Biology subjects

Roelofs, K.

Publications and source records attributed to Roelofs, K..

At least 19 recordsLinked to original sources

bioRxiv2026

Stretch-induced muscle responses under threat vs safety

When in a stressful situation, making fast and accurate decisions is crucial. Previous work has shown that sensorimotor decisions can improve under threat. However, it is unclear if these improvements are achieved by improvements in perceptual or motor performance. Here, we present two hypotheses for how threat might influence motor preparation and use muscular stretch reflexes to test both. The task-unspecific hypothesis predicts that threat promotes motor preparation irrespective of the reach target, through tonic upregulation of the short latency stretch reflex. In contrast, the task-specific hypothesis predicts that threat increases sensory processing for a specific reach target, leading to direction-selective up- and down-regulation of the long latency stretch reflex. Participants were asked to reach to one of two targets that appeared shortly before a perturbation eliciting a stretch reflex, they performed this task either under threat of an electric shock or under safe circumstances. Skin conductance and heart rate results show that the threat manipulation significantly increased sympathetic activation, but not parasympathetic activation. Supporting the task-specific hypothesis, the EMG findings demonstrate a direction-selective modulation of the long-latency response of stretch reflexes, starting ~100 ms after perturbation onset. Our results suggest that stress affects action preparation through upregulation of cortical visuomotor circuits.

physiology↗

bioRxiv2026

Testosterone Administration Modulates Competitive Choice via Ventral Striatum and TPJ

How does testosterone influence decisions and choice-related neural computations in competitive environments? To address this question, we administered testosterone or placebo to female participants (n = 54) in a double-blind, randomized design. Following drug treatment, participants competed in a dot estimation task that manipulated opponent status (lower, equal, or higher) and outcome feedback (win or loss), after which they decided whether to compete against the same opponent again. All participants adjusted their behavior based on opponent status and outcome feedback. Participants who received testosterone, however, showed significantly greater sensitivity to outcome feedback: they were more willing to compete after winning and less willing after losing, and made those decisions faster - suggesting that testosterone increases the weighting of immediate, salient outcome information in competitive decision-making. At the neural level, a network comprising ventral striatum, vmPFC, bilateral TPJ and ACC processed outcome-related signals during the feedback period. Critically, neural prediction analyses at the trial-level revealed that activity in left ventral striatum and TPJ predicted subsequent decisions to compete, but only in participants who received testosterone. The direction of these effects mirrored the behavioral results: striatal activity amplified the tendency to re-compete after winning, whereas TPJ activity predicted renewed competition after losing. Together, these findings demonstrate that testosterone biases competitive decisions by amplifying the influence of outcome-related activity in reward and social cognition circuits.

neuroscience↗

bioRxiv2025

Spine-brain dynamics during human defensive threat-reactions

Synchrony between central and autonomic nervous system responses during threat rely on spine-brain interactions. Activation of the parasympathetic autonomic nervous system during acute threat has been linked to optimized action preparation and longer-term stress-resilience. However, it is unclear how this is orchestrated by spine-brain interactions during our widely used models of threat conditioning. Here we used a well-established threat conditioning procedure to test whether freezing-related bradycardia modulates the strength of motor- and sensory-relevant spinal-brain connectivity patterns. Conditioning elicited the expected autonomic and psychophysiological responses, with significant bradycardia and heightened differentiation between conditioned stimuli. Heart rate bradycardia modulated activity in the cingulate cortex and spinal cord, emphasizing their role in freezing. Notably, bradycardia-modulated spinal cord activity during threat was functionally coupled with motor cortex activity, suggesting a preparatory response for defensive actions. Establishing these effects for the first time in humans helps discovery of biomarkers for threat coping-relevant body-brain interactions, essential for clinical evaluations.

neuroscience↗

bioRxiv2024

Defensive freezing sharpens threat-reward information processing during approach-avoidance decision making

People regularly face approach-avoidance dilemmas which require minimization of potential threat whilst maximizing potential reward. Defensive reactions to threat, such as transient states of freezing, influence integration of reward/threat information in the dorsal Anterior Cingulate Cortex (dACC). However, the mechanism of this integration between internal state and external value (state-value integration) remains unknown. Here, we decoded approach-avoidance decisions under threat using high-precision magnetoencephalography (MEG). Threat-induced cardiac deceleration (indicative of defensive freezing) was trial-by-trial associated with more pronounced effects of reward and threat magnitudes on approach-avoidance choices. Time-resolved decoding of threat-reward information from neural signals predicted approach-avoidance choices several seconds before the actual response. Crucially, during freezing, 6-12 Hz coherence between threat-reward information and dACC neural activity increased, suggesting that defensive freezing sharpens threat/reward processing during approach-avoidance decision making. These findings provide a potential neural mechanism by which threat-induced freezing can facilitate information integration, essential for optimal decision making under threat.

