Vagal Flexibility Mediates the Association Between Resting Vagal Activity and Cognitive Performance Stability Across Varying Socioemotional Demands

The Association of Physical Activity and Stress-induced Neurocognitive Impairments in Inhibitory Control in Children

Background

Evaluation stress can impair inhibitory control, limiting the ability of children to perform cognitively. However, evidence on protective factors is lacking as stress-induced cognitive impairments are poorly understood. High physical activity has been related to better inhibitory control and has the potential to buffer the response to a stressor. We investigated the association of physical activity and stress-induced changes in inhibitory control as well as its underlying cognitive control processes (i.e., conflict monitoring and resolution).

Method

Participants (10 to 13 y) with either low (N = 55) or high moderate-to-vigorous physical activity (N = 55) completed the Trier Social Stress Test for Children (TSST-C) and a control task in a randomized order. During both conditions, salivary cortisol was collected. Additionally, a computerized Stroop task was administered before and after the experimental conditions. The N200 and positive slow wave (PSW) components of event-related potentials elicited by the Stroop task were recorded using electroencephalography.

Results

In comparison to the control task, the TSST-C elicited a pre-to post-test decrease of accuracy on incompatible trials. Path-analyses further revealed that this decrease was related to low physical activity and a reduced PSW amplitude. However, both the N200 and PSW amplitudes did not mediate the relation between physical activity groups and performance on the Stroop task.

Conclusion

In children, evaluation stress decreases inhibitory control partly due to a reduced effectiveness of conflict resolution processes. Only children with high physical activity maintain inhibitory control after facing the stressor. However, this protective effect cannot be attributed to changes in conflict monitoring and resolution.

Exploring the efficacy of sense of Okayness (SOK) as an antidote for stress in older adults: the role of SOK elevation intervention, heart rate variability (HRV), and cognitive performance in stressful and relaxing situations

Sense of Okayness (SOK) is an emerging concept that describes a person's ability to remain stable and unshaken in the face of life transitions and hardships. This quality enables effective stress regulation and heightened tolerance to uncertainty. To investigate the possible role of the parasympathetic nervous system (PNS) in mediating the relationship between SOK and stress regulation among older individuals, an analytical sample of N  =  69 participants (74% women) with a mean age of 78.75 years (SD age  =  6.78) was recruited for a standardized cognitive assessment and stress induction. Baseline heart rate variability (HRV), measured via electrocardiogram (ECG), and SOK assessments were conducted prior to stress induction, along with a baseline cognitive evaluation. Subsequently, participants were subjected to a psychosocial stress paradigm, followed by either a 30-minute SOK elevation intervention (n = 40) or a control condition with nature sounds (n = 29). A second cognitive assessment was administered post-intervention, with continuous HRV measurement through ECG. The results revealed significant HRV changes due to the experimental intervention, though no significant differences were observed between the SOK intervention and control groups. Interestingly, individuals with high trait SOK displayed more stable HRV trajectories, exhibiting a smaller decline during the stress intervention and a milder increase during both the stressor and SOK intervention phases. Overall, these findings do suggest a significant association between SOK, parasympathetic activity, and stress reactivity. These results prompt further investigation into whether personality patterns, such as a strong SOK, may be linked to reduced vagal reactivity and better coping in old age.

Vagal Flexibility Moderates the Links between Observed Sensitive Caregiving in Infancy and Externalizing Behavior Problems in Middle Childhood

