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Bruce Friedman, director of the Mind-Body Lab at Virginia Tech, describes neurophysiological models of anxiety and the psychophysiological approach for non-invasive assessment of autonomic activity in autism.

Neural entrainment is a phenomenon whereby neural oscillations adjust their frequency to synchronize with the periodic vibration of external stimuli. Research suggests that neural entrainment may help explain the relationship between music education and more optimal cognitive performance later in development. This dissertation tested whether sensory entrainment caused short-term cognitive and motor performance benefits in a young adult sample, and whether entrainment or performance were impacted by stimulus parameters like modality or rhythm or individual differences in attentional ability and music training. Participants (N= 47) were asked to report the extent and type (e.g. instrumental, vocal) of music experience and severity of ADHD symptoms, and then were exposed to repetitive 1.25-Hz or arrhythmic visual or auditory stimuli with interlaced Flanker test items, while EEG was recorded. At some points in the experiment participants were additionally tasked with tapping along to the 1.25-Hz beat through both beat stimuli and gaps. Some entrainment and performance effects were congruent with findings from prior literature, while many other hypotheses regarding entrainment effects were not supported. In terms of individual differences, neither music training nor ADHD symptoms impacted entrainment, but ADHD did impact the effects of entrainment stimuli on Flanker reaction time, with higher ADHD symptoms predicting worse performance during periods of rhythmic stimulation. Lastly and surprisingly, while neither entrainment, music training, nor ADHD symptoms impacted beat-keeping performance in general, ADHD symptoms predicted better beat-keeping during stimulus gap periods. Results in general paint a complicated picture of acute entrainment effects and individual differences. Doctor of Philosophy Neural entrainment is a phenomenon whereby neural oscillations adjust their frequency to synchronize with the periodic vibration of external stimuli. Research suggests that neural entrainment may help explain the relationship between music education and more optimal cognitive performance later in development. This dissertation tested whether sensory entrainment caused short-term cognitive and motor performance benefits in a young adult sample, and whether entrainment or performance were impacted by stimulus parameters like modality or rhythm or individual differences in attentional ability and music training. Participants (N= 47) were asked to report the extent and type (e.g. instrumental, vocal) of music experience and severity of ADHD symptoms, and then were exposed to repetitive 1.25-Hz or arrhythmic visual or auditory stimuli with interlaced Flanker test items, while EEG was recorded. At some points in the experiment participants were additionally tasked with tapping along to the 1.25-Hz beat through both beat stimuli and gaps. Some entrainment and performance effects were congruent with findings from prior literature, while many other hypotheses regarding entrainment effects were not supported. In terms of individual differences, neither music training nor ADHD symptoms impacted entrainment, but ADHD did impact the effects of entrainment stimuli on Flanker reaction time, with higher ADHD symptoms predicting worse performance during periods of rhythmic stimulation. Lastly and surprisingly, while neither entrainment, music training, nor ADHD symptoms impacted beat-keeping performance in general, ADHD symptoms predicted better beat-keeping during stimulus gap periods. Results in general paint a complicated picture of acute entrainment effects and individual differences.