neuroscience↗

bioRxiv2024

How distributed subcortical integration of reward and threat may inform approach-avoidance decisions

Healthy and successful living involves carefully navigating rewarding and threatening situations by balancing approach and avoidance behaviours. Excessive avoidance to evade potential threats often leads to forfeiting potential rewards. However, little is known about how reward and threat information is integrated neurally to inform approach or avoidance decisions. In this preregistered study, participants (Nbehaviour=31, 17F; NMRI=28, 15F) made approach-avoidance decisions under varying reward (monetary gains) and threat (electrical stimulations) prospects during functional MRI scanning. In contrast to theorized parallel subcortical processing of reward and threat information before cortical integration, Bayesian Multivariate Multilevel analyses revealed subcortical reward and threat integration prior to indicating approach-avoidance decisions. This integration occurred in the ventral striatum, thalamus, and bed nucleus of the stria terminalis (BNST). When reward was low, risk-diminishing avoidance decisions dominated, which was linked to more positive tracking of threat magnitude prior to indicating avoidance than approach decisions across these regions. In contrast, the amygdala exhibited dual sensitivity to reward and threat. While anticipating outcomes of risky approach decisions, we observed positive tracking of threat magnitude within the salience network (dorsal anterior cingulate cortex, thalamus, periaqueductal gray, BNST). Conversely, after risk-diminishing avoidance, characterized by reduced reward prospects, we observed more negative tracking of reward magnitude in the ventromedial prefrontal cortex and ventral striatum. These findings shed light on the temporal dynamics of approach-avoidance decision-making. Importantly, they demonstrate the role of subcortical integration of reward and threat information in balancing approach and avoidance, challenging theories positing predominantly separate subcortical processing prior to cortical integration.

neuroscience↗

bioRxiv2024

Specific amygdala and hippocampal subfield volumes in social anxiety disorder and their relation to clinical characteristics; an international mega-analysis

Social anxiety disorder (SAD) has been associated with alterations in amygdala and hippocampal volume but there is mixed evidence for the direction of volumetric alterations. Additionally, little is known about the involvement of the distinct subfields in the pathophysiology of SAD. Volumetric data from a large multi-centre sample of 107 adult individuals with SAD and 140 healthy controls (HCs) was segmented using FreeSurfer to produce 9 amygdala and 12 hippocampal subfield volumes. Volumes were compared between groups using linear mixed-effects models adjusted for age, age-squared, sex, site and whole amygdala and hippocampal volumes. Subgroup analyses examined subfield volumes in relation to comorbid anxiety disorder, and comorbid major depressive disorder (MDD), psychotropic medication status, and symptom severity. In the full sample, SAD was associated with smaller amygdala volumes in the basal (d=-0.32, pFDR=0.022), accessory basal (d=- 0.42, pFDR=0.005) and corticoamygdaloid transition area (d=-0.37, pFDR=0.014), and larger hippocampal volume in the CA3 (d=0.34, pFDR=0.024), CA4 (d=0.44, pFDR=0.007), dentate gyrus (d=0.35, pFDR=0.022) and molecular layer (d=0.28, pFDR= 0.033), compared to HCs. SAD without comorbid anxiety, in addition, demonstrated smaller lateral amygdala (d=-0.30, pFDR=0.037) and hippocampal amygdala transition area (d=-0.33, pFDR=0.027) relative to HCs. In SAD without comorbid MDD, only the smaller accessory basal amygdala remained significant (d=-0.41, pFDR=0.017). No association was found between subfield volume and medication status or symptom severity. In conclusion, we observed distinct patterns of volumetric differences across specific amygdala and hippocampal subfields, regions that are associated with sensory information processing, threat evaluation and fear generalization. These findings suggest a possible disruption in information flow between the amygdala and hippocampal formation for fear processing in SAD.

neuroscience↗

bioRxiv2023

The neurocomputational link between defensive cardiac states and approach-avoidance arbitration under threat

