Biological Psychology

Humans make emotional facial expressions and have a cardiac response when they catch themselves in a mistake or receive feedback about task performance. We tested whether rats exhibit similar visceral responses in the context of metacognition. We assessed heart rate variability (HRV) and machine learning-detected facial expressions as female and male rats detected and stopped in-progress mistakes and received post-choice rewards or error cues. HRV increased during internally detected mistakes, as well as in response to external error cues for both sexes. Errors were associated with an HRV response when parasympathetic tone was higher, while rewards were associated with an HRV response when sympathetic tone was higher. We observed sex-specific effects of cardiac interoception on cognitive control over real-time action correction, in that low parasympathetic tone was associated with reduced ability to stop in-progress mistakes exclusively in females. Rats made facial expressions during mistake detection and in response to task feedback. Outcome-related facial expressions were valence-specific, in that the facial expression after error feedback was delayed relative to the post-reward facial expression. Our results suggest that rats have a visceral experience during metacognitive monitoring.

Learning in adulthood is embedded in everyday social life, in which periods of psychosocial stress alternate with recovery. The autonomic nervous system regulates how the body responds to environmental demands, yet individuals differ markedly in this regulation. It remains unknown whether such individual differences in bodily regulation modulate the ability to learn probabilistic patterns from sensory input. Here, we investigated statistical learning of probabilistic patterns in speech streams in a six-hour experiment incorporating psychosocial stress and recovery to approximate everyday conditions. Sixty-five adults were exposed to novel speech streams in high- and low-stress contexts, with learning assessed immediately after exposure and following a rest period. Heart rate variability was recorded throughout the experiment to capture individual differences in autonomic reactivity to stress and recovery. From these measures, we constructed composite proxies of sympathetic (SNS) and parasympathetic (PNS) nervous system reactivity. Individuals with congruent SNS-PNS reactivity--either jointly high or jointly low--showed superior statistical learning outcomes across stress contexts. SNS reactivity preferentially supported encoding, whereas PNS reactivity supported consolidation. Moreover, the effect of SNS activation during speech exposure on statistical learning depended on individuals SNS reactivity profiles. These findings demonstrate that individual differences in bodily regulation are tightly linked to the ability to learn statistical dependencies in stressful environments. Overall, the findings highlight the essential role of brain-body-environment interactions in statistical learning.

Ostracism (i.e., social exclusion) threatens social security and individuals who are hypersensitive to it may face long-term negative mental health consequences. Clarifying how self-reported distress and neural responses to ostracism unfold moment-by-moment and across varying levels of individual traits may help better understand what contributes to hypersensitivity. To this objective, the current study employed a functional near-infrared spectroscopy (fNIRS) adapted Cyberball task and single-trial analytic techniques in a sample of 53 college students (aged 18-22 years). Results confirmed that Cyberball induced ostracism increased self-reported distress and neural activity in the ventrolateral prefrontal cortex (vlPFC), a region associated with emotion regulation. Self-reported distress varied with differences in social anxiety and need for belonging. Moreover, vlPFC activity sensitized across exclusion-specific trials and this neural sensitization was differentially modulated by social anxiety, need for belonging, and personality growth mindset. The current study highlights the value of single-trial approaches for capturing the nuanced temporal dynamics of ostracism responses. Additionally, it underscores the importance of examining how individual differences shape immediate responses to ostracism to better understand their association with downstream, longer-term consequences.