In 2020, instances of anti-Black racism and racial injustice became increasingly prevalent and garnered widespread public attention. Simultaneously, the COVID-19 pandemic contributed to experiences of stress and elevated risk of exposure to maladaptive health outcomes. Black communities were disproportionately affected by these intersecting events, leaving them more vulnerable to increased stress and trauma, differential access to healthcare, and adverse mental health outcomes (Hooper et al., 2020; Schmitt et al., 2014; Vindegaard and Benros, 2020). In a sample of trauma-exposed Black adults residing in southwest Virginia, this mixed methods investigation examined the associations between psychopathology and exposure to COVID-19 and racial discrimination stressors, as well as between resilience/coping factors and psychological difficulties. Open-ended questions related to stressors, coping strategies, and mental health care perceptions and barriers were posed. Results indicated racial discrimination associated significantly with posttraumatic stress disorder (PTSD), depression and anxiety, and shame symptoms, whereas pandemic-related stress associated only with PTSD symptoms. Afrocentric worldview emerged as the most salient resilience factor negatively associated with psychopathology, followed by social support and resilient coping. Common barriers to care included a dearth in Black providers, feasibility factors, and limited availability of services, though the majority of the sample expressed a belief in mental health services as helpful. Future implications of this work include implementation of accessible, community-based resources, support for increased racial-ethnic representation among mental health providers, and incorporation of culturally-appropriate and client-centered strategies in existing evidence-based treatments. Doctor of Philosophy Shortly after the first declaration of COVID-19 as a global health pandemic, instances of racial injustice and police brutality captured national public attention. These intersecting stressors resulted in disproportionately elevated rates of poor health and economic outcomes, increased exposure to potentially traumatic events, and increased risk of mental health difficulties for Black Americans (Hooper et al., 2020; Schmitt et al., 2014; Vindegaard and Benros, 2020). In this investigation, 84 Black adults who reported living in southwest Virginia and had experienced at least one traumatic event in their lifetime completed an online survey. This survey included measures of exposure to traumatic events, COVID-19, and racial discrimination, psychological symptoms, and levels of coping and resilience. Participants also responded to a series of open-ended questions about stress, coping, and use of mental health services. Results of the investigation indicated that higher levels of racial discrimination were significantly associated with more posttraumatic stress disorder (PTSD), depression and anxiety, and shame symptoms, whereas higher COVID-19 stress only associated with greater PTSD symptoms. Of the resilience variables, having a stronger alignment with an Afrocentric worldview was most associated with lower psychopathology, followed by higher social support and resilient coping. This sample reported several barriers to accessing formal mental health care such as low rates of Black providers in their area, cost, stigma, and a limited availability of services. Despite identified barriers, participants generally reported an ability to access services and believed therapy could be helpful. Implications of these results include support for accessible, community-based resources designed to bolster mental health, the need for increased recruitment and retention of diverse racial-ethnic mental health workers, particularly in rural areas, and the use of culturally-sensitive strategies within existing evidence-based clinical services.

The ability to sense the internal state of one's body is the process of interoception and is a marker for positive emotional outcomes. The last five years have seen burgeoning research interest in interoception, including a call for more integrative and predictive biomarkers for interoceptive ability. While there is a robust literature purporting to measure interoception, there is also significant research challenging the content validity of the current methodology. Beyond these published challenges, I offer a broader critique that suggests that the current reductionist approach fails to capture the integrative nature of interoception. I introduce an alternate methodology to assess interoceptive ability that leverages the integrative nature of the autonomic nervous system. Thirty-four undergraduates provided real-time feedback about their subjective state of arousal while watching three videos of varying intensity. Across subjects, arousal feedback did not positively correlate with physiological indices of sympathetic arousal including electrodermal activity and the inverse of pre-ejection period. However, each subject appeared to have an idiographic pattern of physiological variables that correlated strongly, although often negatively, with the subjective slider feedback. These physiological patterns provide the foundation for investigating a new biomarker for interoception that relies on the autonomic nervous system to surmise interoceptive states. Doctor of Philosophy A person's sense of their body is called interoception. Research has shown that people who are good at interoception tend to live happier and more fulfilling lives. But current research techniques don't do a great job measuring whether someone is good at interoception. These techniques have faced a lot of criticism for the errors they are known to make. I add my concerns that the current techniques don't reflect how we naturally sense into our bodies when we're not in a lab. I explain why I think we need a new way of measuring interoception that captures how holistic this process is. I introduce a new measure that is based on the energy in our body. I believe that people use this energy system naturally and will also be better able to reflect this is a lab setting. The people in this study used a slider dial to indicate how much energy they felt while they watched videos with different excitement levels. While they watched the videos and moved the dial, we measured their bodily readings from their heart, breathing, and sweat to see if these readings matched their dial ratings. We were surprised that the typical body readings for excitement were not directly related to the slider movements when we averaged across people, but we did find that each person had their own unique way of responding that was similar in both mind and body. This research is the basis for a new way to understand how people read their own body, and how accurate this reading is.

