The relationship between resting heart rate and aggression in males is racially variant

Although resting heart rate is thought to be a generalizable risk factor for aggression, very little research has examined whether this relationship varies by race. We addressed this limitation using longitudinal data from the Pittsburgh Youth Study. Current data are from 197 men who participated in a teenage biosocial study (mean age = 15.7 years) and adult follow-up study (mean age = 32.1 years). Teenage resting heart rate interacted with race to predict teenage and adult aggression. The relationship between heart rate and aggression was significant in White, but not in Black males. To our knowledge, this is the first study to find that the relationship between resting heart rate and aggression is racially variant, suggesting that resting heart rate may not be a generalizable biomarker for conduct problems. At an intervention-level, findings could contribute to the development of more accurate risk assessment tools that take into account racial variance in risk factors.     

Electroencephalographic and autonomic alterations in subjects with frequent nightmares during pre-and post-REM periods

Abnormal arousal processes, sympathetic influences, as well as wake-like alpha activity during sleep were reported as pathophysiological features of Nightmare Disorder. We hypothesized that in Nightmare Disorder, wake-like cortical activity and peripheral measures linked to arousals would be triggered by physiological processes related to the initiation of REM periods. Therefore, we examined electroencephalographic (EEG), motor and autonomous (cardiac) activity in a group of nightmare (NM) and healthy control (CTL) subjects during sleep-state-transitions while controlling for the confounding effects of trait anxiety. Based on the second-nights’ polysomnographic recordings of 19 Nightmare Disordered (NM) and 21 control (CTL) subjects, we examined the absolute power spectra focusing on the alpha range, measures of heart rate variability (HRV) and motor (muscle tone) activity during pre-REM and post-REM periods, separately. According to our results, the NM group exhibited increased alpha power during pre-REM, but not in post-REM, or stable, non-transitory periods. While CTL subjects showed increased HRV during pre-REM periods in contrast to post-REM ones, NM subjects did not exhibit such sleep state-specific differences in HRV, but showed more stable values across the examined sleep stages and less overall variability reflecting generally attenuated parasympathetic activity during sleep-state-transitions and during stable, non-transitory NREM states. These differences were not mediated by waking levels of trait anxiety. Moreover, in both groups, significant differences emerged regarding cortical and motor (muscle tone) activity between pre-REM and post-REM conditions, reflecting the heterogeneity of NREM sleep. Our findings indicate that NM subjects’ sleep is compromised during NREM–REM transitions, but relatively stabilized after REM periods. The coexistence of sleep-like and wake-like cortical activity in NM subjects seems to be triggered by REM/WAKE promoting neural activity. We propose that increased arousal-related phenomena in NREM–REM transitions might reflect altered emotional processing in NM subjects.     

Subjective and physiological responses to the 35% carbon dioxide challenge in healthy and non-clinical control populations: a meta-analysis and systematic review

Background/Rationale: The carbon dioxide (CO₂) challenge has been reliably used in laboratory settings as a panicogen in clinical populations. However, the magnitude of these effects on healthy and non-clinical control populations are not clear. The aim of this meta-analysis and systematic review is to provide quantitative estimates of those effects. Specifically, the current paper will evaluate the relative efficacy of the CO₂ challenge in eliciting both subjective and physiological arousal in healthy and non-clinical control populations.

Method: A total of 16 articles with 35 independent samples were included in the meta-analysis, while 37 studies with 74 independent samples were included in the systematic review.

Results: Both the meta-analysis and systematic review found the CO₂ challenge to elicit an increase in subjective distress via self-reported anxiety and fear. Physiological responses via blood pressure and heart rate were heterogeneous in studies sampled, with no significant changes observed across studies. Moderator analyses revealed the variations in findings may be attributed to participant screening and invasive sampling.

Discussion: Findings highlight the CO₂ challenge as a useful tool in the provocation of subjective distress. Implications for both the use of the CO₂ challenge and its anticipated effects in healthy and non-clinical control populations are discussed.     

The relationship between anomalistic belief,misperception of chance and the base rate fallacy

Abstract

A poor understanding of probability may lead people to misinterpret every day coincidences and form anomalistic (e.g., paranormal) beliefs. We investigated the relationship between anomalistic belief (including type of belief) and misperception of chance and the base rate fallacy across both anomalistic and control (i.e., neutral) contexts. Greater anomalistic belief was associated with poorer performance for both types of items; however there were no significant interactions between belief and context. For misperception of chance items, only experiential (vs. theoretical) anomalistic beliefs predicted more errors. In contrast, overall anomalistic belief was positively related to the base rate fallacy but no specific subtype of anomalistic belief was a significant predictor. The results indicate misperception of chance may lead people to interpret coincidental events as having an anomalistic cause, and a poor understanding of base rates may make people more prone to forming anomalistic beliefs.