Frequency-domain analysis of transient visual evoked potentials in schizophrenia.

Purpose: Frequency-domain measures were applied to characterize neural deficits in individuals with schizophrenia using transient visual evoked potentials (tVEP). These measures were compared with conventional time-domain measures to elucidate underlying neurophysiological mechanisms and examine the value of frequency analysis.

Methods: Four frequency bands of activity identified in previous work were explored with respect to magnitude (spectral power), timing (phase), a combined measure, magnitude-squared coherence (MSC), and compared to amplitudes and times of prominent deflections in the response.

Remote Assessment of Negative Symptoms of Schizophrenia.

In contrast to the validated scales for face-to-face assessment of negative symptoms, no widely accepted tools currently exist for remote monitoring of negative symptoms. Remote assessment of negative symptoms can be broadly divided into 3 categories: (1) remote administration of an existing negative-symptom scale by a clinician, in real time, using videoconference technology to communicate with the patient; (2) direct inference of negative symptoms through detection and analysis of the patient's voice, appearance, or activity by way of the patient's smartphone or other device; and (3) ecological momentary assessment, in which the patient self-reports their condition upon receipt of periodic prompts from a smartphone or other device during their daily routine. These modalities vary in cost, technological complexity, and applicability to the different negative-symptom domains.

Association between COVID-19 risk-mitigation behaviors and specific mental disorders in youth.

Background: Although studies of adults show that pre-existing mental disorders increase risk for COVID-19 infection and severity, there is limited information about this association among youth. Mental disorders in general as well as specific types of disorders may influence the ability to comply with risk-mitigation strategies to reduce COVID-19 infection and transmission.

Methods: Youth compliance (rated as "Never," "Sometimes," "Often," or "Very often/Always") with risk mitigation was reported by parents on the CoRonavIruS Health Impact Survey (CRISIS) in January 2021.

Cocaine perturbs mitovesicle biology in the brain.

Cocaine, an addictive psychostimulant, has a broad mechanism of action, including the induction of a wide range of alterations in brain metabolism and mitochondrial homeostasis. Our group recently identified a subpopulation of non-microvesicular, non-exosomal extracellular vesicles of mitochondrial origin (mitovesicles) and developed a method to isolate mitovesicles from brain parenchyma. We hypothesised that the generation and secretion of mitovesicles is affected by mitochondrial abnormalities induced by chronic cocaine exposure.

Harmonizing bifactor models of psychopathology between distinct assessment instruments: Reliability, measurement invariance, and authenticity.

Objectives: Model configuration is important for mental health data harmonization. We provide a method to investigate the performance of different bifactor model configurations to harmonize different instruments.

Methods: We used data from six samples from the Reproducible Brain Charts initiative (N = 8,606, ages 5-22 years, 41.

Saccadic inhibition during free viewing in macaque monkeys.

Through the process of saccadic inhibition, visual events briefly suppress eye movements including microsaccades. In humans, saccadic inhibition has been shown to occur in response to the presentation of parafoveal or peripheral visual distractors during fixation and target-directed saccades and to physical changes of behaviorally relevant visual objects. In monkeys performing tasks that controlled eye movements, saccadic inhibition of microsaccades and target-directed saccades has been shown.

HNN-core: A Python software for cellular and circuit-level interpretation of human MEG/EEG.

HNN-core is a library for circuit and cellular level interpretation of non-invasive human magneto-/electro-encephalography (MEG/EEG) data. It is based on the Human Neocortical Neurosolver (HNN) software (Neymotin et al., 2020), a modeling tool designed to simulate multiscale neural mechanisms generating current dipoles in a localized patch of neocortex.

Phosphorus metabolism in the brain of cognitively normal midlife individuals at risk for Alzheimer's disease.

Background: Neurometabolic abnormalities and amyloid-beta plaque deposition are important early pathophysiologic changes in Alzheimer's disease (AD). This study investigated the relationship between high-energy phosphorus-containing metabolites, glucose uptake, and amyloid plaque using phosphorus magnetic resonance spectroscopy (P-MRS) and positron emission tomography (PET).

Methods: We measured P-MRS, fluorodeoxyglucose (FDG)-PET, and Pittsburgh Compound B (PiB)-PET in a cohort of 20 cognitively normal middle-aged adults at risk for AD.