Past research has demonstrated that emotions can accurately be communicated via touch (e.g., Hertenstein, Keltner, App, Bulleit, and Jaskolka, 2006). In stranger female dyads, physiological linkage plays a role in the mechanism whereby this successful communication occurs, as touch strengthens and lengthens linkage (Kissel, 2020). While touch has a direct impact on physiological processes, viewing touch may have similar effects. The current study explored this possibility in regard to physiological linkage. Hertenstein et al., 2006 demonstrated that participants can correctly decode emotions from observing videos of communication via touch to the forearm and hand. The current study replicated this finding with forty-seven female participants, while also determining the levels of physiological linkage between the "live" observers and the video-recorded participants from Kissel (2020) using dynamic linear time series modeling. Results showed that physiological linkage can occur between "live" and recorded participants. Participants demonstrated longer linkage times with the initial dyad they viewed, but linkage with videoed communicators whose communications were correctly perceived by their fellow videoed receiver had a larger influence on emotion word, valence, intensity, and quadrant detection accuracy. Based on these results, physiological linkage may influence empathic accuracy in virtual settings. Doctor of Philosophy A common American English slang expression to state that you relate to someone on a deep personal level is "I feel you." This is a verbal expression of empathy, but what if empathy goes deeper than our thoughts or memories of similar experiences? What if our bodies experience the same emotion as the person with whom we are interacting? This is possible through the phenomenon of "physiological linkage." Physiological linkage occurs when physiological signals, such as heart rate, between interaction partners start to sync up—for example, when one person's heart rate speeds up, so does the heart rate of the person with whom they are interacting. The author's thesis study demonstrated that this linkage can occur when people communicate emotions solely through touch. But what happens if you are watching these emotion communications instead of experiencing them? The current study examined if physiological linkage occurs between people watching a video and the people emoting in the video. The results showed that linkage does occur while watching emotional touch interactions and that this can help the observer understand what these emotions are (even if the observer can see no faces and hear no voices). Touch has many health benefits, so the observation that watching recorded touch interactions can have a similar bodily effect has implications for increasing health and connectedness. This is particularly important given the limited face-to-face and touch interactions, as well as the increase in video call interactions, resulting from the COVID-19 pandemic.

Theories of emotion regulation and social engagement indicate that resting and reactive respiratory sinus arrhythmia (RSA), which reflect vagal activity, in early childhood can inform the development of social and emotional behaviors later in life. Low RSA at baseline and during a stressful task have been associated with symptoms of ED and disorders characterized by social impairments. The current study examined the mediating role of ED at 24-months-old (mo) on the prospective association between early infant resting and reactive RSA at 5 mo on social functioning outcomes at 48 mo, and the mediating role of social functioning at 24 mo on infant RSA at 5 mo and ED at 48 mo in 237 healthy children. It was hypothesized that ED would mediate the relationship between infant RSA and later childhood social function. Results largely indicated no support of the hypotheses and that there is no mediating effect of childhood ED on early RSA on later childhood social behavior; however, there was a significant relationship between infant resting and reactive RSA and later ED. Limitations and future directions for improving the methodology are addressed. M.S. Early childhood heart rate has been thought to influence the development of later child emotional and social development. The Polyvagal Theory suggests that low variability in heart rate, as measured by respiratory sinus arrhythmia (RSA), is related to greater difficulties in emotional and social behavior. Finding an underlying biological reason for emotional and social development can be important for understanding childhood psychological disorders. This research study examined healthy children at three different time points during development: 5 months old (mo), 24 mo, 48 mo. RSA was measured at 5 mo, and frustration levels and social abilities at 24 and 48 mo. It was hypothesized that low RSA at 5 mo predicts low social abilities at 48 mo because of high frustration levels at 24 mo. To rule out an alternate hypothesis, this study also tested if low RSA at 5 mo predicts high frustration levels at 48 mo because of low social abilities at 24 mo. The results of this study did not support the predictions and there was no evidence of emotional abilities affecting how RSA predicts later social abilities. Possible explanations for the lack of findings and ideas for future research were discussed.