Summary paragraphA hallmark of learning is the need for sensory stimuli (Ginns, 2015; McGraw et al., 2009; Reinwein, 2012; Spence, 1950) so that learning is fundamentally based on sensory input signals affecting behaviour, physiology, and neurology. If behavioural measures of learning can be causally linked to physiological and neurological variables, a broader understanding of the mechanisms related to learning in schools, learning disabilities, and learning and health issues may emerge (McGraw et al., 2009). Despite decades of research on the physiological/neurological variable of sympathetic activation, learning, and achievement (Horvers et al., 2021), any causal relation remains unclear (Cowley et al., 2014; Mason et al., 2020; Pijeira-Diaz et al., 2016; Sung et al., 2023; Yu et al., 2024) and issues with instrument validation remain (Costantini et al., 2023; Hu et al., 2024; Milstein & Gordon, 2020; Van Der Mee et al., 2021). Here we investigate the effect of sensory input on sympathetic activation by using validated instruments for skin conductance measurement (Batista et al., 2019) and whether sympathetic activation is connected to learning in a cognitive laboratory context and an ecologically valid classroom context. In both contexts, we found a physiological variable which correlated with learning and that sensory input affected this variable while student movement did not. These sensory inputs varied depending on the different instructional activities the students participated in. Together, these findings bring us one step closer to a model linking sensory input to behavioural, physiological, and neurological variables.

Empathy enables individuals to attune to others' experiences through shared affective, sensorimotor, and neural representations, but its influence on higher-level decision-making and social alignment remains unknown. We examined whether empathy promotes social conformity and whether this effect depends on physiological arousal, visual attention, and socio-emotional traits. Seventy-three participants completed an empathy-for-pain task followed by a modified random-dot task in which they interacted with previously seen empathy targets, while physiological signals and eye movements were recorded. Drift-diffusion modeling showed that feedback from empathy targets increased conformity, reflected in stronger decision bias toward targets, faster evidence accumulation, and reduced decision conservatism. Visual attention to the eyes or mouth was linked to greater conformity depending on the context. Heart rate variability was unrelated to conformity, whereas phasic skin conductance was associated with smaller bias changes and greater conservatism. Alexithymia and autistic traits further shaped the empathy-conformity relationships. These findings suggest that empathic shared representation extends beyond affective resonance to influence social alignment in decision-making.

Impaired learning that both novel and previously dangerous stimuli are safe (safety and extinction learning, respectively) are long standing, robust, and heritable features of anxiety disorders, representing potential endophenotypes. The computational mechanisms underpinning them have demonstrated associations with anxiety severity in recent studies. We undertook a pre-registered replication in a tenfold larger independent sample of twins (n = 925). Extinction learning rates were associated with anxiety severity ({rho}replication = -0.14, BFr0 = 1189. 67) but safety learning rates were not. Conversely, although safety learning rates showed modest heritability (h2safety = 0.16), extinction learning rates were not heritable. Accordingly, we were unable to identify genetic overlap between anxiety and either learning rate. Although this suggests neither learning rate is an anxiety endophenotype, we confirmed a cognitive-behavioral mechanism underpinning a robust marker of anxiety severity. Furthermore, we demonstrated heritability of a computationally modelled learning parameter, a key step towards establishing its biological basis.

Anhedonia - the diminished capacity to experience or anticipate pleasure - is among the most common consequences of early-life unpredictability, yet how these co-occurring conditions jointly shape real-world decision-making remains unknown. Here, we use a sequential foraging-under-threat task to probe motivational conflict decisions in 357 individuals varying in early-life unpredictability and anhedonia symptoms. We find that unpredictability and anhedonia exert opposing influences on choice: unpredictability shifts behavior away from the survival-optimal policy in a sex-dependent manner, while anhedonia promotes adherence to it, partly through heightened sensitivity to unexpected threatening outcomes. A mediation analysis reveals that anhedonia partially buffers the deleterious effects of unpredictability on decision quality. These results demonstrate that co-occurring conditions can mask one anothers behavioral signatures and suggest that the heterogeneous expression of transdiagnostic constructs like anhedonia may reflect context-dependent adaptations to distinct underlying etiologies.

Cortisol, our stress hormone, exerts widespread influence on neural activity. However, its influence on the aperiodic component of the electroencephalography power spectrum remains to be investigated. Given individual differences in the capacity to cope with stress and adversity, it also remains unclear whether trait resilience moderates this relationship. Hence, the present study examined whether individual differences in trait resilience moderates the association between resting cortisol and aperiodic activity. Participants (N=145) completed various self-report questionnaires (e.g., trait resilience). Electroencephalography was recorded over a 20-minute baseline period, followed by salivary cortisol collection. The results revealed a significant moderating effect of trait resilience in the occipital scalp region. Specifically, higher cortisol concentration was associated with flatter 1/f slopes amongst individuals with low trait resilience, whereas this association was reversed amongst those with high trait resilience. Overall, our findings highlight the role of individual differences in trait resilience in shaping hypothalamic-pituitary-adrenal axis-related neural dynamics.

