Melissa R. Weiner

INSULA AND ANTERIOR CINGULATE GABA LEVELS IN POSTTRAUMATIC STRESS DISORDER: PRELIMINARY FINDINGS USING MAGNETIC RESONANCE SPECTROSCOPY

Increased reactivity of the insular cortex and decreased activity of the dorsal anterior cingulate cortex (ACC) are seen in functional imaging studies of posttraumatic stress disorder (PTSD), and may partly explain the persistent fear and anxiety proneness that characterize the disorder. A possible neurochemical correlate is altered function of the inhibitory neurotransmitter gamma‐aminobutyric acid (GABA). We report results from what we believe is the first study applying proton magnetic resonance spectroscopy (1H‐MRS) to measure brain GABA in PTSD.

CORTICO-LIMBIC RESPONSES TO MASKED AFFECTIVE FACES ACROSS PTSD, PANIC DISORDER, AND SPECIFIC PHOBIA

Exaggerated amygdala and reduced ventromedial prefrontal cortex (vmPFC) responsiveness during emotional processing have been reported in studies examining individual anxiety disorders. Studies are needed, however, which directly compare activation of amygdalo‐cortical circuitry across multiple anxiety disorders within the same study. Here we compared cortico‐limbic neurocircuitry across three different anxiety disorders using a well‐validated emotional probe task.

Gray matter correlates of Trait and Ability models of emotional intelligence

Research suggests that emotional intelligence capacities may be related to the functional integrity of the corticolimbic regions including the ventromedial prefrontal cortex, insula, and amygdala. No study has yet examined regional brain volumes in relation to the two dominant models of emotional intelligence: the Ability model, which posits a set of specific demonstrable capabilities for solving emotional problems, and the Trait model, which proposes a set of stable emotional competencies that can be assessed through subjectively rated self-report scales. In 36 healthy participants, we correlated scores on the Mayer–Salovey–Caruso Emotional Intelligence Test (an Ability measure) and the Bar-On Emotional Quotient Inventory (a Trait measure) with regional brain volumes using voxel-based morphometry. Total Mayer–Salovey–Caruso Emotional Intelligence Test scores were positively correlated with the left insula grey matter volume. The Strategic emotional intelligence subscale correlated positively with the left ventromedial prefrontal cortex and insular volume. In contrast, for the Bar-On Emotional Quotient Inventory, Stress Management scores correlated positively with the bilateral ventromedial prefrontal cortex volume. Amygdala volumes were unrelated to emotional intelligence measures. Findings support the role of the ventromedial prefrontal cortex and insula as key nodes in the emotional intelligence circuitry.

Habitual ‘sleep credit’ is associated with greater grey matter volume of the medial prefrontal cortex, higher emotional intelligence and better mental health

In modern society, people often fail to obtain the amount of sleep that experts recommend for good health and performance. Insufficient sleep can lead to degraded cognitive performance and alterations in emotional functioning. However, most people also acknowledge that on a regular basis they obtain more sleep than they subjectively perceive they need at a minimum to stave off performance decrements, a construct we describe as subjective ‘sleep credit’. Few people would contest the notion that getting more sleep is better, but data on both behavioural and neuroanatomical correlates of ‘sleep credit’ are surprisingly limited. We conducted a voxel‐based morphometric study to assess cerebral grey matter correlates of habitually sleeping more than ones subjective requirements. We further tested whether these structural correlates are associated with perceived emotional intelligence and indices of psychopathology while controlling for age, gender, and total intracranial volume. In a sample of 55 healthy adults aged 18–45 years (28 males, 27 females), whole‐brain multiple regression showed that habitual subjective ‘sleep credit’ was correlated positively with grey matter volume within regions of the left medial prefrontal cortex and right orbitofrontal gyrus. Volumes were extracted and regressed against self‐report emotion and psychopathology indices. Only grey matter volume of the medial prefrontal cortex cluster correlated with greater emotional intelligence and lower scores on several indices of psychopathology. Findings converge with previous evidence of the role of the medial prefrontal cortex in the relationship between sleep and emotional functioning, and suggest that behaviour and brain structure vary with habitual ‘sleep credit’.

Voxel-based morphometric gray matter correlates of posttraumatic stress disorder.