Fearful avoidance is a hallmark of anxiety disorders and often comes at a cost. It reduces the probability of threat and of obtaining rewards. Theoretical models predict that threat-induced psychophysiological states, such as freezing-related bradycardia, facilitate arbitration of approach-avoidance decisions. We indeed show that bradycardia states are linked to the neurocomputational underpinnings of approach-avoidance arbitration when facing varying reward and threat magnitudes. Bradycardia was not only linked to aversive value-related avoidance decisions but also to value comparison (a stronger tendency to approach vs. avoid when expected reward outweighs potential threat). An amygdala-striatal-prefrontal neural circuit supported approach-avoidance arbitration under threat, with specific involvement of the amygdala and dorsal anterior cingulate (dACC) in integrating subjective outcome values and bradycardia states. These findings highlight the role of human freezing states in value-based decision making, relevant for optimal threat coping. They point to a specific role for amygdala/dACC in state-value integration under threat.

neuroscience↗

bioRxiv2023

Improving approach-avoidance control in social anxiety by targeting phase-amplitude coupling between prefrontal and sensorimotor cortex

Social avoidance is a hallmark of social anxiety disorder. Difficulties in controlling avoidance behavior are the core maintaining factor of this impairing condition, hampering the efficacy of existing therapies. This preregistered study tested a physiologically-grounded non-invasive enhancement of control over social approach and avoidance behavior in socially anxious individuals. Their prefrontal and sensorimotor areas received dual-site phase-coupled electrical stimulation, to enhance endogenous inter-regional theta-gamma phase-amplitude coupling, a mechanism known to support emotion control in non-anxious individuals. We measured behavioral and fMRI-BOLD responses during in-phase, anti-phase, and sham stimulations, while participants performed a social approach-avoidance task, involving either automatic or controlled emotional actions. In-phase stimulation selectively enhanced control over approach-avoidance actions, and modulated neural responses in the same prefrontal region where stimulation-reactivity increased as a function of trait anxiety. These findings illustrate how human neurophysiological connectivity can be leveraged to improve control over social avoidance, opening the way for mechanistically grounded clinical interventions of persistent avoidance in anxiety disorders. SIGNIFICANCE STATEMENTControlling automatic approach-avoid behavior is essential for human social interactions. This ability is impaired in social anxiety, but we know how neurotypical brains use endogenous rhythmic coupling for social emotion control. In a preregistered study, we used noninvasive electrical brain stimulation to enhance endogenous rhythmic coupling between prefrontal theta- and sensorimotor gamma-band rhythms, while highly socially anxious individuals solved an emotional control challenge. In-phase stimulation selectively enhanced emotional action control and modulated neural activity in a prefrontal cortex region where brain stimulation reactivity increased as a function of trait anxiety. These findings provide evidence for the generalizability and clinical potential of this interventional approach to social anxiety.

neuroscience↗

bioRxiv2023

No evidence for a link between childhood (6-10y) cellular aging and brain morphology (12y) in a preregistered longitudinal study.

Animal studies show that early life environmental factors, such as stress and trauma, can have a significant impact on a variety of bodily processes, including cellular aging and brain development. However, whether cellular wear-and-tear effects are also associated with individual differences in brain structures in humans, remains unknown. In this pre-registered study in a community sample of children (N=94, Mean age=12.71 years), we prospectively investigated the predictive value of two markers of cellular aging in childhood (at age 6 and 10) for brain morphology in early adolescence (age 12). More specifically, we associated buccal cell telomere length and epigenetic age in childhood to individual differences in adolescent whole-brain grey matter volume (GMV) including volumes of three regions of interest that have been found to be sensitive to effects of early life stress (i.e. amygdala, hippocampus, (pre)frontal cortex -PFC). Multiple regression analyses revealed no significant associations between childhood cellular aging (at 6 and 10 years) and early adolescent brain morphology. Exploratory Bayesian analyses indicated moderate to strong evidence for the null-findings. These results suggest that although our sample is modest, the associations between middle childhood cellular aging and early adolescent brain morphology are, if they do exist, likely not particularly large in community children. Future work should investigate whether these effects are similarly absent in large samples, in samples with a higher risk profile and in samples characterized by different age ranges. Highlights (3-5)- Investigation of cellular aging in relation to brain morphology in a community sample (N=95) - Epigenetic aging and telomere shortening were not associated with brain structure - Exploratory Bayesian Analyses reveal moderate to strong evidence for null findings - No association was found between cellular aging and white matter volume

neuroscience↗

bioRxiv2023

The relevance of accounting for parasympathetic as well as sympathetic arousal in threat conditioning: methodological and clinical considerations