Individuals with autism spectrum disorder (ASD) often exhibit atypical auditory processing, yet it remains unclear whether and how the integration of simple acoustic features and contextual information is impacted in ASD. One real-world example of this integration is the auditory looming bias, the prioritized processing and perception of approaching auditory stimuli. We designed a paradigm that presents intensity-rising (looming) and intensity-falling (receding) auditory stimuli to 3-4-year-old children with ASD (n = 21), children with sensory processing concerns who do not have ASD (SPC; n = 16) and children with typical development (TD; n = 30). We recorded neural responses using electroencephalography (EEG) and found evidence of looming bias in the SPC and TD groups, as indexed by greater P1 peak amplitude during the looming than receding stimuli (TD: t(64) = 6.87, p < .001; SPC: t(64) = 4.07, p < .001). But this finding was not present in the ASD group (p = .194). Additionally, the ASD group showed reduced differentiation between looming and receding stimuli, as indicated by significantly lower Rise-Fall Difference Score (RFDS) in comparison to the TD group (Z = -3.00, padj = .008). These findings suggested altered context-dependent modulation of sensory input in ASD. Lay SummaryMany children with autism show differences in how they process sounds. Using sound patterns in which loudness gradually increased and decreased over time, like many real-world sounds, we found that children with autism showed less neural differentiation between increasing and decreasing sounds. This finding suggested that the brain may process changes in sound differently in autism, particularly in how it adjusts to sounds as they change over time, which could contribute to the sensory challenges many children with autism experience in daily life.

Early life adversity is associated with increased risk for psychopathology and shifts in life history (LH) strategies, but the psychological mechanisms underlying these associations remain unclear. Drawing on evolutionary-developmental theory, we examined whether short-term mindsets mediate associations between dimensions of childhood adversity and mental health and LH-related outcomes. In a UK-representative sample of 877 adults, we assessed threat, deprivation, and unpredictability, alongside internalizing and externalizing symptoms, borderline features, and a latent factor capturing reproductive versus somatic maintenance effort. Structural equation models showed that adversity predicted poorer mental health and faster LH strategies. Short-term mindsets, indexed by lower future orientation and higher affective impulsivity, mediated effects of adversity, particularly unpredictability. Further decomposition of unpredictability into short-timescale and long-timescale forms revealed dissociable effects, with short-timescale unpredictability primarily linked to psychopathology and long-timescale unpredictability to reproductive-oriented LH strategies.

When humans learn under conditions of uncertainty, they dynamically adjust how they prepare for and respond to feedback. In navigating uncertain environments, the brain minimizes error by continuously refining internal models via memory updating (MU). Feedback is critical for MU, and anticipatory neural mechanisms shape how feedback is processed, likely reflecting learned environmental certainty. However, the literature has largely focused on post-feedback activity, leaving pre-feedback certainty-related mechanisms less understood. The present study aims to address this gap by examining how certainty modulates anticipatory states, preceding feedback and subsequent MU. We examined oscillatory activity prior to performance feedback in a reanalysis of EEG data previously published by Hassall and colleagues (2023). Twenty-one participants (16 female, Mage = 25.81 years) predicted the strength of cartoon characters with varying predictability levels which were learned through exposure. Feedback on prediction accuracy was presented via an animated rising bar. Results revealed that theta power is modulated by accumulative feedback. Linear mixed-effects models revealed an interaction between predictability-related certainty and learning stage: in late learning, higher performance was associated with increased pre-feedback alpha and beta power for low-certainty trials, whereas in early learning, higher performance was associated with decreased beta power. These learning-related modulations in alpha and beta power suggest that initial learning is marked by adaptable exploratory processing. Subsequent learning exhibited increased alpha-mediated inhibition and beta-related anticipatory activity for lower certainty trials, indicative of dynamic strategy refinement and selective engagement of task-relevant information. These results demonstrate that certainty shapes preparatory oscillatory activity associated with MU.

