in RSA were found between groups; however, PD patients exhibited significantly lower autoregressive HR stability, and all patients had significantly more HR accelerations than controls. These data reinforce prior findings demonstrating physiologic instability in PD and indicate that prior equivocalities regarding physiologic variability in PD may be due to limited temporal scaling of measurements.

The panic disorder (PD) literature provides evidence for both physiologic rigidity and instability as pathognomonic features of this disorder. This ambiguity may be a result of viewing PD at differential levels of temporal analysis. We assessed cardiac variability across three levels of temporal scale in PD patients, post-traumatic stress disorder (PTSD) patients, and healthy controls. Sixteen healthy controls, 14 PD patients, 23 PTSD patients, and 16 PTSD + PD patients presented for a polysomnogram. Differences were assessed in respiratory sinus arrhythmia (RSA), autoregressive stability of heart rate (HR), and the number of nonspecific accelerations in HR over the night. No differences in RSA were found between groups; however, PD patients exhibited significantly lower autoregressive HR stability, and all patients had significantly more HR accelerations than controls. These data reinforce prior findings demonstrating physiologic instability in PD and indicate that prior equivocalities regarding physiologic variability in PD may be due to limited temporal scaling of measurements.

Anxiety and depression are both characterized by dysregulated autonomic reactivity to emotion. However, most experiments until now have focused on autonomic reactivity to stimuli presented in central vision (CV) even if affective saliency is also observed in peripheral vision (PV). We compared autonomic reactivity to CV and PV emotional stimulation in 58 participants with high anxious (HA) or low anxious (LA) and high depressive (HD) or low depressive (LD) symptomatology, based on STAI‐B and BDI scores, respectively. Unpleasant (U), pleasant (P), and neutral (N) pictures from IAPS were presented at three eccentricities (0°: CV; −12 and 12°: PV). Skin conductance (SC), skin temperature, pupillary diameter, and heart rate (HR) were recorded. First, HA participants showed greater pupil dilation to emotional than to neutral stimuli in PV than in CV. Second, in contrast to HD, the valence effect indexed by SC and emotional arousal effect indexed by skin temperature were observed in LD. Third, both anxiety and depression lead to a valence effect indexed by pupillary light reflex and heart rate. These results suggest a hyperreactivity to emotion and hypervigilance to PV in anxiety. Depression is associated with an attenuation of positive effect and a global blunted autonomic reactivity to emotion. Moreover, anxiety mostly modulates the early processes of autonomic reactivity whereas depression mainly affects the later processes. The differential impact of emotional information over the visual field suggests the use of new stimulation strategies in order to attenuate anxious and depressive symptoms. The present contribution highlights the importance of using both central and peripheral vision in the study of autonomic reactivity to emotion. The main finding is the identification of anxiety and depression specific autonomic outputs according to stimuli position over the visual field and the emotional content of these stimuli. In addition, anxiety mostly modulates the early processes of autonomic reactivity whereas depression mainly affects the later processes. [ABSTRACT FROM AUTHOR]

Stress Recovery Theory (SRT) suggests that time spent in nature reduces stress. While many studies have examined changes in stress physiology after exposure to nature imagery, nature virtual reality, or nature walks, this study is the first to examine changes in heart rate (HR) and vagally mediated HR variability, as assessed by Respiratory Sinus Arrythmia (RSA), after a longer duration of nature exposure. Consistent with SRT, we hypothesized that immersion in nature would promote stress recovery, as indexed by an increase in RSA and a decrease in HR. We also predicted that exposure to nature would improve self‐reported mood. We used a within‐subjects design (N = 67) to assess changes in peripheral physiology before, during, and after a 5‐day nature trip. Results demonstrated a significant decrease in RSA and a significant increase in HR during the trip compared to before or after the trip, suggesting that immersion in nature is associated with a shift toward parasympathetic withdrawal and possible sympathetic activation. These results were contrary to our hypotheses and may suggest increased attentional intake or presence of emotions associated with an increase in sympathetic activation. We also found an improvement in self‐reported measures of mood during the trip compared to before or after the trip, confirming our hypotheses and replicating previous research. Implications of this study are discussed in the context of SRT. At a time when people are increasingly spending more time indoors, it is critical to examine the potential benefits of exposure to natural environments. This study is one of the first to measure changes in physiology during immersion in nature, which could have important implications for the protection of public lands as well as the individual. [ABSTRACT FROM AUTHOR]