Alterations in associative threat learning have been thought to underlie the aetiology and maintenance of anxiety disorders. Recent insights into the facilitatory role of parasympathetic arousal for threat coping have raised the question whether individual differences in parasympathetic versus sympathetic dominance during threat learning may explain the unstable relationship with anxiety vulnerability versus resilience. We applied an established threat-conditioning paradigm in 78 neurotypical individuals and assessed parasympathetic responses (relative bradycardia), as well as sympathetic response patterns (relative tachycardia and increased skin conductance responses -SCR). We observed threat-induced bradycardia as well as tachycardia during associative learning. Additionally, participants not showing conditioned SCR still exhibit significant conditioned threat responses expressed in parasympathetically driven threat bradycardia. Critically, tachycardia, rather than bradycardia, was linked to stronger initial conditioned SCRs and higher trait anxiety. These results suggest individual differences in sympathetic versus parasympathetic dominance may underlie anxiety vulnerability versus resilience. Statement of relevanceOur findings underscore the relevance of assessing the whole spectrum of autonomic nervous system responses to threat. By assessing sympathetic and parasympathetic threat responses, we demonstrate associations with anxiety vulnerability, which could not be unveiled by assessing sympathetic arousal alone. Since alterations in associative threat learning are thought to underlie anxiety-related psychopathology, it is of clinical and methodological relevance to assess threat responses with measures that are sensitive to both parasympathetic and sympathetic arousal. Additionally, we show that individuals that lack sympathetically-driven conditioned SCRs -- often classified as non-learners -- in fact do show a parasympathetically-driven HR threat response (bradycardia). Critically, bradycardia was linked to lower trait anxiety. These results imply a paradigm shift in the field of threat learning, shifting the predominant focus on sympathetic arousal towards the balance between sympathetic and parasympathetic arousal. This could advance insights in the role of threat learning in anxiety vulnerability and resilience.

physiology↗

bioRxiv2023

Integrating stereotypes and factual evidence in interpersonal communication

Stereotypes can exert a powerful influence on our interactions with others, potentially leading to prejudice when factual evidence is ignored. Here, we identify neuroanatomical and developmental factors that influence the real-time integration of stereotypes and factual evidence during live social interactions. The study uses precisely quantified communicative exchanges in a longitudinal cohort of seventeen-year-olds followed since infancy, testing their ability to moderate stereotype tendencies toward children as contrary evidence accumulates. Our results indicate that the impact of stereotypes on communicative behavior is linked to individual variations in gray matter density and cortical thickness in the right anterior cingulate gyrus. In contrast, the ability to moderate stereotype tendencies is influenced by developmental exposure to social interactions during the initial years of life, beyond the effects of familial environment and later experiences. These findings pinpoint a key brain structure underlying stereotype tendencies and suggest that early-life social experiences have lasting consequences on how individuals integrate factual evidence in interpersonal communication.

neuroscience↗

bioRxiv2022

Developmental shift in testosterone influence on prefrontal emotion control

A paradox of testosterone effects is seen in adolescents vs. adults in social emotional approach-avoidance behavior. During adolescence, high testosterone levels are associated with increased anterior prefrontal (aPFC) involvement in emotion control, whereas during adulthood this neuro-endocrine relation is reversed. Rodent work shows that, during puberty, testosterone transitions from a neuro-developmental to a social-sexual activating hormone. In this study, we explored whether this functional transition is also present in human adolescents and young adults. Using a prospective longitudinal design, we investigated the role of testosterone on neural control of social emotional behavior during the transitions from middle to late adolescence and into young adulthood. Seventy-one individuals (tested at ages 14, 17, and 20 years) performed an fMRI-adapted approach-avoidance (AA) task involving automatic and controlled actions in response to social emotional stimuli. In line with predictions from animal models, the effect of testosterone on aPFC engagement decreased between middle and late adolescence, and shifted into an activational role by young adulthood - impeding neural control of emotions. This change in testosterone function was accompanied by increased testosterone-modulated amygdala reactivity. These findings qualify the testosterone-dependent maturation of the prefrontal-amygdala circuit supporting emotion control during the transition from middle adolescence into young adulthood.