When do contrast sensitivity deficits (or enhancements) depend on spatial frequency? Two ways to avoid spurious interactions.

Studies across a broad range of disciplines-from psychiatry to cognitive science to behavioural neuroscience-have reported on whether the magnitude of contrast sensitivity alterations in one group or condition varies with spatial frequency. Significant interactions have often gone unexplained or have been used to argue for impairments in specific processing streams. Here, we show that interactions with spatial frequency may need to be re-evaluated if the inherent skew/heteroscedasticity was not taken into account or if visual acuity could plausibly differ across groups or conditions.

Neural function underlying reward expectancy and attainment in adolescents with diverse psychiatric symptoms.

Reward dysfunction has been hypothesized to play a key role in the development of psychiatric conditions during adolescence. To help capture the complexity of reward function in youth, we used the Reward Flanker fMRI Task, which enabled us to examine neural activity during expectancy and attainment of both certain and uncertain rewards. Participants were 84 psychotropic-medication-free adolescents, including 67 with diverse psychiatric conditions and 17 healthy controls.

Neuroanatomical correlates of macrostructural receptive abilities in narrative discourse in unilateral left hemisphere stroke: A behavioural and voxel-based morphometry study.

Background: Little is known about story retelling and comprehension abilities in groups with lower levels of education and socio-economic status (SES). A growing body of evidence suggests the role of an extended network supporting narrative comprehension, but few studies have been conducted in clinical populations, even less in developing countries.

Aims: To extend our knowledge of the impact of a stroke on macrostructural aspects of discourse processes, namely main and complementary information, in individuals with middle-low to low SES and low levels of education.

Efficacy of Sulforaphane in Treatment of Children with Autism Spectrum Disorder: A Randomized Double-Blind Placebo-Controlled Multi-center Trial.

Sulforaphane has been reported to possibly improve core symptoms associated with autism spectrum disorders from mostly small size studies. Here we present results of a larger randomized clinical trial (N = 108) in China. There were no significant changes in caregiver rated scales between sulforaphane and placebo groups.

Computerized cognitive and social cognition training in schizophrenia for impulsive aggression.

Background: Schizophrenia is associated with an elevated risk for impulsive aggression for which there are few psychosocial treatment options. Neurocognitive and social cognitive deficits have been associated with aggression with social cognitive deficits seemingly a more proximal contributor. The current study examined the effects of combining cognitive and social cognition treatment on impulsive aggression among inpatients with chronic schizophrenia and schizoaffective disorder and a history of aggression compared to cognitive remediation treatment alone.

Unified ethical principles and an animal research 'Helsinki' declaration as foundations for international collaboration.

Ethical frameworks are the foundation for any research with humans or nonhuman animals. Human research is guided by overarching international ethical principles, such as those defined in the Helsinki Declaration by the World Medical Association. However, for nonhuman animal research, because there are several sets of ethical principles and national frameworks, it is commonly thought that there is substantial variability in animal research approaches internationally and a lack of an animal research 'Helsinki Declaration', or the basis for one.

Training spiking neuronal networks to perform motor control using reinforcement and evolutionary learning.

Artificial neural networks (ANNs) have been successfully trained to perform a wide range of sensory-motor behaviors. In contrast, the performance of spiking neuronal network (SNN) models trained to perform similar behaviors remains relatively suboptimal. In this work, we aimed to push the field of SNNs forward by exploring the potential of different learning mechanisms to achieve optimal performance.

Deviations from a typical development of the cerebellum in youth are associated with psychopathology, executive functions and educational outcomes.

Background: Understanding deviations from typical brain development is a promising approach to comprehend pathophysiology in childhood and adolescence. We investigated if cerebellar volumes different than expected for age and sex could predict psychopathology, executive functions and academic achievement.

Methods: Children and adolescents aged 6-17 years from the Brazilian High-Risk Cohort Study for Mental Conditions had their cerebellar volume estimated using Multiple Automatically Generated Templates from T1-weighted images at baseline ( = 677) and at 3-year follow-up ( = 447).

Local features drive identity responses in macaque anterior face patches.

