Manipulating Levels of Socially Evaluative Threat and the Impact on Anticipatory Stress Reactivity

The relationship between cardiorespiratory fitness and inhibitory control following acute stress: An ERP study

Although the relationships among acute stress, cardiorespiratory fitness (CRF), and cognitive function have been examined, whether CRF is related to behavioral and neuroelectric indices of inhibitory control following acute stress remains unknown. The purpose of the current study was to investigate the combined influence of acute stress and CRF on inhibitory control. Participants, aged 20-30 years, were stratified into the Higher-Fit (n = 31) and the Lower-Fit (n = 32) groups, and completed a Stroop task following the modified Maastricht Acute Stress Test (MAST) in the stress condition and the sham-MAST in the non-stress condition, during which electroencephalography was recorded. Behavioral (i.e., response time and accuracy) and neuroelectric (N2 and P3b components of the event-related potential) outcomes of inhibitory control were obtained. While the Higher-Fit group demonstrated shorter response times and higher accuracy than the Lower-Fit group following both the MAST and the sham-MAST, they also exhibited selective benefits of acute stress on inhibitory control performance (i.e., decreased response times and diminished interference scores). CRF-dependent alterations in neuroelectric indices were also observed, with the Higher-Fit group displaying smaller N2 and greater P3b amplitudes than the Lower-Fit group following the sham-MAST, and increased N2 and attenuated P3b amplitudes following the MAST. Collectively, these findings not only confirm the positive relationship between CRF and inhibitory control but also provide novel insights into the potential influence of CRF on inhibitory control and associated neuroelectric activity following acute stress.

The effect of socially evaluated multitasking stress on typing rhythms

Individuals have unique typing rhythms characterized by specific keystroke dynamics. Changes in state and cardiovascular responding are well documented manifestations of the fight-flight response to stress. However, as stress also leads to changes in muscle tone and motor control, typing rhythms may also be impacted. We aim to determine which individuals are experiencing stress through their typing rhythms and identify universal keystroke markers of stress. Participants (N = 116) typed 80 repetitions of a 6-word, 30-character phrase before and after 15 min of critically evaluated multitasking stress. Cardiovascular, hemodynamic, and state variables were compared across baseline, stress, and recovery periods and measures of typing rhythm were derived for each period and classified using machine-learning algorithms. Critically evaluated multitasking led to significant changes in all stress measures, demonstrating highly robust stress reactivity. Machine learning algorithms accurately classified stressed typing for each individual based on their typing rhythms; however, no universal keystroke markers of stress were identified. Using typing rhythms. We were able to determine whether an individual was stressed or not, but the markers used for classification differed between individuals. These individual changes may provide opportunities for identifying stressful periods through keystroke monitoring, as well as the potential for early identification of disorders which may impact fine motor control. Typing rhythms could therefore be used to monitor health and well-being in individuals who use keyboards in various situations. This is the first rigorous assessment of stress and typing rhythms and has led to the development of a feasible and highly reproducible research protocol.

Kindhearted: Ethical guilt and ethical heart rate reactivity codevelop with aggression across childhood

Largely cross-sectional evidence indicates that ethical guilt is a robust predictor of childhood aggression. However, the underlying mechanisms of ethical guilt-in part assessed as ethical heart rate (HR) reactivity in the present study-are less clear, and longitudinal associations between ethical guilt, its underlying mechanisms, and aggression have not been explored. The present study used a multicohort longitudinal design to assess these constructs across early and middle childhood. At the beginning of the study and 2 years later, cohorts of 4- and 8-year-olds (ns = 150; N = 300) reported their guilt in response to an ethical transgression (i.e., pushing) and a nonethical transgression (i.e., breaking a classroom rule), and their HR was measured while they imagined committing these acts. Caregivers reported their child's aggression at each time point via questionnaire. Latent difference score models indicated that, regardless of cohort, children who increased in their ability to prioritize ethical guilt over 2 years were more likely to decrease in aggression over the same period. Moreover, children whose HR reactivity became more sensitive to ethical transgressions over time showed corresponding declines in aggression over time. Overall, these findings highlight the potential protective roles of children's capacities to react affectively and autonomically to the gravity of ethical transgressions across early and middle childhood.