neuroscience↗

bioRxiv2022

Predicting Math Ability using Working Memory, Number Sense, and Neurophysiology in Children and Adults

Previous work has shown relations between domain-general processes, domain-specific processes, and mathematical ability. However, the underlying neurophysiological effects of mathematical ability are less clear. Recent evidence highlighted the potential role of beta oscillations in mathematical ability. Here we investigate whether domain-general (working memory) and domain-specific (number sense) mediate the relation between resting-state beta oscillations and mathematical ability, and how this may differ as a function of development (children vs. adults). We compared a traditional analysis method normally used in EEG studies with a more recently developed parameterization method that separates periodic from aperiodic activity. Regardless of methods chosen, we found no support for mediation of working memory and number sense, neither for children nor for adults. However, we found subtle differences between the methods. Additionally, we showed that the traditional EEG analysis method conflates periodic activity with aperiodic activity, and the latter is strongly related to mathematical ability and this relation differs between children and adults. At the cognitive level, our findings do not support previous suggestions of a mediation of working memory and number sense. At the neurophysiological level our findings suggest that aperiodic, rather than periodic, activity is linked to mathematical ability as a function of development.

neuroscience↗

bioRxiv2021

Defensive freezing and its relation to approach-avoidance decision-making under threat

Successful responding to acutely threatening situations requires adequate approach-avoidance decisions. However, it is unclear how threat-induced states-like freezing-related bradycardia-impact the weighing of the potential outcomes of such value-based decisions. Insight into the underlying computations is essential, not only to improve our models of decision-making but also to improve interventions for maladaptive decisions, for instance in anxiety patients and first-responders who frequently have to make decisions under acute threat. Forty-two participants made passive and active approach-avoidance decisions under threat-of-shock when confronted with mixed outcome-prospects (i.e., varying money and shock amounts). Choice behavior was best predicted by a model including individual action-tendencies and bradycardia, beyond the subjective value of the outcome. Moreover, threat-related bradycardia interacted with subjective value, depending on the action-context (i.e., passive vs. active). Specifically, in action-contexts incongruent with participants intrinsic action-tendencies, strong freezers showed diminished effects of subjective value on choice. These findings illustrate the relevance of testing approach-avoidance decisions in relatively ecologically valid conditions of acute and primarily reinforced threat. These mechanistic insights into approach-avoidance conflict-resolution may inspire biofeedback-related techniques to optimize decision-making under threat. Critically, the findings demonstrate the relevance of incorporating internal psychophysiological states and external action-contexts into models of approach-avoidance decision-making.

neuroscience↗

bioRxiv2020

Orbitofrontal lesion patients show an implicit approach bias to angry faces

Damage to the ventromedial prefrontal cortex (VMPFC) can cause maladaptive social behavior, but the cognitive processes underlying these behavioral changes are still uncertain. Here, we tested whether patients with acquired VMPFC lesions show altered approach-avoidance tendencies to emotional facial expressions. Thirteen patients with focal VMPFC lesions and 31 age- and gender-matched healthy controls performed an implicit approach-avoidance task in which they either pushed or pulled a joystick depending on stimulus color. While controls avoided angry faces, VMPFC patients displayed an incongruent response pattern characterized by both increased approach and reduced avoidance of angry facial expressions. The approach bias was stronger in patients with higher self-reported impulsivity and disinhibition, and in those with larger lesions. We further used linear ballistic accumulator modelling to investigate latent parameters underlying approach-avoidance decisions. Controls displayed negative drift rates when approaching angry faces, whereas VMPFC lesions abolished this pattern. In addition, VMPFC patients had weaker response drifts than controls during avoidance. Finally, patients showed reduced drift rate variability and shorter non-decision times, indicating impulsive and rigid decision-making. Our findings thus suggest that VMPFC damage alters the pace of evidence accumulation in response to social signals, eliminating a default, protective avoidant bias and facilitating dysfunctional approach behavior.

neuroscience↗

bioRxiv2020

Improving emotional-action control by targeting long-range phase-amplitude neuronal coupling.