Although the negative consequences of traumatic exposure across various domains of functioning have been well-documented, gaps and discrepancies continue to exist in the understanding of the impact of complex trauma, such as interpersonal violence (IPV), and how outcomes may vary across diverse populations and identities. In this cross-sectional study investigating the impact of traumatic exposure on physiological domains of functioning, a sample of female-identifying college students completed a number of self-reported measures (assessing past and present trauma exposure, complex posttraumatic stress disorder [CPTSD] symptoms, racial-ethnic minority status, and age of onset of first traumatic exposure) and provided resting high-frequency heart rate variability (hfHRV) data, which served as a biomarker for the potential impact of trauma exposure on physiological domains. Correlational and multiple regression analyses were conducted to determine the strength of relationships between variables and the predictive value of the models. Results indicated endorsement of IPV trauma was significantly associated with earlier age of onset, more severe levels of CPTSD symptoms, and higher hfHRV, but not racial-ethnic minority status. Racial-ethnic minority status was significantly related to more severe CPTSD symptoms. Type of trauma exposure was the only variable that emerged as having predictive value for changes in hfHRV. These findings suggest that experiencing IPV may have unique implications for trauma symptomatology and functioning above and beyond other forms of traumatic exposure, but that continued research must be conducted in order to draw more robust conclusions about the effects of exposure on physiological regulation across various racial-ethnic identities. M.S. Research has highlighted the consequences that extremely negative, stressful experiences, also called traumatic events, can have on the way humans think, emote, behave, and physically react. It can be more difficult to draw conclusions about the effects of interpersonal violence (IPV), or violence that occurs at the hands of another (i.e., family, partner, or community violence), due to the complex, severe, and long-term nature of symptoms that survivors experience. There is also limited research about what complex trauma looks like across diverse populations. This study aimed to investigate the impact of traumatic exposure on physiology, which falls under biology and broadly includes the functions of living things. A sample of female-identifying college students completed a number of self-reported measures (assessing trauma exposure, complex posttraumatic stress disorder [CPTSD] symptoms, racial-ethnic minority status, and age of onset of first traumatic exposure) and provided resting high-frequency heart rate variability (hfHRV) data, which measures variation in time between beats and served as a measure for the potential impact of trauma exposure on physiology. Results suggested that IPV exposure was associated with earlier age of first traumatic experience, more severe levels of CPTSD symptoms, and higher hfHRV. Racial-minority status was significantly related to more severe CPTSD symptoms. Type of trauma exposure significantly predicted changes in hfHRV. Findings suggest that experiencing IPV may uniquely influence trauma symptoms and functioning above and beyond other forms of traumatic exposure. Continued research will allow for stronger conclusions about the effects of traumatic exposure on physiology across various racial-ethnic identities.

The Generalized Unsafety Theory of Stress proposes that physiological markers of generalized stress impair learning of safe cues in stressful environments. Based on this model, chronic problems inhibiting physiological arousal lead to a heightened perception of threat, which involves experiencing anxiety symptoms without any obvious precipitating stressful or traumatic event. This investigation aims to determine the impact of stressor- versus context-related emotional learning on generalized unsafety, using a Pavlovian threat-conditioning paradigm. The difference in learning threatening cues ([CS+] paired with an aversive stimulus) compared to safety cues ([CS-] not paired with an aversive stimulus) was used as a proxy measure of generalized unsafety, as conceptualized by the GUTS model. This difference is expected to be moderated by individual differences in tonic cardiac regulation (i.e. heart rate variability). Lastly, a temporal-differences learning model was used to predict skin-conductance learning during stressor, stressor context and general contexts to determine which best predicts Pavlovian learning. TD learning is expected to better predict skin-conductance in individuals with higher fear inhibition in comparison to those with low fear inhibition. Doctor of Philosophy This study examined the claims of a theory about how human bodies respond to stress and what this tells us about how anxiety develops in and affects the mind and body. The theory is named the Generalized Unsafety Theory of Stress (GUTS) and two main hypotheses were tested in this study: 1) the theory suggests that a person's feeling of safety is affected by the variation in their heart rate at rest, and 2) that a person's feeling of safety could be observed most accurately by their body's defense responses when they are experiencing a threatening situation that is objectively safe. Individuals experiencing anxiety often report being aware that they are safe, yet their heart rate remains elevated and palms remain sweaty. Most studies that have examined the body's defense response have focused almost solely on reactions to a threat by looking at the reactions of one or more organs that make up the body's defense-response systems (e.g., heart). Results of this study confirmed the unique GUTS perspective. Specifically, the heart rate's variation at rest affects the defense response (sweaty hands) during threatening and objectively safe contexts, which in turn, predicts a person's feeling of safety. These results confirm that there are measurable biological constraints that change the way people learn about and react to their environments, which is very important for understanding the development and maintenance of anxiety physiology and behavior. The way a person learns to associate emotional responses to certain cues in their environment, particularly threat and safety cues, can be measured as defense responses in the body in response to a series of trials. Exploratory analyses examined human threat learning in comparison with mathematically-generated learning in order to better model the processes whereby anxiety develops based on learning of threat and safety cues.