Posttraumatic stress disorder (PTSD) is associated with functional abnormalities within a neurocircuitry that includes the hippocampus, amygdala, and medial prefrontal cortex. Evidence of structural abnormalities within these regions, and their association with PTSD severity and symptom burden is, however, sparse. The present study evaluated the relation between indices of gray matter volume and PTSD symptom severity using voxel-based morphometry. Fifteen individuals meeting DSM-IV criteria for PTSD completed the Clinician Administered PTSD Scale and underwent structural magnetic resonance imaging. Greater PTSD severity and avoidance/numbing were correlated with increased gray matter volume of the right amygdala-hippocampal complex. Greater hyper-arousal was associated with reduced gray matter volume in the left superior medial frontal gyrus. Findings are consistent with current neurocircuitry models of PTSD, which posit that the disorder is associated with structural and functional variance within this distributed network.

Self-reported nocturnal sleep duration is associated with next-day resting state functional connectivity

Sleep deprivation affects cerebral metabolism and reduces the functional connectivity among various regions of the brain, potentially explaining some of the associated mood and emotional changes often observed. Prior neuroimaging studies have only examined the effects of sleep deprivation or partial sleep restriction on functional connectivity, but none have studied how such connectivity is associated with normal variations in self-reported sleep duration the night before the scan. We examined the relationship between sleep duration and resting state functional connectivity among healthy volunteers who slept at home according to their own schedules. Thirty-nine healthy individuals aged 18–45 (21 females) completed a questionnaire asking about their recent sleep habits and entries in their sleep diary for the previous night, followed by resting state functional MRI at 3 T. Participants reported sleeping between 5.0 and 8.5 h the night before the scan (M=7.0, SD=0.9). Seed regions were placed in the medial prefrontal cortex and posterior cingulate cortex nodes of the default mode network, regions previously implicated in sleep deprivation. Longer self-reported sleep duration was associated with significantly enhanced functional connectivity between the medial prefrontal cortex and posterior cingulate, as well as greater anticorrelations with parietal, occipital, and lateral prefrontal regions. Findings suggest that even normal variations in sleep duration measured by self-report are related to the strength of functional connectivity within select nodes of the default mode network and its anticorrelated network.

Age Differences in the Association of Social Support and Mental Health in Male U.S. Veterans: Results From the National Health and Resilience in Veterans Study.

OBJECTIVE To examine the associations between multiple aspects of social support-perceived support, structural support, and community integration-and mental health difficulties in younger and older male veterans. Drawing from Socioemotional Selectivity Theory (SST), we hypothesized that greater support would be more strongly negatively related to mental health difficulties in older than younger veterans. DESIGN Cross-sectional Web survey of younger and older male veterans recruited from a contemporary, nationally representative sample of veterans residing in the United States. SETTING Data were drawn from the National Health and Resilience in Veterans Study. PARTICIPANTS Participants were 290 younger male veterans (mean age: 37.0 years, SD: 6.9, range: 21-46) and 326 older male veterans (mean age: 81.7 years, SD: 3.2, range: 78-96). MEASUREMENTS Participants completed measures of sociodemographic and military characteristics, perceived and structural social support, community integration, and mental health difficulties. RESULTS In contrast to SST, higher perceived support was associated with fewer mental health difficulties in younger but not older veterans. In line with SST, community integration was associated with fewer mental health difficulties in older but not younger veterans. Structural support was not associated with mental health difficulties in either group. CONCLUSION Results of this study provide mixed support for SST and suggest that different aspects of social support may help promote the mental health of younger and older male U.S. veterans. Promotion of community engagement may help promote mental health in older veterans, whereas promotion of functional social support may help promote mental health in younger veterans.

Personality and Psychopathic Changes

Sleep deprivation significantly affects cerebral functioning within many areas, including the prefrontal cortex, a region that is critical for the modulation of emotional processes and basic personality functioning. Research suggests that sleep deprivation may affect a variety of cognitive capacities, but some of its most profound and reliable effects appear to be on mood and emotional processing. Sleep deprivation appears to lead to worsening of mood, degraded emotional intelligence, reduced constructive thinking capacities, and suppressed frustration tolerance. There is also evidence that sleep deprivation is associated with a subclinical increase in self-rated symptoms of psychopathology such as somatization, anxiety, depression, and paranoid feelings of persecution and resentment. Paradoxically, among clinically depressed patients, sleep deprivation can actually have short-lived mood-elevating effects.