Learning is typically understood as a process driven by prediction errors, when outcomes differ from expectations. Yet it remains unclear whether outcomes that perfectly match expectations are psychologically and computationally meaningful. Here, we tested whether zero prediction errors shape affect, belief updating, and neural feedback processing in human reinforcement learning. Participants repeatedly predicted rewards in environments varying in uncertainty, with a subset of trial outcomes manipulated to exactly match their predictions. Zero prediction errors produced the highest momentary happiness, and computational modeling showed that behavior was best explained by a model in which zero prediction errors induce a distinct latent belief state that guides subsequent updating, particularly under higher uncertainty and in individuals with greater intolerance of uncertainty. Outcome-locked EEG analyses further showed that zero prediction errors elicited distinct P3-like responses, with residual neural activity predicting attenuated updating after zero prediction errors but enhanced updating after standard prediction errors. These findings suggest that perfect predictions are not neutral, but informative events that actively shape affect, behavior, and neural feedback processing.

Previous research suggests that women and men may differ in moral decision-making involving instrumental harm. However, prior findings have yielded inconsistent explanations for these differences, suggesting effects of gender expression, empathy, action tendencies, and biological causes, such as differences in gonadal hormone levels. Yet, no data exists on the effects of endogenous estradiol and progesterone on moral decision-making, while the effects of testosterone are inconsistent. Our study aimed to close this research gap. A sample of 137 cis individuals (73 women, 64 men) completed a moral dilemma task based on the Consequences, Norms, Inaction (CNI) model either in the morning or evening. Relevant personality traits, including agreement with instrumental harm, impartial beneficence, empathy, and gender expression, were assessed via self-report. Blood samples were analyzed for estradiol, progesterone, testosterone, and cortisol. Contrary to prior literature, no behavioral differences between women and men were observed in moral decision-making. However, self-reported agreement with instrumental harm positively predicted sensitivity to consequences and negatively predicted adherence to moral norms in the whole sample. Estradiol concentration positively predicted sensitivity to consequences in the morning women group, and general inaction tendency in the morning men group. Overall, these findings highlight the joint influence of biological and personality factors on moral choices and hint towards subtle sex/gender differences.

Mindfulness-based interventions effectively reduce stress and anxiety, yet the neural mechanisms underlying contemplative practices and their optimal implementation parameters remain poorly understood. A critical barrier to real-world application is the absence of validated minimally invasive neural recording technologies. Here, we simultaneously recorded full-coverage scalp and around-ear EEG during a 2x2x2 factorial design manipulating (1) cognitive state (mental arithmetic stress vs. passive viewing), (2) recovery strategy (mindful breathing meditation vs. mind-wandering), and (3) sensory context (eyes open vs. eyes closed). Mental arithmetic robustly elevated subjective stress and modulated canonical oscillatory patterns: increased midline frontal theta power (3-7 Hz), suppressed posterior alpha power (10-12 Hz), and enhanced posterior beta and gamma power (25-48 Hz). All rest conditions reduced subjective stress following stress induction, with eyes-closed mindful breathing producing maximal reduction. Critically, mindful breathing differentially modulated temporal beta and gamma power in a context-dependent manner, with effects determined by prior cognitive state and eye position. Eyes-closed meditation maximally suppressed gamma power within 20 seconds following arithmetic stress, whereas eyes-open meditation alone was sufficient for gamma suppression following passive viewing. Around-ear electrodes detected these stress and meditation signatures with comparable fidelity to scalp recordings. These findings reveal that mindful breathing engages rapid, context-dependent neural regulation mechanisms and establish that wearable EEG can reliably capture these dynamics, enabling real-world stress monitoring and mindfulness guidance. Impact StatementMindfulness-based interventions reduce stress, yet their neural mechanisms and optimal implementation remain unclear, partly due to limited real-world neural measurement tools. Using simultaneous scalp and around-ear EEG, we show that mindful breathing rapidly and context-dependently regulates stress-related brain activity via changes in high-frequency EEG oscillations (i.e., gamma band activity), with effects shaped by prior cognitive state and eye condition. Importantly, around-ear EEG captured these neural signatures with fidelity comparable to scalp recordings, enabling wearable neurotechnology for real-world stress monitoring and personalized mindfulness guidance.

