The relationship between acute stress and neurophysiological and behavioral measures of food-related inhibitory control: An event-related potential (ERP) study.

Stress influences many health-related behaviors including diet and nutrition intake, often resulting in increased calorie intake, fewer healthy eating behaviors, and poorer nutrition. Food intake is modulated by inhibitory control and has important implications for our physical, mental, and emotional health. Yet, little is known about the relationship between stress and food-related inhibitory control. We tested the influence of a short-term experimental stressor on behavioral and event-related potential (ERP; N2 and P3 components) measures of food-related inhibitory control. Ninety-seven healthy participants were randomly assigned to complete the Trier Social Stress Test (TSST) (n = 48, 27 females [52.9%]) or a neutral control condition (n = 49, 35 females [70%]) immediately followed by food-specific go/no-go and neutral go/no-go tasks while electroencephalogram (EEG) data were recorded. Stress levels were successfully manipulated, with heightened self-report and physiological measures (heart rate and systolic blood pressure) of the stress response in individuals who completed the TSST compared to control. As expected, the high calorie food-specific go/no-go task elicited larger N2 amplitude than the neutral task. N2 component amplitude was also significantly larger following the TSST relative to the control task. There were no significant between-group or task differences for P3 amplitude or behavioral measures. Findings suggest heightened N2 amplitude following psychological stress that is not specific to food or inhibition processes and may reflect heightened arousal following stress. Future research in individuals with overweight/obesity or experiencing chronic stress will further clarify the role of stress in food-related inhibitory control.

Does type of active workstation matter? A randomized comparison of cognitive and typing performance between rest, cycling, and treadmill active workstations.

Active workstations are associated with improved health outcomes, but differences in cognitive and typing outcomes between the types of active workstations are unclear. We addressed two main questions: (1) Are there differences in cognitive and typing performance between seated and active workstations? (2) Are there differences in cognitive and typing performance between cycling and treadmill workstations, specifically? Participants included 137 healthy young adults (74 female, mean age = 20.8 years) who completed two sessions. At session one (baseline), all participants completed cognitive and typing tests including the Rey-Auditory Verbal Learning Test, Paced Auditory Serial Addition Test, a typing test, and a flanker task while sitting at rest. At session two, participants were randomized to an active workstation group (treadmill or cycling desk) during which they performed the tests listed above in a randomized fashion, using alternate versions when available. Participants showed significantly better attention and cognitive control scores during the active session as compared to the seated session, but worse verbal memory scores during the active session. Participants were faster and more accurate at typing during the active session relative to the seated session. There were no significant differences between cycling or treadmill workstations on any cognitive or typing outcomes. Improvements during active sessions may be influenced by practice effects, although alternate forms were used when possible. We conclude that active workstations do not seem to largely impact cognitive abilities, with the exception of a slight decrease in verbal memory performance. Findings suggest active workstations, whether walking or cycling, are useful to improve physical activity, particularly when completing tasks that do not require verbal memory recall.

The Association Between Experimentally Induced Stress, Performance Monitoring, and Response Inhibition: An Event-Related Potential (ERP) Analysis.

Psychological stress is increasingly associated with alterations in performance and affect. Yet, the relationship between experimentally induced psychological stress and neural indices of performance monitoring and error processing, as well as response inhibition, are unclear. Using scalp-recorded event-related potentials (ERPs), we tested the relationship between experimental stress, using the Trier Social Stress Test (TSST), and the error-related negativity (ERN), error positivity (Pe), and N2 ERP components. A final sample of 71 undergraduate students were randomly assigned to go through the TSST (n = 36; 18 female) or a brief mindfulness relaxation exercise (n = 35; 16 female) immediately followed by a go/no-go task while electroencephalogram (EEG) data were collected. Salivary cortisol, heart rate, and blood pressure confirmed increased physiological stress in the TSST group relative to control. Reaction times, accuracy, and post-error slowing did not differ by stress group. Two-group (TSST, control) by 2-trial type (correct, incorrect for ERN/Pe; go correct, no-go correct for N2) repeated measures ANOVAs for the ERN, Pe, and N2 showed the expected main effects of trial type; neither the ERN nor the N2 ERP components showed interactions with the stress manipulation. In contrast, the Pe component showed a significant Group by Trial interaction, with reduced Pe amplitude following the stress condition relative to control. Pe amplitude did not, however, correlate with cortisol reactivity. Findings suggest a reduction in Pe amplitude following experimental stress that may be associated with reduced error awareness or attention to errors following the TSST. Given the variability in the extant literature on the relationship between experimentally induced stress and neurophysiological reflections of performance monitoring, we provide another point of data and conclude that better understanding of moderating variables is needed followed by high-powered replication studies to get at the nuance that is not yet understood in the relationship between induced stress and performance monitoring/response inhibition processes.

Quantifying evidential value and selective reporting in recent and 10-year past psychophysiological literature: A pre-registered P-curve analysis.

Selective reporting (i.e., only reporting significant findings as opposed to all analyses or results) is a questionable research practice that undermines the integrity of published research. Psychophysiology research may be susceptible to selective reporting, given the high number of decision points and methodological complexity in analyses of psychophysiology data. We aimed to assess the presence of selective reporting and evidential value (i.e., that significant results are due to true underlying effects) in recent and past psychophysiological research by utilizing p-curve analyses. Study protocols and methods were pre-registered on the Open Science Framework (OSF). P-values and the associated test statistics were extracted from articles in the most recent issue (as of January 2018) and 10-year previous counterpart issue of three major psychophysiology journals: Psychophysiology, International Journal of Psychophysiology, and Journal of Psychophysiology. Using the p-curve application, 10 primary p-curves were conducted: all recent articles, all past articles, recent articles split by journal, past articles split by journal, recent cognitive electrophysiology articles, and past cognitive electrophysiology articles. Evidential value and generally adequate average power (≥78% average power) were present in all p-curves, except those that only included articles from the Journal of Psychophysiology because of the small number of articles published in the journal. Findings provide some positive news and indicate that, generally, results were not selectively reported, and selective reporting may not be a primary issue for this sample of psychophysiological research. Future p-curve analyses examining sub-disciplines of psychophysiology are recommended.