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The Trier Social Stress Test (TSST) is a reliable biopsychological tool to examine the effects of acute stress on psychological and physiological functioning in humans. While the TSST reliably increases hypothalamic-pituitary-adrenal axis activation, amongst other biomarkers, through a combination of social evaluative threat and uncontrollability, the original protocol is limited in methodological detail that has impacted its reproducibility. Although many studies include a mock job interview and surprise arithmetic task, there are large variations in the timing of events, the number and method of biological (e.g., cortisol) sampling, the administration of a glucose drink, set-up of equipment and rooms, panel composition, and panel interaction with participants. We provide an overview of the potential impact of methodological variations on the stress (cortisol) response. Importantly, we also provide a step-by-step guide as a laboratory manual on how to conduct the TSST. This introductory guide may be a useful and time-saving resource that may also improve the scientific standard and reliability of the reported psychobiological stress effects in future studies.

Oxytocin (OXT) is a neuropeptide which has a critical role in human social behaviour and cognition. Research investigating the role of OXT on functional brain changes in humans has often used task paradigms that probe socioemotional processes. Preliminary evidence suggests a central role of the amygdala in the social cognitive effects of intranasal OXT (IN-OXT), however, inconsistencies in task-design and analysis methods have led to inconclusive findings regarding a cohesive model of the neural mechanisms underlying OXT's actions. The aim of this meta-analysis was to systematically investigate these findings. A systematic search of PubMed, PsycINFO, and Scopus databases was conducted for fMRI studies which compared IN-OXT to placebo in humans. First, we systematically reviewed functional magnetic resonance imaging (fMRI) studies of IN-OXT, including studies of healthy humans, those with clinical disorders, and studies examining resting-state fMRI (rsfMRI). Second, we employed a coordinate-based meta-analysis for task-based neuroimaging literature using activation likelihood estimation (ALE), whereby, coordinates were extracted from clusters with significant differences in IN-OXT versus placebo in healthy adults. Data were included for 39 fMRI studies that reported a total of 374 distinct foci. The meta-analysis identified task-related IN-OXT increases in activity within a cluster of the left superior temporal gyrus during tasks of emotion processing. These findings are important as they implicate regions beyond the amygdala in the neural effects of IN-OXT. The outcomes from this meta-analysis can guide a priori predictions for future OXT research, and provide an avenue for targeted treatment interventions.

This study explored the interrelationship between intolerance of uncertainty, sensory hyper-sensitivity and anxiety in Williams syndrome (WS). Thirty-two parents or guardians of individuals with WS (Mage = 24.76 years, SD = 7.55) were included. Associations between anxiety, intolerance of uncertainty, sensory hyper-sensitivity, and ASD symptoms were assessed. Linear regression analysis revealed that intolerance of uncertainty and sensory hyper-sensitivity were unique independent predictors of anxiety, while social communication score was not. There was evidence of a mediating effect of sensory hyper-sensitivity on the relationship between intolerance of uncertainty and anxiety. These findings bear strong resemblance to the pattern seen in ASD and emphasize the need for development of anxiety interventions that attempt to reduce negative beliefs about unpredictable situations in WS.

Background. Navigating obstacles whilst walking might be associated with poorer balance and a higher risk of falling in individuals with symptomatic Huntington’s disease (symp-HD). However, this issue has not been investigated within the literature. Objective. A unique obstacle navigation experiment was designed to examine adaptive gait patterns in order to identify spatiotemporal gait characteristics that might be associated with poorer balance and a higher risk of falling in symp-HD. Method. Sixteen diagnosed symp-HD participants and 16 age- and sex-matched healthy controls were included. Gait was examined in 3 experimental conditions: baseline walking, walking while navigating around 1 obstacle, and walking while navigating around 2 obstacles. Navigation around obstacle walks was divided into three step phases (approach, navigation, recovery). Group differences in gait variables were analyzed at baseline and during walking for each obstacle condition respectively. Gait variables were also correlated with the Berg Balance Scale (BBS) and Timed Up and Go (TUG) test. Results. Symp-HD participants, compared with controls, performed significantly poorer on most gait variables during baseline walking. Symp-HD participants significantly decreased their step-length while navigating around 1 obstacle, and increased their step-time while navigating around 1 and 2 obstacles. There were no significant group differences in step-width. Variables associated with navigating around obstacles correlated significantly with BBS and TUG clinical tools, which have been associated in the literature with an increased risk of falling in symp-HD. Conclusion. These findings could aid clinicians in better managing risk of falls in people with Huntington’s disease through targeted and effective strategies.