It has been shown that early-life adversity (ELA) shapes how individuals learn, remember, and make decisions, yet the precise computations altered by these experiences remain unclear. Here, we combine a structured foraging task with computational modeling to test a recently developed theory for how a particular kind of ELA, early-life unpredictability (ELU), specifically influences choice under uncertainty. Adult participants (N=297) performed a sequential foraging task requiring continuous trade-offs between exploiting depleting resources and exploring alternatives. Subsets also completed assessments of early-life unpredictability (QUIC) and for trauma symptoms arising from lifelong stressors (PCL). We fit participants behavior with a Bayesian learning-and-planning model in which uncertainty modulates the valuation of leaving a current resource patch. Critically, the subjective influence of local uncertainty was allowed to vary freely between participants. Consistent with theoretical proposals, computational model fits and mediation analyses revealed a robust indirect pathway: ELU predicted increased discounting in the face of uncertainty, which in turn predicted greater overharvesting. This pattern was consistent across environmental conditions, indicating that early-life unpredictability primarily influences behavior through a general influence on uncertainty processing. Importantly, although PCL scores were also correlated with uncertainty adaptation, these effects were fully accounted for by shared variance with ELU, offering a clear dissociation between developmental unpredictability and lifelong traumatic experience. Together, our results show that early-life unpredictability causes long-lasting changes in decision-making by amplifying the subjective experience of uncertainty.

Attention abilities, that are critical for most real-life cognitive task, can vary greatly across individuals. A plethora of behavioral and neural metric are commonly utilized to quantify attention; however, these often yield inconsistent and non-replicable results, raising questions as to which measures reliably account for and capture individual differences. To address this tension, here we employed a within-subject cross-paradigm design and quantified both behavioral and EEG-based neural measures associated with attention functioning, to test which measures converged across a gradient of artificial and ecological tasks. We found Inter-Subject Correlation (ISC), which quantifies the similarity in the pattern of neural response across individuals, captured consistent individual differences across both an artificial (Auditory Oddball) and ecological (Attention to Speech) task, with some correlation with performance. Moreover, we found that P300 neural responses to surprising events were qualitatively similar across artificial and ecological tasks, supporting their generalization across contexts. Interestingly, traditional cognitive-behavioral measures of attention - both from speeded response-time tasks and self-report of ADHD symptoms (ASRS) were not correlated with each other nor did they explain variance in neural metrics, nor were they explained by variation in general cognitive abilities (working memory or fluid intelligence). While these results demonstrate the shortcomings of many established measures of attention to generalize across contexts, they also point to the potential of neural measures, and specifically ISC, to serve as reliable indicators of individual differences and to bridge the gap between artificial and ecological studies of attention functioning.

Anxiety and depression are globally prevalent conditions associated with maladaptive decision making. However, whether affective symptoms primarily amplify threat avoidance or dampen motivational drive remains debated, and behavioural studies yield inconsistent findings. Here we show that both anxiety and depression impair the fundamental cognitive process of translating objective value into decision evidence. Across independent cohorts from the US and India, participants evaluated risky gambles while we assessed choice behaviour and the centroparietal positivity, an EEG marker of accumulating decision evidence. Prospect theory parameters, like risk and loss aversion, showed little association with symptom severity. Conversely, hierarchical drift-diffusion modelling revealed that higher symptom scores predicted attenuated value sensitivity during evidence accumulation, whereas decision caution remained intact. This reduction in value sensitivity suggests internalizing symptoms disrupt choice at the value-to-evidence interface, offering a unified mechanism underlying biased decision making in affective disorders.