This study explored how patterns of physiological stress reactivity underpin individual differences in sensitivity to early rearing experiences and childhood risk for psychopathology. To examine individual differences in parasympathetic functioning, past research has largely relied on static measures of stress reactivity (i.e., residual and change scores) in infancy which may not adequately capture the dynamic nature of regulation across contexts. Using data from a prospective longitudinal study of 206 children (56% African Americans) and their families, this study addressed these gaps by employing the latent basis growth curve model to characterize the dynamic, non-linear patterns of change in infants' respiratory sinus arrhythmia (i.e., vagal flexibility) across the Face-to-Face Still-Face Paradigm. Furthermore, it investigated whether and how infants' vagal flexibility moderates the links between sensitive parenting, observed during a free play task when children were 6 months of age, and parent-report of children's externalizing problems at 7 years of age. Results of the structural equation models revealed that infants' vagal flexibility moderates the predictive relations between sensitive parenting in infancy and children's later externalizing problems. Simple slope analyses revealed that low vagal flexibility, characterized by less suppression and flatter recovery patterns, exacerbated risk for externalizing psychopathology in the context of insensitive parenting. Children with low vagal flexibility also benefited most from sensitive parenting, as indicated by the lower number of externalizing problems. Findings are interpreted in the light of the biological sensitivity to context model and provide evidence for vagal flexibility as a biomarker of individual's sensitivity to early rearing contexts.

Anticipatory cardiac deceleration estimates cognitive performance in virtual reality beyond tonic heart period and heart period variability

Anticipatory cardiac deceleration is the lengthening of heart period before an expected event. It appears to reflect preparation that supports rapid action. The current study sought to bolster anticipatory deceleration as a practical and unique estimator of performance efficiency. To this end, we examined relationships between deceleration and virtual reality performance under low and high time pressure. Importantly, we investigated whether deceleration separately estimates performance beyond basal heart period and basal high-frequency heart rate variability (other vagally influenced metrics related to cognition). Thirty participants completed an immersive virtual reality (VR) cognitive performance task across six longitudinal sessions. Anticipatory deceleration and basal heart period/heart period variability were quantified from electrocardiography collected during pre-task anticipatory countdowns and baseline periods, respectively. At the between-person level, we found that greater anticipatory declaration was related to superior accuracy and faster response times (RT). The relation between deceleration and accuracy was stronger under high relative to low time pressure, when good performance requires greater efficiency. Findings for heart period and heart period variability largely converge with the prior literature, but importantly, were statistically separate from deceleration effects on performance. Lastly, deceleration effects were detected using anticipatory periods that are more practical (shorter and more intermittent) than those typically employed. Taken together, findings suggest that anticipatory deceleration is a unique and practical correlate of cognitive-motor efficiency apart from heart period and heart period variability in virtual reality.

Heart Rate Complexity and Autonomic Modulation Are Associated with Psychological Response Inhibition in Healthy Subjects

BACKGROUND

the ability to suppress/regulate impulsive reactions has been identified as common factor underlying the performance in all executive function tasks. We analyzed the HRV signals (power of high (HF) and low (LF) frequency, Sample Entropy (SampEn), and Complexity Index (CI)) during the execution of cognitive tests to assess flexibility, inhibition abilities, and rule learning.

METHODS

we enrolled thirty-six healthy subjects, recording five minutes of resting state and two tasks of increasing complexity based on 220 visual stimuli with 12 × 12 cm red and white squares on a black background.

RESULTS

at baseline, CI was negatively correlated with age, and LF was negatively correlated with SampEn. In Task 1, the CI and LF/HF were negatively correlated with errors. In Task 2, the reaction time positively correlated with the CI and the LF/HF ratio errors. Using a binary logistic regression model, age, CI, and LF/HF ratio classified performance groups with a sensitivity and specificity of 73 and 71%, respectively.

CONCLUSIONS

this study performed an important initial exploration in defining the complex relationship between CI, sympathovagal balance, and age in regulating impulsive reactions during cognitive tests. Our approach could be applied in assessing cognitive decline, providing additional information on the brain-heart interaction.