Background: Family functioning in Huntington’s disease (HD) is known from previous studies to be adversely affected. However, which aspects of family functioning are disrupted is unknown, limiting the empirical basis around which to create supportive interventions. Objective: The aim of the current study was to assess family functioning in HD families. Methods: We assessed family functioning in 61 participants (38 HD gene-expanded participants and 23 family members) using the McMaster Family Assessment Device (FAD; Epstein, Baldwin and Bishop, 1983), which provides scores for seven domains of functioning: Problem Solving; Communication; Affective Involvement; Affective Responsiveness; Behavior Control; Roles; and General Family Functioning. Results: The most commonly reported disrupted domain for HD participants was Affective Involvement, which was reported by 39.5% of HD participants, followed closely by General Family Functioning (36.8%). For family members, the most commonly reported dysfunctional domains were Affective Involvement and Communication (both 52.2%). Furthermore, symptomatic HD participants reported more disruption to Problem Solving than pre-symptomatic HD participants. In terms of agreement between pre-symptomatic and symptomatic HD participants and their family members, all domains showed moderate to very good agreement. However, on average, family members rated Communication as more disrupted than their HD affected family member. Conclusion: These findings highlight the need to target areas of emotional engagement, communication skills and problem solving in family interventions in HD.

Opiate use is associated with deficits in decision-making. However, the impact of abstinence and co-morbid factors, like head injury and poly-substance abuse, on this ability, is currently unclear. This meta-analysis aimed to assess 1) the magnitude of decision-making deficits in opiate users; 2) whether co-morbid factors moderate the severity of these deficits; 3) whether ex-opiate users demonstrate smaller decision-making deficits than current users; and 4) whether the length of abstinence is related to the magnitude of decision-making deficits. We analysed 22 studies that compared the performance of current and ex-opiate users to healthy controls on decision-making measures such as the Iowa Gambling Task. Current users demonstrated a moderately strong impairment in decision-making relative to controls, which was not significantly moderated by co-morbid factors. The magnitude of the impairment did not significantly differ between studies assessing current or ex-users, and this impairment was not related to length of abstinence. Thus, it appears that opiate users have relatively severe decision-making deficits that persist at least 1.5 years after cessation of use.

Huntington’s disease (HD) is a neurodegenerative movement disorder associated with deficits in the processing of emotional stimuli, including alterations in the self-reported subjective experience of emotion when presented with pictures of emotional scenes. The aim of this study was to determine whether individuals with HD, compared to unaffected controls, display abnormal visual scanning of emotionally-evocative natural scenes. Using eye-tracking, we recorded eye-movements of 25 HD participants (advanced pre-symptomatic and early symptomatic) and 25 age-matched unaffected control participants during a picture viewing task. Participants viewed pictures of natural scenes associated with different emotions: anger, disgust, happiness, or neutral, and evaluated those pictures on a valence rating scale. Individuals with HD displayed abnormal visual scanning patterns, but did not differ from controls with respect to their valence ratings. Specifically, compared to controls, HD participants spent less time fixating on the pictures and made longer scan paths. This finding highlights the importance of taking visual scanning behavior into account when investigating emotion processing in HD. The visual scanning patterns displayed by HD participants could reflect a heightened, but possibly unfocussed, search for information, and might be linked to attentional deficits or to altered subjective emotional experiences in HD. Another possibility is that HD participants may have found it more difficult than controls to evaluate the emotional valence of the scenes, and the heightened search for information was employed as a compensatory strategy.

Chronic neck and shoulder pain (CNSP) is a common musculoskeletal disorder in adults, which is linked to hypersensitivity to noxious stimuli. The hormone oxytocin has been implicated as a potential therapeutic for the management of chronic pain disorders, and has been suggested to have sex-specific effects on the salience of threatening stimuli. This study investigated the influence of intranasal oxytocin on the perception of noxious thermal stimuli. Participants were 24 individuals with CNSP lasting >12 months (eight women), and 24 age- and sex-matched healthy, pain-free controls. In a randomised double-blind, placebo-controlled, cross-over study, participants attended two sessions, self-administering intranasal oxytocin (24 IU) in one session, and placebo in another. Participants rated intensity and unpleasantness of thermal heat stimuli at three body sites: the cervical spine, deltoid, and tibialis anterior, on 11-point numerical rating scales. Compared with placebo, intranasal oxytocin increased the perceived intensity of noxious heat stimuli in women with CNSP (Cohen’s d = 0.71), but not in men with CNSP, or healthy, pain-free controls. Men and women displayed divergent sensitivity across target sites for ratings of pain intensity (partial eta squared = 0.12) and pain unpleasantness (partial eta squared = 0.24), irrespective of drug condition. Men were more sensitive at the cervical spine and deltoid, whereas women were more sensitive at the tibialis. These findings suggest that oxytocin and endogenous sex hormones may interact to influence the salience of noxious stimuli. The hyperalgesic effects of oxytocin in women suggest that caution should be taken when considering oxytocin in the management of chronic pain. Trial Registration: CT-2016-CTN-01313-1; ACTRN12616000532404

Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disorder. The most prominent sign of HD is the presence of involuntary motor movements. However, HD is also characterized by marked cognitive decline, which often precedes the onset of motor symptoms and is generally considered to be more debilitating to the patients and their families, compared to motor symptoms. Cognitive decline is widespread across most faculties of cognition in later stages of the disease, but seems to be selective in preclinical and early stages of the disease, with deficits in the HD patients' ability to multitask, their speed of processing, and executive function. It is now well established that preceding clinical diagnosis there is a preclinical stage, during which HD gene mutation carriers are relatively symptom free, despite disease pathological onset and the presence of neurodegeneration. Evidence from functional brain imaging studies suggests the presence of neural compensation in preclinical stages of HD, whereby the brain undergoes functional reorganization in response to neurodegeneration to preserve motor and cognitive performance. In this review, we will describe the underlying HD pathology with a focus on how it links to the cognitive phenotype. We will also present evidence regarding the presence of neural compensation in HD and the possible mechanisms supporting it. Finally, we will discuss current research in the field of cognitive interventions that aim to support and enhance neural compensation in HD. These research efforts could, one day, prolong the preclinical stage and assist with symptom management of those affected with HD.