Creative ideation involves a dynamic exchange between exploring new idea categories and exploiting familiar ones, reflecting optimal foraging principles. Although interoceptive signals, particularly cardiac activity, are associated with differences in attention and cognitive control, their role in explore-exploit dynamics during creative idea generation remains unknown. Recording both electroencephalography (EEG) and electrocardiography (ECG) data, we used convolution general linear models to examine cardiac-brain interactions underlying semantic exploration and exploitation during creative idea generation, in both spontaneous (self-selected) and directed (externally cued) conditions. Cardiac deceleration predicted ideation time: this relationship scaled nonlinearly during exploration (category switching), but linearly during exploitation (category persistence), in both conditions. Cardiac deceleration did not predict semantic distance (between response and cue word) or response accuracy during the directed condition, suggesting that heart rate slowing reflects cognitive effort allocation rather than ideational content. Cardiac phase systematically biased explore-exploit dynamics: spontaneous switching and accurate directed-switching were preferentially associated with diastolic phases and parieto-occipital alpha (8-12 Hz) desynchronization, whereas category persistence was associated with systolic phase timing and frontal theta (4-6 Hz) synchronization. The former activity was coupled to higher CD, as expected. However, the latter time-frequency activity was linked to responses timed to systole. These findings suggest that creative ideation unfolds through embodied cardiac-cortical coordination, whereby diastolic states are associated with flexible semantic exploration and alpha-related attentional dynamics, whereas systolic states are associated with exploitative persistence and theta-related control processes. This suggests interoceptive rhythms as temporal scaffolding that structures when and how ideas emerge, fundamentally expanding creativity neuroscience beyond purely cortical models.

Disordered eating attitudes exist on a continuum that extends well below clinical diagnostic thresholds, yet the cognitive correlates of this non-clinical variation remain incompletely understood. Previous research linking executive functioning to disordered eating in non-clinical samples has relied almost exclusively on self-report questionnaire measures of executive function, which show weak correspondence with performance-based assessments. This methodological reliance leaves open the question of how objective executive performance relates to eating behavior across the spectrum. The present study addressed this gap by examining the association between performance-based measures of executive function and disordered eating attitudes in a non-clinical sample of 243 university students via an online experiment, using a dimensional approach consistent with the Research Domain Criteria framework. Participants completed established neurocognitive tasks covering three executive function domains: working memory was assessed with Digit Span and an N-back task, inhibitory control with a Go/No-Go task, and cognitive flexibility with the Card Sorting Task. Disordered eating attitudes were indexed using the EAT-26 total score and its subscales. A notable correlation was identified between cognitive flexibility and disordered eating attitudes, while working memory and inhibitory control exhibited no such association. Overall, our findings provide evidence for associations between executive functioning and disordered eating attitudes in a non-clinical sample.

Singing is an innate human behaviour present across cultures and the lifespan. Despite lacking direct biological advantages, its ubiquity suggests that it is intrinsically rewarding. This research aimed to investigate the underlying factors that explain variability in sensitivity to deriving reward and enjoyment from natural singing in the general population. In Study 1 (n = 606), an initial pool of items describing daily, non-professional singing behaviours were administered to an international adult sample. Exploratory factor analysis revealed a unidimensional structure of 20 items with acceptable model fit, organized into five facets representing distinct domains of singing-related rewards: 1) pleasure and emotional evocation, 2) social singing reward, 3) singing frequency, 4) mood regulation through singing, and 5) inattentional singing during routine tasks. In Study 2 (n = 430), confirmatory factor analysis in a new sample supported this structure. When both samples were combined (n = 1036), the unidimensional model defined by these five facets showed acceptable to excellent goodness-of-fit indices, supporting the conceptualization of singing reward as a multidimensional construct with differentiated facets. This led to the Barcelona-Aarhus Natural Singing Engagement Questionnaire (BANSEQ), which demonstrated excellent reliability ( = .94) and population-level stability. Study 3 (n = 1036) tested the convergent validity of BANSEQ with measures of music reward and engagement and identified sociodemographic and psychological correlates across the five facets of singing reward. Overall, these findings characterize the sources of individual differences in the hedonic experience of natural singing and propose BANSEQ as a robust psychometric tool for its assessment in the general population.