Previous research has demonstrated that communication of emotion via touch is possible and occurs well-above chance levels, though the potential mechanism whereby this occurs has yet to be determined. The current study aimed to determine if physiological linkage, or the synchrony between various physiological signals between two interaction partners, played a role in successful communication of emotion via touch. Dynamic linear times series analysis was used to determine the strength and length of synchrony between the inter-beat intervals of fifty-two stranger female-female dyads (n=104, mean age=19.88) during two rounds of an emotion communication task in which they communicated a randomized list emotions to each other via forearm touch alone without being able to see their interaction partner. Results showed the highest magnitude linkage coefficients and the greatest number of consecutive lagged linked seconds during the “touch alone” communication—demonstrating that touch increases physiological linkage. Stronger and longer physiological linkage across tasks predicted emotion word, valence, intensity, and quadrant (from the circumplex model) detection accuracy. Participants serving as the initial communicator in the first round of emotion communication tended to have a greater influence on the physiology of initial receivers. Overall, greater physiological linkage as the result of touch predicted successful communication of emotion via touch and is therefore likely a portion of the mechanism underlying this phenomenon. M.S. People often communicate with their friends, family, and acquaintances using touch—when meeting a loved one after a long time, we might give them a particularly tight hug; to congratulate someone, we give a high five; and even in business settings, handshakes are used as a form of greeting or parting. Touch can also be used to communicate distinct emotions, just like a frown or a stern tone can communicate visually and aurally that someone is angry. However, although past research has demonstrated this communicative ability of touch, it is not yet known how touch is able to communicate emotion. The current study hypothesized that physiological linkage might play a role. Physiological linkage occurs when physiological signals, such as heart rate, between interaction partners starts to sync up—for example, when one person’s heart rate speeds up, so does the heart rate of the person with whom they are interacting. Results showed that greater levels of physiological linkage occurred in response to touch and that these increased levels of physiological linkage predicted people’s ability to successfully determine which emotion was communicated to them via touch to their forearm. All the emotions were communicated via touch alone; participants could not see or hear their interaction partner. This demonstrates how powerful communication via touch can be. Future research should examine how touch and physiological linkage can be incorporated into medical and psychological therapies.

PTSD is a moderately heritable disorder that causes intense and chronic suffering in many afflicted individuals. The pathogenesis of PTSD is not well understood, and genetic mechanisms are particularly elusive. Neurotransmitter systems are thought to contribute to PTSD etiology and are the targets of most pharmacotherapies used to treat PTSD, including the only two FDA approved options and a wide array of off-label options. However, the degree to which variation in genes which encode for and regulate neurotransmitter receptors increase risk of developing PTSD is unclear. Recently, large collaborative groups of PTSD genetics researchers have completed genome-wide association studies (GWAS) using massive sample sizes and have made summary statistics available for public use. In 2018, a new technique for high-powered analysis of GWAS summary statistics called GSA-SNP2 was introduced. In order to explore the relationship between PTSD and genetic variants in widely theorized molecular targets, this study applied GSA-SNP2 to manually curated neurotransmitter receptor gene-sets. Curated gene-sets included nine total "neurotransmitter receptor group" gene-sets and 45 total "receptor subtype" gene-sets. Each "neurotransmitter receptor group" gene-sets was designed to capture concentration of genetic risk factors for PTSD within genes which encode for all receptor subtypes that are activated by a given neurotransmitter. In contrast, "receptor subtype" gene-sets focused on specific subtypes and also accounted for intracellular signaling; each was designed to capture concentration of genetic risk factors for PTSD within genes which encode for specific receptor subtypes and the intracellular signaling proteins through which they exert their effects. Due to practical considerations, this work used summary statistics derived from a GWAS with far fewer participants (2,424 cases; 7,113 controls) than initially planned (23,212 cases; 151,447 controls). Prior to controlling for multiple comparisons, 7 of the investigated gene-sets reached statistical significance at the p ≤ .05 level. However, after controlling for multiple comparisons, none of the investigated gene-sets reached statistical significance. Due to limited statistical power of the current work, these results should be interpreted very cautiously. The current study is best interpreted as a preliminary study and is most informative in relation to refining study design. Implications for next steps are emphasized in discussion and nominally significant results are synthesized