Body Dysmorphic Disorder (BDD) is characterised by overvalued or delusional beliefs of 'imagined ugliness'. Delusional beliefs have been explained by a number of cognitive theories, including faulty perceptions, biases in attention, and corruption of semantic memory. Atypical aesthetics may also influence beliefs in BDD. In fourteen BDD patients, compared to controls (n=14), we examined these theories of beliefs in a cognitive test battery consisting of perceptual organisation and visual affect perception tasks, a Stroop task using body words, a sentence verification task, a fluency task, and an attractiveness task. BDD patients performed similar to controls on tasks measuring information (bias) processing and aesthetics. However, BDD showed abnormal abilities on semantic processing involving sentence verification and category fluency. There was only a trend finding of impaired performance on perceptual processing tasks in BDD. The findings suggest that the delusional beliefs in BDD may be explained by impaired semantic processing.

Evidence now suggests executive dysfunction in Body Dysmorphic Disorder (BDD) which may be related to Obsessive-Compulsive Disorder (OCD). However, neurocognitive performance in the two disorders has rarely been compared. This study compared 14 BDD participants on neurocognitive tasks taken from the Cambridge Automated Neuropsychological Test Automated Battery (CANTAB) with previously published data from 23 OCD participants (Purcell, Maruff, Kyrios, & Pantelis, 1998). Effect sizes from three executive function tests (Spatial Span, Spatial Working Memory and Stockings of Cambridge), and one visual memory task (Pattern Recognition) were compared for group differences using difference and equivalence testing. Equivalence testing was used to determine whether BDD and OCD effects sizes were equivalent, non-equivalent or equivocal. Results indicated an equivocal pattern for Spatial Span, Spatial Working Memory, Pattern Recognition and most Stockings of Cambridge measures. However, results for Stockings of Cambridge accuracy measure indicated a non-equivalent pattern, with BDD but not OCD participants performing significantly worse than controls. Results suggest a number of similarities in neurocognitive function in BDD and OCD, although it was not possible to establish statistical equivalence on most study measures. The findings raise the possibility of more severe planning deficits in BDD compared to OCD.

The ability to regulate emotions is central to well-being, but healthy emotion regulation may not merely be about using the "right" strategies. According to the strategy-situation-fit hypothesis, emotion-regulation strategies are conducive to well-being only when used in appropriate contexts. This study is the first to test the strategy-situation-fit hypothesis using ecological momentary assessment of cognitive reappraisal-a putatively adaptive strategy. We expected people who used reappraisal more in uncontrollable situations and less in controllable situations to have greater well-being than people with the opposite pattern of reappraisal use. Healthy participants ( n = 74) completed measures of well-being in the lab and used a smartphone app to report their use of reappraisal and perceived controllability of their environment 10 times a day for 1 week. Results supported the strategy-situation-fit hypothesis. Participants with relatively high well-being used reappraisal more in situations they perceived as lower in controllability and less in situations they perceived as higher in controllability. In contrast, we found little evidence for an association between greater well-being and greater mean use of reappraisal across situations.

Patients with generalized social anxiety disorder (GSAD) exhibit heightened activation of the amygdala in response to social cues conveying threat (eg, fearful/angry faces). The neuropeptide oxytocin (OXT) decreases anxiety and stress, facilitates social encounters, and attenuates amygdala reactivity to threatening faces in healthy subjects. The goal of this study was to examine the effects of OXT on fear-related amygdala reactivity in GSAD and matched healthy control (CON) subjects. In a functional magnetic resonance imaging study utilizing a double-blind placebo-controlled within-subjects design, we measured amygdala activation to an emotional face matching task of fearful, angry, and happy faces following acute intranasal administration of OXT (24 IU or 40.32 μg) and placebo in 18 GSAD and 18 CON subjects. Both the CON and GSAD groups activated bilateral amygdala to all emotional faces during placebo, with the GSAD group exhibiting hyperactivity specifically to fearful faces in bilateral amygdala compared with the CON group. OXT had no effect on amygdala activity to emotional faces in the CON group, but attenuated the heightened amygdala reactivity to fearful faces in the GSAD group, such that the hyperactivity observed during the placebo session was no longer evident following OXT (ie, normalization). These findings suggest that OXT has a specific effect on fear-related amygdala activity, particularly when the amygdala is hyperactive, such as in GSAD, thereby providing a brain-based mechanism of the impact of OXT in modulating the exaggerated processing of social signals of threat in patients with pathological anxiety.