Unraveling the cognitive correlates of heart rate variability with the drift diffusion model

The Neurovisceral Integration Model posits a link between resting vagally mediated heart rate variability (vmHRV) and cognitive control. Empirical support for this link is mixed, potentially due to coarse performance metrics such as mean response time (RT). To clarify this issue, we tested the relationships between resting vmHRV and refined estimates of cognitive control- as revealed by the ex-Gaussian model of RT and, to a greater extent, the drift diffusion model (DDM, a computational model of two-choice performance). Participants (N = 174) completed a five-minute resting baseline while ECG was collected followed by a Simon spatial conflict task. The root mean square of successive differences in interbeat intervals was calculated to index resting vmHRV. Resting vmHRV was unrelated to Simon's mean RT and accuracy rates, but was inversely related to the ex-Gaussian parameter reflecting slow RTs (tau); however, this finding was attenuated after adjustment for covariates. High resting vmHRV was related to faster drift rates and slower non-decision times, DDM parameters reflecting goal-directed cognition and sensorimotor processes, respectively. The DDM effects survived covariate adjustment and were specific to incongruent trials (i.e., when cognitive control demands were high). Findings suggest a link between vmHRV and cognitive control vis-a-vis drift rate, and potentially, a link between vmHRV and motoric inhibition vis-a-vis non-decision time. These cognitive correlates would have been missed with reliance on traditional performance. Findings are discussed with respect to the inhibitory processes that promote effective performance in high vmHRV individuals.

Physiological stress reactivity and recovery: Some laboratory results transfer to daily life

Stress is a prevalent theme in our daily lives and is related to numerous negative health outcomes. Laboratory research has studied the physiological stress response extensively with objective measures such as vagally-mediated heart rate variability (vmHRV). Recently, the vagal tank theory emerged as a promising approach to predicting adaptive vmHRV levels around stressful events. This study aimed to investigate whether the predictions of the vagal tank theory about vmHRV during stress reactivity and recovery translate into naturalistic stressful events in daily life. Sixty-seven students wore an EcgMove 4 sensor for 4 days to measure vmHRV. Through a combination of device-based and self-report assessment, vmHRV data were segmented into before, during, and after stressful events. VmHRV segments were analyzed with multilevel modeling, accounting for physiological and psychological covariates. VmHRV before stressful events predicted more adaptive vmHRV during the event but not vmHRV recovery afterwards. The results therefore partially support the vagal tank theory's predictions with data from daily life and allow recommendations for future studies of real-world stress reactivity and recovery. The value of intraindividual variations in vmHRV as predictors of adaptive stress response is underscored by these findings and could inform future interventions that seek to increase momentary vmHRV.

Enhanced cardiac vagal tone in mental fatigue: Analysis of heart rate variability in Time-on-Task, recovery, and reactivity

Heart Rate Variability (HRV) has been suggested as a useful tool to assess fatigue-sensitive psychological operations. The present study uses a between and within-subject design with a cognitively demanding task and a documentary viewing condition, to examine the temporal profile of HRV during reactivity, Time-on-Task (ToT), and recovery. In the cognitive task group, participants worked on a bimodal 2-back task with a game-like character (the Gatekeeper task) for about 1.5 hours, followed by a 12-minute break, and a post-break block of performance (about 18 min). In the other group, participants watched documentaries. We hypothesized an increasing vagal-mediated HRV as a function of Time spent on the Gatekeeper task and no HRV change in the documentary viewing group. We also analyzed the trial-based post-response cardiac activity as a physiological associate of task-related motivation. Relative to the documentary-viewing, ToT was associated with an elevated level of subjective fatigue, decreased heart rate, and increased HRV, particularly in the vagal-mediated components. Based on fatigued participants' post-error cardiac slowing, and post-error reaction time analyses, we found no evidence for motivation deficits. The present findings suggest that the parasympathetic branch of the autonomous nervous system functioning as a relaxation system tends to be activated under increasing mental fatigue. In addition, the study shows that many HRV indices also seem to change when individuals are engaged in a prolonged, less fatiguing activity (e.g. documentary viewing). This finding emphasizes the relevance of comparisons/control conditions in ToT experiments.