with the literature to demonstrate the types of research questions that might be addressed by applying a refined version of this study design to a larger sample. Doctor of Philosophy Though nearly all individuals will be exposed to a potentially traumatic event in their lifetime, only a small percentage will experience PTSD, which is a severe psychological disorder. Though genetics are known contribute to an individual's level of risk for developing PTSD, relatively little is known about which particular genetic differences are key. Neurotransmitter receptors are thought to contribute to the risk for PTSD and are a key aspect of medications for PTSD. However, little is known about whether genetic differences in neurotransmitter receptors contribute to risk for developing PTSD. Recently, large collaborative groups of PTSD genetics researchers have completed studies which investigate genetic risk factors from across the genome using massive sample sizes and have made the statistical output of these studies available to the public. In 2018, a new technique called GSA-SNP2 was created to help assist with efforts to analyze aspects of that statistical output that have not been previously analyzed. This study used GSA-SNP2 to analyze the degree to which groups of neurotransmitter receptor genes contribute to the risk of developing PTSD. Due to the coronavirus pandemic, the researcher did not have access to the computing power needed to analyze the initially planned data which included 23,212 individuals with PTSD and 151,447 individuals without PTSD. As a substitute, the current work is an analysis using statistical output data from a study which included 2,424 individuals with PTSD and 7,113 individuals without PTSD. Based on a level of statistical significance that is typically used in most psychological studies, seven of the investigated gene-sets contribute highly to the risk for PTSD. However, it was necessary to use a different threshold for statistical significance due to the testing of many different groups of genes. After making that adjustment, none of the investigated gene-sets reached statistical significance. Due to limited statistical power of the current work, these results should be interpreted very cautiously. The current study is best interpreted as a preliminary study and is most informative in relation to refining study design. Implications for next steps are emphasized in discussion and nominally significant results are synthesized with the literature to demonstrate the types of research questions that might be addressed by applying a refined version of this study design to a larger sample.

While it is estimated that 30% of the total Autism Spectrum Disorder (ASD) population acquire very little or no language (Davis et al., 2011), few studies look at ASD treatment from a mental or emotional health perspective for this minimally verbal (MV) population (Tager-Flusberg and Kasari, 2013). It is well documented that there is a need for anxiety assessment and treatment for children with ASD (White, Oswald, Ollendick and Scahill, 2009). This study examined the feasibility of implementing an observational anxiety assessment and concurrent physiological data collection for children with MV-ASD. It was hypothesized that this measure would demonstrate adequate demand, acceptability, and feasibility to merit further study of the measure. Participants consisted of 12 children with MV-ASD and one parent. Each family visited the clinic for one three-hour visit during which the parent completed several questionnaires to assess the child's eligibility for the study as well as their current functioning. Children completed several clinician-administered assessments and observations. The results of this study suggest that this observational assessment protocol is acceptable and practical per parents self-report and the amount of children able to complete the study protocol, but there may not be enough demand for such a measure based on the number of interested participants. Additionally, the concurrent collection of physiological data was not practical in the current sample due to many children scoring too high on a measure of tactile sensitivity to attempt this data collection. Future studies should more carefully assess demand for this kind of assessment, as well as collect more data on the psychometric properties of such as measure. Doctor of Philosophy Many children with Autism Spectrum Disorder or ASD, also experience a lot of anxiety or even an anxiety disorder. Unfortunately, many children with ASD also have a lot of difficulty learning to talk. When children with ASD can't speak to tell people how they are feeling it can make the diagnosis of anxiety really difficult. This project sought to use physical signs such as heart rate in combination with observing behaviors related to anxiety to see if we could better measure anxiety in children with ASD who can't talk. This was a feasibility study meaning that the goal of this project was just to see if the anxiety assessment process was possible and practical for these children to complete. 12 children with ASD and one of their parents participated in the study. They came to the clinic for three hours and completed some anxiety measures given by a clinician and some questionnaires. Our results suggested that some aspects of the anxiety assessment process are possible and helpful, such as the number of children who were able to complete the assessment process, but others aspects need more work before they are helpful, such as the collection of heart rate.