Control over emotional action tendencies is essential for every-day interactions. This cognitive function can fail during socially challenging situations, and is chronically attenuated in social psychopathologies such as social anxiety and aggression. Previous studies have shown that control over social-emotional action tendencies depends on phase-amplitude coupling between prefrontal theta-band (6 Hz) rhythmic activity and broadband gamma-band activity in sensorimotor areas. Here, we delivered dual-site phase-coupled brain stimulation to facilitate theta-gamma phase-amplitude coupling between frontal regions known to implement that form of control, while participants were challenged to control their automatic action tendencies in a social-emotional approach/avoidance-task. Participants had increased control over their emotional action tendencies, depending on the relative phase and dose of the intervention. Concurrently measured fMRI effects of task and stimulation, and estimated changes in effective connectivity, indicated that the intervention improved control by increasing the efficacy of anterior prefrontal inhibition over sensorimotor cortex. This enhancement of emotional action control provides causal evidence for a phase-amplitude coupling mechanism guiding action selection during emotional-action control. More generally, the finding illustrates the potential of physiologically-grounded interventions aimed at reducing neural noise in cerebral circuits where communication relies on phase-amplitude coupling.

neuroscience↗

bioRxiv2019

Human lateral Frontal Pole contributes to control over social-emotional behaviour

Regulation of emotional behavior is essential for human social interactions. Recent work has exposed its cognitive complexity, as well as its unexpected reliance on portions of the anterior prefrontal cortex (aPFC) also involved in exploration, relational reasoning, and counterfactual choice, rather than on dorsolateral and medial prefrontal areas involved in several forms of cognitive control. This study anatomically qualifies the contribution of aPFC territories to the regulation of social-emotional actions, and explores a possible structural pathway through which emotional regulation might be implemented. We provide converging evidence from task-based fMRI, diffusion-weighted imaging, and functional connectivity fingerprints for a novel neural element in emotional regulation. Task-based fMRI in human male participants (N = 40) performing a social-emotional approach-avoidance task identified aPFC territories involved in the regulation of social-emotional actions. Connectivity fingerprints, based on diffusion-weighted imaging and resting-state connectivity, localized those task-defined frontal regions to the lateral frontal pole (FPl), an anatomically-defined portion of the aPFC that lacks a homologous counterpart in macaque brains. Probabilistic tractography indicated that 10-20% of inter-individual variation in social-emotional regulation abilities is accounted for by the strength of structural connectivity between FPl and amygdala. Evidence from an independent replication sample (N = 50; 10 females) further substantiated this result. These findings provide novel neuroanatomical evidence for incorporating FPl in models of control over human social-emotional behavior. Significance statementSuccessful regulation of emotional behaviors is a prerequisite for successful participation in human society, as is evidenced by the social isolation and loss of occupational opportunities often encountered by people suffering from emotion-regulation disorders such as social-anxiety disorder and psychopathy. Knowledge about the precise cortical regions and connections supporting this control is crucial for understanding both the nature of computations needed to successfully traverse the space of possible actions in social situations, and the potential interventions that might result in efficient treatment of social-emotional disorders. This study provides evidence for a precise cortical region (FPl) and a structural pathway (the ventral amygdalofugal bundle) through which a cognitively complex form of emotional action regulation might be implemented in the human brain.

neuroscience↗

bioRxiv2019

Human defensive freezing is associated with acute threat coping, long term hair cortisol levels and trait anxiety.

The detection and anticipation of threat facilitates innate defensive behaviours including freezing reactions. Freezing in humans is characterized by reductions in body sway and heart rate and limited evidence suggests that individual differences in freezing reactions are associated with hypothalamic-pituitary-adrenal (HPA) axis activity and anxiety. However, previous measurements of human freezing reactions were largely based on passive threat contexts where natural variations in adaptive threat coping could not be assessed. In a well powered sample (N=419), we studied individual differences in anticipatory freezing reactions, by measuring body sway and heart rate, during an active shooting task where shooting decisions had to be taken under threat of shock. We linked freezing measures to subsequent actions and predictors of anxiety-related psychopathology, including accumulated long-term (3 months) hair cortisol concentrations (HCC) and trait anxiety. The anticipation of threat of shock elicited significant body sway- and heart rate reductions consistent with freezing. Whereas both freezing-related reductions in body sway and heart rate were associated with faster correct shooting decisions, body sway reductions were additionally related to more impulsive shooting (false alarms). Individual differences in threat-related reductions in body sway but not heart rate were further associated to lower HCC and higher trait anxiety. The observed links between freezing and subsequent defensive actions as well as predictors of stress-related psychopathology suggest the potential value of defensive freezing reactions as somatic marker for stress-vulnerability and resilience.

physiology↗