Constitutive spectral EEG peaks in the gamma range: suppressed by sleep, reduced by mental activity and resistant to sensory stimulation

This Document is Protected by copyright and was first published by Frontiers. All rights reserved. it is reproduced with permission. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Objective: In a systematic study of gamma activity in neuro-psychiatric disease, we unexpectedly observed distinctive, apparently persistent, electroencephalogram (EEG) spectral peaks in the gamma range (25–100 Hz). Our objective, therefore, was to examine the incidence, distribution and some of the characteristics of these peaks. Methods: High sample-rate, 128-channel, EEG was recorded in 603 volunteers (510 with neuropsychiatric disorders, 93 controls), whilst performing cognitive tasks, and converted to power spectra. Peaks of spectral power, including in the gamma range, were determined algorithmically for all electrodes. To determine if peaks were stable, 24-h ambulatory recordings were obtained from 16 subjects with peaks. In 10 subjects, steady-state responses to stimuli at peak frequency were compared with off-peak-frequency stimulation to determine if peaks were a feature of underlying network resonances and peaks were evaluated with easy and hard versions of oddball tasks to determine if peaks might be influenced by mental effort. Results: 57% of 603 subjects exhibited peaks >2 dB above trough power at or above 25 Hz. Larger peaks (>5 dB) were present in 13% of subjects. Peaks were distributed widely over the scalp, more frequent centrally. Peaks were present through the day and were suppressed by slow-wave-sleep. Steady-state responses were the same with on- or off-peak sensory stimulation. In contrast, mental effort resulted in reductions in power and frequency of gamma peaks, although the suppression did not correlate with level of effort. Conclusions: Gamma EEG can be expressed constitutively as concentrations of power in narrow or wide frequency bands that play an, as yet, unknown role in cognitive activity. Significance: These findings expand the described range of rhythmic EEG phenomena. In particular, in addition to evoked, induced and sustained gamma band activity, gamma activity can be present constitutively in spectral peaks

Exploring the power clean

The power clean and its variations are prescribed by strength and conditioning coaches as part of the ‘big three’ to develop “total body strength”. This article explores the application of the power clean and its variations to athletic performance and introduces strength and conditioning coaches to teaching progressions, with specific emphasis on developing the correct body positioning required for the power clean. Teaching components are addressed with special reference to taller athletes. It is recommended that strength and conditioning coaches teaching the hang clean follow a progression model to decrease movement complexity when advancing athletes to the power clean

DESMOVILIZADOS ¿A QUÉ TIPO DE PROBLEMAS PSICOSOCIALES SE ENFRENTAN?

El enfrentamiento que vivió Colombia por décadas ha dejado diferentes afectados, entre estos, las víctimas directas del conflicto, como también la población que decidió abandonar las armas y reinsertarse a la vida civil. Mediante este artículo de investigación cualitativa con diseño fenomenológico e investigación-acción, se pretende comprender los problemas psicosociales a los que se ven enfrentados los desmovilizados de la localidad 19, del barrio Ciudad Bolívar, Bogotá-Colombia.Para explorar las experiencias de vida y poder plantear estrategias de apoyo, se seleccionó una muestra de 20 individuos de tipo voluntarios, utilizando como técnicas de recolección de información entrevistas semiestructuradas y grupos focales.Dentro de la revisión literaria, se encontró que, el mayor desafío de la Agencia Colombiana para la reintegración es ayudar a los desmovilizados a entrar al mercado laboral, ya que muchos de ellos, son personas sin estudios y en un gran porcentaje son analfabetas

Shared and Disorder-Specific Event-Related Brain Oscillatory Markers of Attentional Dysfunction in ADHD and Bipolar Disorder.

Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) often present with overlapping symptoms and cognitive impairments, such as increased fluctuations in attentional performance measured by increased reaction-time variability (RTV). We previously provided initial evidence of shared and distinct event-related potential (ERP) impairments in ADHD and BD in a direct electrophysiological comparison, but no study to date has compared neural mechanisms underlying attentional impairments with finer-grained brain oscillatory markers. Here, we aimed to compare the neural underpinnings of impaired attentional processes in ADHD and BD, by examining event-related brain oscillations during a reaction-time task under slow-unrewarded baseline and fast-incentive conditions. We measured cognitive performance, ERPs and brain-oscillatory modulations of power and phase variability in 20 women with ADHD, 20 women with BD (currently euthymic) and 20 control women. Compared to controls, both ADHD and BD groups showed increased RTV in the baseline condition and increased RTV, theta phase variability and lower contingent negative variation in the fast-incentive condition. Unlike controls, neither clinical group showed an improvement from the slow-unrewarded baseline to the fast-incentive condition in attentional P3 amplitude or alpha power suppression. Most impairments did not differ between the disorders, as only an adjustment in beta suppression between conditions (lower in the ADHD group) distinguished between the clinical groups. These findings suggest shared impairments in women with ADHD and BD in cognitive and neural variability, preparatory activity and inability to adjust attention allocation and activation. These overlapping impairments may represent shared neurobiological mechanisms of attentional dysfunction in ADHD and BD, and potentially underlie common symptoms in both disorders.We thank all who made this research possible: The National Adult ADHD Clinic at the South London and Maudsley Hospital, Dr Helen Costello, Prof Sophia Frangou, Prof Anne Farmer, Jessica Deadman, Hannah Collyer, Sarah-Jane Gregori, and all participants who contributed their time to the study. Dr Giorgia Michelini was supported by a 1+3 PhD studentship awarded by the MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London (G9817803). This project was supported by an Economic and Social Research Council studentship to Dr Viryanaga Kitsune (ES/100971X/1). Dr Giorgia Michelini and Prof Philip Asherson are supported by generous grants from the National Institute for Health Research Biomedical Research Centre for Mental Health at King’s College London, Institute of Psychiatry, Psychology and Neuroscience and South London and Maudsley National Health Service (NHS) Foundation Trust. The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication

Getting A Leg Up On Compartment Syndrome

The purpose of this presentation is to increase the awareness of lower leg compartment syndrome for healthcare practitioners and the general public. The two different types of compartment syndrome are acute and chronic compartment syndrome. The prevalence of chronic compartment syndrome is most common throughout the active population, yet it is important to note that acute compartment syndrome can become life threatening if misdiagnosed. Therefore, this presentation will discuss the challenges of clinically evaluating and diagnosing compartment syndrome. This presentation will include a discussion of the etiology, pathogenesis, evaluation, treatment, rehabilitation and unique components of chronic compartment syndrome. A thorough understanding, combined with the early recognition and proper care may reduce the severity of compartment syndrome and aid in the return to functional activity

Getting A Leg Up On Compartment Syndrome

The purpose of this presentation is to increase the awareness of lower leg compartment syndrome for healthcare practitioners and the general public. The two different types of compartment syndrome are acute and chronic compartment syndrome. The prevalence of chronic compartment syndrome is most common throughout the active population, yet it is important to note that acute compartment syndrome can become life threatening if misdiagnosed. Therefore, this presentation will discuss the challenges of clinically evaluating and diagnosing compartment syndrome. This presentation will include a discussion of the etiology, pathogenesis, evaluation, treatment, rehabilitation and unique components of chronic compartment syndrome. A thorough understanding, combined with the early recognition and proper care may reduce the severity of compartment syndrome and aid in the return to functional activity

National Basketball Strength and Conditioning Association (NBSCA) Performance Summit 2019 – Chicago in Review

The 2019 National Basketball Strength and Conditioning Association (NBSCA) Performance Summit (PS) was held at Palmer House Hilton, Chicago, IL, May 19, 2019. With the largest contingent of strength and conditioning coaches, athletic trainers and sports coaches in attendance to date, the 2019 NBSCA PS was well represented across the National Collegiate Athletic Association (NCAA), National Basketball Association (NBA), and NBA G-League. With several delegates representing sports outside of basketball, there was significant interest in the theme of a multi-faceted approach to strength and conditioning in the professional team setting. In conjunction with the National Strength and Conditioning Association (NSCA), this year’s event was live streamed for the first time with online participants from seven countries. This article provides a review of sessions presented at the 2019 NBSCA PS including strength and conditioning methods and coaching strategies, in-season strength programming, force plate assessment, injury prevention, and player monitoring

Surface Laplacian of scalp electrical signals and independent component analysis resolve EMG contamination of electroencephalogram

This article appeared in a journal published by Elsevier Ltd. Under Elsevier's copyright, mandated authors are not permitted to make work available in an institutional repository