Search results for "NEUROSCIENCE"

2020

Introduction Adolescents have experienced decreased aerobic fitness levels and insufficient physical activity levels over the past decades. While both physical activity and aerobic fitness are related to physical and mental health, little is known concerning how they manifest in the brain during this stage of development, characterized by significant physical and psychosocial changes. The aim of the study is to examine the associations between both physical activity and aerobic fitness with brains' functional connectivity. Methods Here, we examined how physical activity and aerobic fitness are associated with local and interhemispheric functional connectivity of the adolescent brain (n = 59…

2021

Abstract Reliable paradigms and imaging measures of individual-level brain activity are paramount when reaching from group-level research studies to clinical assessment of individual patients. Magnetoencephalography (MEG) provides a direct, non-invasive measure of cortical processing with high spatiotemporal accuracy, and is thus well suited for assessment of functional brain damage in patients with language difficulties. This MEG study aimed to identify, in a delayed picture naming paradigm, source-localized evoked activity and modulations of cortical oscillations that show high test–retest reliability across measurement days in healthy individuals, demonstrating their applicability in cli…

Interaction between muscle stiffness and stretch reflex sensitivity after long-term stretch-shortening cycle exercise

1998

The short latency stretch-reflex component (M1) and its interactions with muscle stiffness and with muscle performance were investigated before and after long-term stretch-shortening cycle (SSC) exercise. Dramatic fatigue induced reduction in maximal SSC performance capability, and electromyographic activity was accompanied by a consistent decrease in the M1 reflex component and eccentric peak stiffness of the muscle. It can be suggested, therefore, that the decreased muscle performance is not simply a direct effect of central or peripheral fatigue, but is partly due to impairment of the ability to utilize stiffness-related elastic energy.

Mild cognitive impairment: classification method and procedure

2012

Title: Mild cognitive impairment: classification method and procedure. Abstract: Mild cognitive impairment (MCI) is one of the most important clinical entities in the field of cognitive neuroscience, the size of their numbers and the possible evolution of some of the subtypes of dementia. The aim of this study is to test a method and procedure for classification of MCI in terms of neuropsychological test scores and its convergence with established clinical criteria, and analyze the differences between the resulting groups. After applying the inclusion-exclusion criteria, was as- sessed using a battery of neuropsychological tests to 39 people aged be- tween 60 and 89 years. Diagnostic groups…

2020

Interruptions (interfering stimuli to respond to) and distractions (interfering stimuli to be ignored) have been shown to negatively impact performance, particularly in tasks requiring working memory (WM). This study investigated how these two types of external interference affect task performance and attentional and WM processes as indexed by specific event-related potentials (ERPs) of the EEG. A Continuous Number Task (CNT) was applied, in which participants had to either decide whether the current number (condition without WM load) or the sum of the current and the preceding number (condition with WM load) was odd or even while responding to interlaced single letters (interruptions) or i…

Clinical significance of the quantitative and qualitative determination of the cerebral blood flow through the use of isotopes

1966

Es wird über die bisher entwickelten Methoden zur bestimmung der Hirndurchblutung mit radioaktiven Isotopen berichtet, wobei die quantitativen Untersuchungsmethoden hinsichtlich ihrer klinischen Bedeutung den qualitativen gegenübergestellt werden. Während die quantitativen Methoden eine genaue Bestimmung des cerebralen Blutvolumens und damit der Gesamtdurchblutung des Hirns bzw. bestimmter Hirnareale ermöglichen, bieten die qualitativen Untersuchungsmethoden hinsichtlich der klinisch-diagnostischen Aussagekraft besondere Vorteile. Aus der Bestimmung der Zirkulationszeit des Hirns und dem Verlauf der über beiden Hemisphären registrierten Aktivitätskurven lassen sich differenzial-diagnostisch…

Sleep restriction for the duration of a work week impairs multitasking performance

2010

It is important to develop shift schedules that minimise the chance for sleep-related human error in safety-critical domains. Experimental data on the effects of sleep restriction (SR) play a key role in this development work. In order to provide such data, we conducted an experiment in which cognitively demanding and long-duration task performance, simulating task performance at work, was measured under SR and following recovery. Twenty healthy male volunteers, aged 19-29 years, participated in the study. Thirteen of them had first two baseline days (8-h sleep opportunity per day), then five SR days (4-h sleep) and finally two recovery days (8-h sleep). Seven controls were allowed to sleep…

Choroidal filling pattern during a hypotensive crisis

1987

Observation d'une jeune femme de 18 ans atteinte de dystrophie progressive des cones et bâtonnets et ayant presente une crise d'hypotension arterielle au cours d'une angiographie fluoresceinique

Early developmental alterations of low-Mg2+ -induced epileptiform activity in the intact corticohippocampal formation of the newborn mouse in vitro.

2005

Abstract The generation, propagation and pharmacological properties of low-Mg 2+ -induced epileptiform activity were examined in the intact corticohippocampal formation (CHF) of the newborn (P0–4) mouse in vitro. Multi-site field potential recordings in dentate gyrus (DG), CA3, CA1, entorhinal cortex (EC) and temporal cortex (TC) revealed in 0.2 mM Mg 2+ -containing ACSF a stable pattern of spontaneous epileptiform activity consisting of recurrent ictal-like events (ILEs) and interictal events (IEs). Although this activity could be consistently observed as early as P0, ILEs were smaller in amplitude, less frequent and showed a slower onset in P0–2 as compared to P3–4 animals. In all age gro…

From structural biochemistry to expression profiling: Neuroprotective activities of estrogen

2005

Abstract Estrogens are neuromodulatory and neuroprotective hormones. Chemically, estrogens are steroid compounds and unfold most of their activities through the activation of nuclear receptors that bind to specific target genes and control their transcription. Two subtypes of estrogen receptors are known (estrogen receptor α and estrogen receptor β) and they are expressed throughout the body including the CNS and in particular the brain. We employed large scale DNA-chip-analysis to display the gene expression pattern differentially regulated by both estrogen receptor subtypes in human neuronal cells. We identified different gene families regulated by estrogen receptors that complement the k…