The degree to which romantic partners' autonomic responses are coordinated, represented by their pattern of physiological synchrony, seems to capture important aspects of the reciprocal influence and co‐regulation between spouses. In this study, we analyzed couple's cardiac synchrony as measured by heart rate (HR) and heart rate variability (HRV). A sample of 27 couples (N = 54) performed a structured interaction task in the lab where they discussed positive and negative aspects of the relationship. During the interaction, their cardiac measures (HR and HRV) were recorded using the BIOPAC System. Additional assessment, prior to the lab interaction task, included self‐report measures of empathy (Interpersonal Reactivity Index and Interpersonal Reactivity Index for Couples) and relationship satisfaction (Revised Dyadic Adjustment Scale). Synchrony computation was based on the windowed cross‐correlation of both partner's HR and HRV time series. In order to control for random synchrony, surrogate controls were created using segment‐wise shuffling. Our results confirmed the presence of cardiac synchrony during the couple's interaction when compared to surrogate testing. Specifically, we found evidence for negative (antiphase) synchrony of couple's HRV and positive (in‐phase) synchrony of HR. Further, both HRV and HR synchronies were associated with several dimensions of self‐report data. This study suggests that cardiac synchrony, particularly, the direction of the covariation in the partners' physiological time series, may have an important relational meaning in the context of marital interactions. Our research extend previous empirical evidence on couple's physiological synchrony. By differentiating in‐phase from antiphase synchrony based on two cardiac metrics, our results showed the importance of examining not only the covariation between physiological time series, but also the direction of that covariation. By including surrogate data sets using segment‐wise shuffling to control for coincidental synchrony, we were able to derive a significant and reliable signature of cardiac synchrony during marital interaction. [ABSTRACT FROM AUTHOR]

Stressor‐evoked cardiovascular reactivity, trait positive emotionality, and negative emotionality are all associated with cardiovascular disease. It is unknown, however, whether cardiovascular reactivity may constitute a pathway by which trait positive or negative emotionality relates to disease risk. Accordingly, this study modeled the cross‐sectional relationships between trait positive and negative emotionality, stressor‐evoked cardiovascular reactivity, and severity of a subclinical vascular marker of cardiovascular risk, carotid artery intima‐media thickness (CA‐IMT). The sample consisted of healthy, midlife adults free from clinical cardiovascular disease (N = 286; ages 30–54; 50% female). Trait positive and negative emotionality were measured by three questionnaires. Heart rate and blood pressure reactivity were assessed across three stressor tasks. CA‐IMT was assessed by ultrasonography. Latent factors of positive and negative emotionality, blood pressure reactivity, heart rate reactivity, and CA‐IMT were created using structural equation modeling. Greater negative emotionality was marginally associated with more CA‐IMT (β =.21; p =.049), but lower blood pressure reactivity (β = −.19; p =.03). However, heightened blood pressure (β =.21; p =.03), but not heart rate reactivity (β = −.05; p =.75), associated with greater CA‐IMT. Positive emotionality was uncorrelated with cardiovascular reactivity (blood pressure: β = −.04; p =.61; heart rate: β =.16; p =.11) and CA‐IMT (β =.16; p =.07). Although trait negative emotionality associates with a known marker of cardiovascular disease risk, independent of positive emotionality, it is unlikely to occur via a stressor‐evoked cardiovascular reactivity pathway. It remains unclear whether positive or negative emotionality have separate or reciprocal associations with stress reactivity and cardiovascular disease risk. Our study demonstrates that trait negative emotionality is associated with lower blood pressure reactivity and cardiovascular disease risk, independent of trait positive emotionality. However, there was no evidence to suggest that trait negative emotionality is associated with cardiovascular disease risk via cardiovascular stress reactivity. [ABSTRACT FROM AUTHOR]