To go or not to go: Personality, behaviour and neurophysiology of impulse control in men and women

Molecular mechanisms underlying resting-state brain functional correlates of behavioral inhibition

Previous literature has established the presence of sex differences in behavioral inhibition as well as its neural substrates and related disease risk. However, there is limited evidence that speaks directly to the question of whether or not there are sex-dependent associations between behavioral inhibition and resting-state brain function and, if so, how they are modulated by the underlying molecular mechanisms. We computed functional connectivity density (FCD) using resting-state functional MRI data to examine their associations with behavioral inhibition ability measured using a Go/No-Go task across a large cohort of 510 healthy young adults. Then, we examined the spatial relationships of the FCD correlates of behavioral inhibition with gene expression and neurotransmitter atlases to explore their potential genetic architecture and neurochemical basis. A significant negative correlation between behavioral inhibition and FCD in the left superior parietal lobule was found in females but not males. Further spatial correlation analyses demonstrated that the identified neural correlates of behavioral inhibition were associated with expression of gene categories predominantly implicating essential components of the cerebral cortex (glial cell, neuron, axon, dendrite, and synapse) and ion channel activity, as well as were linked to the serotonergic system. Our findings may not only yield important insights into the molecular mechanisms underlying the female-specific neural substrates of behavioral inhibition, but also provide a critical context for understanding how biological sex might contribute to variation in behavioral inhibition and its related disease risk.

The Black Unicorn Effect: Micro-daily Events and Satisfaction Decrease the COVID-19 Xenophobia, but Only for Those With Low Levels of Neuroticism

Drawing on the behavioral concordance model and the trait activation theory, this study examined how and when daily micro-events influence COVID-19 xenophobic attitudes. First, we examined the mediating role of satisfaction, and then, tested the moderating role of neuroticism in the mediated relationship. Overall, 340 working adults volunteered to participate in this study. The findings revealed that (1) satisfaction mediated the negative relationship between daily micro-events and xenophobic attitudes and (2) neuroticism moderated this relationship such that xenophobic attitudes increased for neurotic individuals, even when their satisfaction increased. Our findings contribute to understanding the relationship between daily micro-events and COVID-19 xenophobia and provide empirical evidence for the combined effects of personality factors and affective factors on xenophobic attitudes. Furthermore, we evidence the existence of the black unicorn effect, that is, neurotic individuals tend to transpose their neurotic cognitions and emotions to xenophobic attitudes despite the uplifting and satisfying nature of positive events.

Sex differences in executive control: A systematic review of functional neuroimaging studies

The number of studies investigating sex differences in executive functions, particularly those using human functional neuroimaging techniques, has risen dramatically in the past decade. However, the influences of sex on executive function are still underexplored and poorly characterized. To address this, we conducted a systematic literature review of functional neuroimaging studies investigating sex differences in three prominent executive control domains of cognitive set-shifting, performance monitoring, and response inhibition. PubMed, Web of Science, and Scopus were systematically searched. Following the application of exclusion criteria, 21 studies were included, with a total of 677 females and 686 males. Ten of these studies were fMRI and PET, eight were EEG, and three were NIRS. At present, there is evidence for sex differences in the neural networks underlying all tasks of executive control included in this review suggesting males and females engage different strategies depending on task demands. There was one task exception, the 2-Back task, which showed no sex differences. Due to methodological variability and the involvement of multiple neural networks, a simple overarching statement with regard to gender differences during executive control cannot be provided. As such, we discuss limitations within the current literature and methodological considerations that should be employed in future research. Importantly, sex differences in neural mechanisms are present in the majority of tasks assessed, and thus should not be ignored in future research. PROSPERO registration information: CRD42019124772.

Sleep and suicidality in school-aged adolescents: A prospective study with 2-year follow-up

Current evidence about the association between sleep and suicide are conflicting. This study aimed to investigate the association between sleep duration and quality with suicidal behaviors in a group of school-aged adolescents in China. The baseline survey was conducted among Chinese adolescents aged 12-13 years in October 2016. All participants were asked to complete a self-administered questionnaire. After 2 years follow-up, a total of 1513 adolescents completed the follow-up. The multivariable logistic regression analysis showed that shorter sleep duration (<8 h per night) in baseline was associated with an increased likelihood of suicidality in boys [suicidal ideation, adjusted odds ratio (OR)=2.18, 95% confidence interval (CI)=1.97 to 3.98; suicide planning, OR=2.47, 95% CI=1.22 to 5.01; suicide attempt, OR=2.97, 95% CI=1.39 to 6.38]. Similarly, poor sleep quality [Pittsburgh Sleep Quality Index (PSQI) ≧ 5] was associated with an increased likelihood of suicidal ideation and suicide planning in boys (OR=2.14, 95% CI=1.15 to 3.99 and OR=2.47, 95% CI=1.16 to 5.25, respectively). This study indicates that school-aged boys are more likely to experience suicidality in exposure to short sleep or poor sleep quality.