Humans and other primates recognize one another in part based on unique structural details of the face, including both local features and their spatial configuration within the head and body. Visual analysis of the face is supported by specialized regions of the primate cerebral cortex, which in macaques are commonly known as face patches. Here we ask whether the responses of neurons in anterior face patches, thought to encode face identity, are more strongly driven by local or holistic facial structure.

Preclinical and randomized clinical evaluation of the p38α kinase inhibitor neflamapimod for basal forebrain cholinergic degeneration.

The endosome-associated GTPase Rab5 is a central player in the molecular mechanisms leading to degeneration of basal forebrain cholinergic neurons (BFCN), a long-standing target for drug development. As p38α is a Rab5 activator, we hypothesized that inhibition of this kinase holds potential as an approach to treat diseases associated with BFCN loss. Herein, we report that neflamapimod (oral small molecule p38α inhibitor) reduces Rab5 activity, reverses endosomal pathology, and restores the numbers and morphology of BFCNs in a mouse model that develops BFCN degeneration.

Enhanced excitability of the hippocampal CA2 region and its contribution to seizure activity in a mouse model of temporal lobe epilepsy.

The hippocampal CA2 region, an area important for social memory, has been suspected to play a role in temporal lobe epilepsy (TLE) because of its resistance to degeneration observed in neighboring CA1 and CA3 regions in both humans and rodent models of TLE. However, little is known about whether alterations in CA2 properties promote seizure generation or propagation. Here, we addressed the role of CA2 using the pilocarpine-induced status epilepticus model of TLE.

Isolation of mitochondria-derived mitovesicles and subpopulations of microvesicles and exosomes from brain tissues.

Extracellular vesicles (EVs) are nanoscale vesicles secreted into the extracellular space by all cell types, including neurons and astrocytes in the brain. EVs play pivotal roles in physiological and pathophysiological processes such as waste removal, cell-to-cell communication and transport of either protective or pathogenic material into the extracellular space. Here we describe a detailed protocol for the reliable and consistent isolation of EVs from both murine and human brains, intended for anyone with basic laboratory experience and performed in a total time of 27 h.

The Association of Life Events Outside the Workplace and Burnout: A Cross-Sectional Study on Nursing Assistants.

Background: Burnout, by definition, is related to adverse chronic workplace stressors. Life events outside the workplace have been associated with an increased risk of psychiatric morbidity. However, it is unknown whether life events outside the workplace increase the severity of burnout.

Autolysosomal acidification failure as a primary driver of Alzheimer disease pathogenesis.

Genetic evidence has increasingly linked lysosome dysfunction to an impaired autophagy-lysosomal pathway (ALP) flux in Alzheimer disease (AD) although the relationship of these abnormalities to other pathologies is unclear. In our recent investigation on the origin of impaired autophagic flux in AD, we established the critical early role of defective lysosomes in five mouse AD models. To assess alterations of autophagy and ALP vesicle acidification, we expressed eGFP-mRFP-LC3 specifically in neurons.

The Neurobiology of Infant Attachment-Trauma and Disruption of Parent-Infant Interactions.

Current clinical literature and supporting animal literature have shown that repeated and profound early-life adversity, especially when experienced within the caregiver-infant dyad, disrupts the trajectory of brain development to induce later-life expression of maladaptive behavior and pathology. What is less well understood is the immediate impact of repeated adversity during early life with the caregiver, especially since attachment to the caregiver occurs regardless of the quality of care the infant received including experiences of trauma. The focus of the present manuscript is to review the current literature on infant trauma within attachment, with an emphasis on animal research to define mechanisms and translate developmental child research.

Reduced calcium levels and accumulation of abnormal insulin granules in stem cell models of HNF1A deficiency.

Mutations in HNF1A cause Maturity Onset Diabetes of the Young (HNF1A-MODY). To understand mechanisms of β-cell dysfunction, we generated stem cell-derived pancreatic endocrine cells with hypomorphic mutations in HNF1A. HNF1A-deficient β-cells display impaired basal and glucose stimulated-insulin secretion, reduced intracellular calcium levels in association with a reduction in CACNA1A expression, and accumulation of abnormal insulin granules in association with SYT13 down-regulation.