Functional connectivity of the auditory cortex in women with trauma-related disorders who hear voices.

BACKGROUND: 'Voice-hearing' (VH) is a transdiagnostic experience that is common in trauma-related disorders (trauma-D). However, the neural substrates underlying trauma-related VH remain largely unexplored. While auditory perceptual dysfunction is among the abnormalities implicated in schizophrenia VH, whether VH in trauma-D also involves auditory perceptual alterations is unknown. METHODS: We investigated auditory cortex (AC)-related functional connectivity (FC) in n=65 women with trauma-D related to childhood abuse with varying severities of VH. Using a novel, computationally-driven and individual-specific method of functionally parcellating the brain, we calculated the FC of two distinct AC subregions-Heschl's gyrus (HG, corresponding to primary AC) and lateral superior temporal gyrus (lSTG, in non-primary AC)- with both the cerebrum and cerebellum. We then measured the association between VH severity and FC using leave-one-out cross validation within the cerebrum, and voxel-wise multiple regression analyses in the cerebellum. RESULTS: We found that VH severity positively correlated with left lSTG-frontoparietal network FC, while it negatively correlated with FC between left lSTG and both cerebral and cerebellar representations of the default mode network. VH severity was not predicted by FC of left HG or right AC subregions. CONCLUSIONS: Our findings point to altered interactions between auditory perceptual processing and higher-level processes related to self-reference and executive functioning. This is the first study to show alterations in auditory cortical connectivity in trauma-related VH. While VH in trauma-D appears to be mediated by brain networks that are also implicated in schizophrenia VH, the results suggest a unique mechanism that could distinguish VH in trauma-D.

The effects of transcutaneous auricular vagal nerve stimulation on cognition in healthy individuals: A meta-analysis.

OBJECTIVE: Transcutaneous auricular vagal nerve stimulation (taVNS) may benefit cognition in healthy adults but may differentially affect specific domains of cognitive function. Currently, optimal stimulation parameters of taVNS have yet to be identified and the overall effectiveness of this approach remains unclear. METHOD: A literature review and random effects meta-analysis evaluated the effects of taVNS on cognitive performance outcomes across domains of function and outcome metrics (accuracy and response times). Subgroup meta-analyses and meta-regression models explored the moderating effects of stimulation parameters on performance outcomes. RESULTS: Meta-analyses on 19 eligible studies indicated a weighted effect size of 0.21 for the effect of taVNS on overall cognitive performance, with significant effects on measures of executive function and measures of accuracy. Parameter meta-analyses indicated that stimulation site was most associated with improvements in executive function (gtragus = 2.39, gcymba concha = 0.48; Q = 39.84, p < .0001; ß = -2.33, p = .03). CONCLUSIONS: taVNS may improve cognition, particularly executive function, and stimulation parameters may differentially influence outcomes. Continued research into the effects of taVNS as well as optimal stimulation parameters will be beneficial. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Manual segmentation of the human bed nucleus of the stria terminalis using 3T MRI.

The bed nucleus of the stria terminalis (BNST)-a small gray matter region located in the basal forebrain-has been implicated in both anxiety and addiction based on compelling evidence from rodent and non-human primate studies. However, the BNST's small size and proximity to other gray matter regions has hindered non-invasive study in human subjects using standard neuroimaging methods. While initial studies have benefitted from a BNST mask created from a single human subject using a 7T scanner, individual variability is likely-especially in patient populations-thus a manual segmentation protocol is needed. Here we report on the development of a reliable manual segmentation protocol performed on 3T MRI images using a scanning sequence that provides high gray matter/white matter/cerebrospinal fluid contrast. Inter- and intra-rater reliabilities, measured in 10 healthy individuals, demonstrate that the protocol can be reliably implemented (intra-rater Dice similarity coefficient≥0.85, inter-rater≥0.77). This BNST tracing protocol provides the necessary foundation for future 3T MRI studies of the BNST in healthy controls and patient populations.

Personality traits predicting quality of life and overall functioning in schizophrenia.

INTRODUCTION: Clinical symptoms and sociodemographic variables predict level of functioning and quality of life in patients with schizophrenia. However, few studies have examined the effect of personality traits on quality of life and overall functioning in schizophrenia. Personality traits are premorbid to illness and may predict the way patients experience schizophrenia. The aim of this study was to examine the individual and additive effects of two core personality traits-neuroticism and extraversion-on quality of life and functioning. METHODS: Patients with schizophrenia-spectrum disorders (n=153) and healthy controls (n=125) completed personality and quality of life questionnaires. Global functioning was assessed during a clinician-administered structured interview. Neuroticism and extraversion scores were analyzed both as continuous variables and as categorical extremes (High versus Normal Neuroticism, Low versus Normal Extraversion). RESULTS: Quality of life was significantly associated with neuroticism, extraversion, and the neuroticism×diagnosis and extraversion×diagnosis interactions. For patients, a lower neuroticism score (in the normal range) was associated with quality of life scores comparable to controls; whereas high neuroticism scores in patients were associated with the lowest quality of life. For overall functioning, only diagnosis had a significant effect. CONCLUSION: Neuroticism modulates quality of life and may provide an important key to improving the life of patients with schizophrenia.