Understanding physiological responses to threat can inform therapeutic interventions for phobias, anxieties, and PTSD. The defense cascade is reviewed as a theoretical model that predicts behavioral and physiological responses to threats. Nineteen undergraduates (five male), average age 19.4 experienced a novel virtual reality (VR) threat scenario while their physiology was measured. The Subjective Units of Distress Scale (SUDS) was used as a self-report indicator of distress in the research setting. Averaged SUDS reports suggested that the VR stimulus was experienced as threatening for most participants, but their autonomic response patterns did not fit those predicted by the defense cascade. Participants who had scored high on adaptive response questionnaires tended to show uncoupled ANS activation during baseline, but varied across the stimulus condition. Nearly all participants showed either coactivation or reciprocal activation during the stimulus period except those reporting the most dissociative trauma experiences, who mostly showed uncoupled ANS activation. M.S. The more we understand about how people’s bodies and their energies act when they feel threatened, the better we can find help for folks who struggle with anxiety, trauma or other challenging conditions. This research uses a theoretical model called the defense cascade to explore how people respond mentally and physically to threatening situations. Nineteen undergraduates went through a virtual reality (VR) experience that was designed to feel threatening while their body and its energy systems were measured. A scale was introduced called the Subjective Units of Distress Scale (SUDS) and was used to help the researchers understand how distressed people felt while they were in the VR experience. Averaged SUDS reports suggested that the VR stimulus was experienced as threatening for most participants, but their body response patterns did not fit those predicted by the defense cascade. Participants whose questionnaire responses suggested they were not anxiety-prone or traumatized, tended to show bodily activation that uncoupled their two autonomic bodily systems during a baseline period before the threatening stimulus. However, their autonomic responses during the stimulus period varied. Nearly all participants showed either both autonomic systems acting together or only one system acting in a mutually exclusive way to the other system during the stimulus period. This was the case for most participants except those reporting the most trauma involving dissociative experiences. This latter group mostly showed uncoupled autonomic bodily patterns.

Social cognition is a set of complex processes that mediate much of human behavior. The development of these skills is related to and interdependent on other cognitive processes, particularly inhibitory control, which allows for willful suppression of dominant responses. Many aspects of social behavior rely on inhibitory control to moderate impulsive or socially inappropriate behaviors and process complex perspective-taking. Furthermore, the brain regions associated with inhibitory control and social cognition overlap functionally and structurally. I review neurodevelopmental literature to suggest that social cognition is developmentally dependent on inhibitory control and that the neural foundations of both these skills are measurable in infancy. I tested this model using growth curve and structural equation modeling and show that 10-month, but not 5-month, frontotemporal coherence predicts social cognition in late childhood through preschool inhibitory control. These findings provide insight into the neurodevelopmental trajectory of cognition and suggest that connectivity from frontal regions to other parts of the brain is a foundation for the development of these skills. Doctor of Philosophy Social cognition is the ability to understand and interpret another’s thoughts, words, and actions and inhibitory control is the ability to suppress one’s own thoughts, words, and actions. These two types of cognition are similar and use the same brain regions, and I suggest that inhibitory control underlies much of social cognition. In order to test this, I examined children’s inhibitory control and brain connectivity at 5 months, 10 months, 24 months, 48 months, and 9 years and measured social cognition at 9 years. I found that connectivity between the frontal and temporal lobes at 10 months predicted inhibitory control and 48-months, which then predicted social cognition at 9 years. This suggests that infant brain connectivity sets the stage for developing inhibitory control, which is important for later social cognition

The neurovisceral integration model (NVM) proposes that an organisms ability to flexibly adapt to their environment is related to biological flexibility within the central autonomic network. One important aspect of this flexibility is behavioral inhibition (Thayer and Friedman, 2002). During a behavioral inhibition task, the central autonomic network (CAN), which is comprised of a series of feedback loops, must be able to integrate information and react to these inputs flexibly to facilitate optimal performance. The functioning of the CAN is shown to be associated with respiratory sinus arrhythmia (RSA), as the vagus nerve is part of this feedback system. While the NVM has been examined through neural imaging and RSA, only a few studies have examined these measures simultaneously during the neuroimaging procedure. Furthermore, these studies were done at rest