Distinct neural markers of evidence accumulation index metacognitive processing before and after simple visual decisions.

Perceptual decision-making is affected by uncertainty arising from the reliability of incoming sensory evidence (perceptual uncertainty) and the categorization of that evidence relative to a choice boundary (categorical uncertainty). Here, we investigated how these factors impact the temporal dynamics of evidence processing during decision-making and subsequent metacognitive judgments. Participants performed a motion discrimination task while electroencephalography was recorded. We manipulated perceptual uncertainty by varying motion coherence, and categorical uncertainty by varying the angular offset of motion signals relative to a criterion. After each trial, participants rated their desire to change their mind. High uncertainty impaired perceptual and metacognitive judgments and reduced the amplitude of the centro-parietal positivity, a neural marker of evidence accumulation. Coherence and offset affected the centro-parietal positivity at different time points, suggesting that perceptual and categorical uncertainty affect decision-making in sequential stages. Moreover, the centro-parietal positivity predicted participants' metacognitive judgments: larger predecisional centro-parietal positivity amplitude was associated with less desire to change one's mind, whereas larger postdecisional centro-parietal positivity amplitude was associated with greater desire to change one's mind, but only following errors. These findings reveal a dissociation between predecisional and postdecisional evidence processing, suggesting that the CPP tracks potentially distinct cognitive processes before and after a decision.

Intranasal Mupirocin to Reduce Surgical Site Infection Post Cardiac Surgery: A Review of the Literature.

Sternal wound infections after cardiac surgery are associated with high rates of morbidity and mortality. One of the known risk factors of sternal wound infection is Staphylococcus aureus colonisation. Intranasal mupirocin decolonisation therapy implemented pre-operatively appears to be an effective preventative measure in reducing sternal wound infections post-cardiac surgery. Therefore, the main aim of this review is to evaluate the current literature regarding the use of intranasal mupirocin before cardiac surgery and its impact on sternal wound infection rates.

On second thoughts: changes of mind in decision-making.

The ability to change initial decisions in the face of new or potentially conflicting information is fundamental to adaptive behavior. From perceptual tasks to multiple-choice tests, research has shown that changes of mind often improve task performance by correcting initial errors. Decision makers must, however, strike a balance between improvements that might arise from changes of mind and potential energetic, temporal, and psychological costs. In this review, we provide an overview of the change-of-mind literature, focusing on key behavioral findings, computational mechanisms, and neural correlates. We propose a conceptual framework that comprises two core decision dimensions - time and evidence source - which link changes of mind across decision contexts, as a first step toward an integrated psychological account of changes of mind.

The effects of acute stress on attentional networks and working memory in females.

Neurobiological models indicate that acute stress facilitates bottom-up stimulus processing while impairing top-down executive control. To test this hypothesis, the present study investigated the effects of acute stress on behavioural and electrophysiological measures of human attentional networks, and behavioural measures of working memory. Forty-five female participants (Mage = 22.1, SD = 2.4) performed the Attention Network Test (ANT) and the n-back task before and after the Maastricht Acute Stress Test (MAST; n = 23) or a non-stressful MAST-placebo (n = 22). Subjective distress ratings and salivary cortisol concentrations revealed a successful stress induction. Increased salivary cortisol at baseline was associated with slower reaction times across both tasks, suggesting a general detrimental effect of cortisol on cognitive functioning. Despite these findings, however, the hypothesised effects of the acute stress manipulation were not found for either task. Supplementary analyses indicated that these results were unrelated to the magnitude or duration of the stress response. Our results therefore suggest the standard version of the ANT may be insensitive to the effects of acute stress, and that higher cognitive loads may be necessary to observe stress effects on the n-back task.

Endocannabinoid reactivity to acute stress: Investigation of the relationship between salivary and plasma levels.

The endogenous cannabinoid (eCB) system has been shown in animal models to regulate the initiation and termination of central nervous responses to stress. In human studies, the role of peripherally measured eCBs is much less clear and the effect in salivary eCBs has not been studied. In this study, we use a novel method to quantify cortisol and eCBs arachidonoyl ethanolamide (AEA) and 2-arachidonoyl glycerol (2-AG) in human saliva, as well as in plasma samples. Forty-five females and 32 males completed a mixed physiological/psychosocial stress-induction study where saliva, and blood samples in males, were collected at baseline, immediately following, 30-minutes following, and 45-minutes following stress induction. Cortisol significantly increased after stress, but there were sex differences in the cortisol response to stress, with females having higher cortisol after stress compared to males. There was a significant increase in salivary levels of 2-AG immediately following stress induction, but no effect of AEA. Salivary AEA was higher in males compared to females. Surprisingly, there was no effect of stress on plasma AEA or 2-AG levels in the male cohort, though small effect sizes for 2-AG were observed, which is consistent with most other human literature. This study is the first to show that the eCB system is active in human saliva and is responsive to acute stress, possibly as part of the sympathetic nervous system response.

Anger Dimensions and Mental Health Following a Disaster: Distribution and Implications After a Major Bushfire.

Anger is an important dimension of affect and a prominent feature of posttraumatic mental health, but it is commonly overlooked in postdisaster settings. We aimed to examine the distribution and implications of significant anger problems in the aftermath of a natural disaster, via analyses of Beyond Bushfires survey data from 736 residents of rural communities 5 years after the 2009 Black Saturday bushfires in Victoria, Australia. Assessments included the five-item Dimensions of Anger Reaction (DAR-5) scale along with measures of PTSD, depression, and significant mental illness, and indicators of life satisfaction, suicidality, hostile aggressive behavior, and violence exposure. The results indicated that approximately 10% of respondents from areas highly affected by the bushfires scored above the provisional cutoff criteria for significant anger problems on the DAR-5, which was a more than 3-fold increase, OR = 3.26, relative to respondents from areas of low-to-moderate bushfire impact. The rates were higher among women, younger participants, and those who were unemployed, and co-occurred commonly, although not exclusively, with other postdisaster mental health problems. Anger problems were also associated with lower life satisfaction, ß = -.31, an 8-fold increase in suicidal ideation, OR = 8.68, and a nearly 13-fold increase in hostile aggressive behavior, OR = 12.98. There were associations with anger problems and violence exposure, which were reduced when controlling for covariates, including probable PTSD. The findings provide evidence indicating that anger is a significant issue for postdisaster mental health and should be considered routinely alongside other posttraumatic mental health issues.

Posttraumatic Stress Disorder in Primary Care: A Study of General Practices in England.

Posttraumatic Stress Disorder (PTSD) may be a common issue in primary care in the UK, but there have been no studies of all-cause PTSD in general samples of attenders in this country. The current paper thus explores the extent and distribution of probable PTSD among patients attending general practices in England. Cross-sectional survey data from adult patients (n = 1058) attending 11 general practices in southwest England were analysed. Patients were recruited from waiting rooms and completed anonymous questionnaires, including measures of depression, anxiety and risky alcohol use. Current probable PTSD was measured using the 4-item Primary Care PTSD Scale (PC-PTSD). Results indicated 15.1% of patients that exhibited probable PTSD (PC-PTSD ≥ 3), with higher levels observed in practices from deprived areas. There were 53.8% of patients with probable PTSD that expressed the desire for help with these issues. The analyses suggested that rates were lowest among older adults, and highest among patients who were not in cohabitating relationships or were unemployed. Measures of anxiety and depression were associated with 10-fold and 16-fold increases in risk of probable PTSD, respectively, although there were no discernible associations with risky drinking. Such preliminary findings highlight the need for vigilance for PTSD in routine general practice in the UK, and signal a strong need for additional research and attention in this context.