or used tasks that were not targeted at processes associated with the NVM, such as behavior inhibition and cognitive flexibility. For this reason, the present study assessed RSA and neural activation in the prefrontal cortex simultaneously while subjects completed a behavior inhibition task. Using a series of go/no-go tasks, RSA and functional near-infrared spectroscopy (fNIRS) were collected to investigate the relationship between prefrontal activation and vagal activity at rest and during behavioral inhibition. There are three primary aims of this study. First, examine prefrontal activation during various inhibition tasks through fNIRS. Second, evaluate the NVM during a cognitive task using simultaneous fNIRS and RSA analysis. Third, relate task performance, imaging, and RSA measures during behavioral inhibition to deficits in flexible everyday responding, as indicated by self-report measures of behavior. Doing so will elucidate the connection with prefrontal activation and RSA as proposed by the NVM model and determine whether neural and RSA metrics can be related to broader symptoms of inflexibility. PHD The neurovisceral integration model (NVM) proposes that the ability to adapt to the environment is related to biological flexibility within the brain. One important aspect of the ability to adapt to the environment is behavior inhibition (e.g., the ability to stop from engaging in a habitual response, Thayer & Friedman, 2002). During a behavior inhibition task, the brain must be able to integrate information and react to these inputs flexibly to facilitate optimal performance. The brain’s ability to do this is related to a measure of heart activity known as respiratory sinus arrhythmia (RSA). The present study assessed RSA and brain activity while subjects completed a behavior inhibition task. Neural activation was measured through functional near-infrared spectroscopy (fNIRS). fNIRS measures the amount of oxygenated blood in different areas of the brain. Greater concentrations of oxygenated blood indicated greater brain activity in an area. Through simultaneous fNIRS and RSA measurement the present study examined their relationship during various inhibition tasks. Doing so clarified the connection between brain activation and RSA as proposed by the NVM model.

Interoception, the perception of the body's physiological state, is often studied in relation to emotion processing. Particularly, cardioception has been largely implicated in anxiety. Three related but distinct dimensions of interoception have recently emerged in the literature: sensibility (IS), accuracy (IAC), and awareness (IAW). Divergent findings regarding interoception and anxiety may result from lacking appreciation for interoceptive dimensions. Additionally, the role of cardiovascular afferent feedback in anxiety and interoception is largely unknown. Baroreflex sensitivity (BRS) has been implicated in interoceptive processes yet no known research directly measures this in relation to multidimensional cardioception. The present study aimed to assess the degree to which IS, IAC, IAW, and BRS predict trait anxiety at rest and during anticipatory anxiety. Results partially suggest increased IAC and BRS, but more variable IS and IAW in relation to trait anxiety. Overall, results show complex associations among factors, suggesting increased specificity among the constructs. Results highlight the importance of attention to construct validity and method variance in the study of interoceptive subdomains. Finally, the present study helps to pave the way for continued investigations concerning cardioception in enduring anxiety and the related role of the baroreflex in cardiac afferent processes. PHD Interoception, the perception of the body’s physiological state, is often studied in relation to emotion processing. Particularly, cardioception (the sense of cardiac activity, such as the perception of a racing heart) has been largely implicated in anxiety. Three related but distinct dimensions of interoception have recently emerged in the literature: sensibility (IS), accuracy (IAC), and awareness (IAW). Divergent findings regarding interoception and anxiety may result from lacking appreciation for interoceptive dimensions. Additionally, the role of cardiovascular feedback to the brain in anxiety and interoception is largely unknown. The baroreflex system rapidly modulates activity of the heart in accordance with short-term blood pressure changes. The sensitivity of this homeostatic baroreflex system (BRS) also plays a role in interoceptive processes, yet no known research directly measures this in relation to multidimensional cardioception. The present study aimed to assess the degree to which IS, IAC, IAW, and BRS predict dispositional anxiety at rest and during anticipatory anxiety. Results partially suggest increased IAC and BRS, but more variable IS and IAW in relation to dispositional anxiety. Overall, results show complex associations among factors, suggesting increased specificity among the variables. Results highlight the importance of attention to measurement precision and various ways to assess the dimensions of interoception. Finally, the present study helps to pave the way for continued research concerning perception of the heart’s activity in enduring anxiety and the related role of cardiovascular activity at various levels of conscious awareness. Ultimately, research on this topic is highly important for the eventual improvement of existing therapeutics for individuals regularly experiencing severe anxiety.