Search results for "DEP"

Special Features of the Hippocampal Formation with Respect to Seizure Conditions

1987

The hippocampus has long been known as a region particularly prone to epileptiform discharges (Kandel et al. 1961). Connections and physiology of this archaic cortical structure are relatively well charac-terized and a wealth of information on features favoring exaggerated neuronal activity has emerged in recent years. The lamellar organization of the hippo-campus (Andersen et al. 1971) may be one of these features; it certainly has facilitated their investigation. Tissue slices cut along the lamellae, perpendicular to the axis of the structure, contain a relatively undisturbed chain of neurons which can be rigorously investigated in vitro. The results from such experiments have allowed mod…

Cell Cycle: The Life Cycle of a Cell

2013

“Where a cell arises, there must be a previous cell”. This early statement of Rudolf Virchow already points to the process that is called cell cycle. It describes a series of events leading to cell division and duplication and can be sectioned into phases that are controlled by a collection of proteins interacting with each other, the cyclines and the cycline-dependent kinases. It is mandatory that DNA replication is conservative meaning that its structure and sequence remain unaltered while the DNA is duplicated before the cell actually divides. Checkpoints are responsible for the supervision, proteins such as p53 and RB being the key protagonists in cell cycle control. Upon DNA damage rec…

Comparative assessment of brain activity during depth perception of stereoscopic and volumetric images

2020

Recent advancements in visualization systems have triggered a growing demand for the objective and accurate comparison of user cognitive requirements when perceiving three-dimensional images demonstrated in different ways. In this work, we present the first comparative assessment of brain activity in subjects viewing stereoscopic images and volumetric images. Electroencephalography was employed to assess the short-term changes in event related potentials and neural oscillations which were further interpreted in terms of cognitive requirements for relative depth judgments. As a result, considerably higher activity have been registered in the beta band and gamma band in case of judging relati…

Proton magnetic resonance imaging with para-hydrogen induced polarization.

2012

A major challenge in imaging is the detection of small amounts of molecules of interest. In the case of magnetic resonance imaging (MRI) their signals are typically concealed by the large background signal of e.g. the body. This problem can be tackled by hyperpolarization which increases the NMR signals up to several orders of magnitude. However, this strategy is limited for (1)H, the most widely used nucleus in NMR and MRI, because the enormous number of protons in the body screens the small amount of hyperpolarized ones. Here, we describe a method giving rise to high (1)H MRI contrast for hyperpolarized molecules against a large background signal. The contrast is based on the J-coupling i…

Exploring Frequency-dependent Brain Networks from ongoing EEG using Spatial ICA during music listening

2019

AbstractRecently, exploring brain activity based on functional networks during naturalistic stimuli especially music and video represents an attractive challenge because of the low signal-to-noise ratio in collected brain data. Although most efforts focusing on exploring the listening brain have been made through functional magnetic resonance imaging (fMRI), sensor-level electro- or magnetoencephalography (EEG/MEG) technique, little is known about how neural rhythms are involved in the brain network activity under naturalistic stimuli. This study exploited cortical oscillations through analysis of ongoing EEG and musical feature during free-listening to music. We used a data-driven method t…

Neuropsychological profiles of FMR-1 premutation and full-mutation carrier females

1999

Abstract The present French–German investigation of fragile-X syndrome (fra-X) was undertaken to disentangle genetic from environmental effects on cognitive performance as assessed with the following measures: Wechsler Adult Intelligence Scale-Revised (WAIS-R), Wisconsin Card Sorting Test, Trail-Making Test, Tower of Hanai, Verbal Fluency Test, Stroop Test, short-term and consolidation memory, and the d2 task. Groups with different genotypes ( n =11 mothers with a full mutation in the FMR-1 gene of fra-X children; n =65 mothers with a premutation in the FMR-1 gene of fra-X children; n =18 siblings of these mothers with normal CGG repeats) and with different psychosocial stressors from fra-X…

Letters to the editor

1992

Individual Independent Component Analysis on EEG: Event-Related Responses Vs. Difference Wave of Deviant and Standard Responses

2016

Independent component analysis (ICA) is often used to spatially filter event-related potentials (ERPs). When an oddball paradigm is applied to elicit ERPs, difference wave (DW, responses of deviant stimuli minus those of standard ones) is often used to remove the common responses between the deviant and the standard. Thus, DW can be produced first, and then ICA is used to decompose the DW. Or, ICA is performed on responses of the deviant and standard stimuli separately, and then DW is applied on the filtered responses. In this study, we compared the two approaches to analyzing mismatch negativity (MMN). We found that DW introduced noise in the time and space domains, resulting in more diffi…

Obstructive sleep apnea is an independent predictor for dyslipidemia: Data from the European Sleep Apnea Database (ESADA)

2017

Background and aim: Obstructive sleep apnea (OSA) and dyslipidemia are both independently well-recognized risk factors for cardiovascular disease. Previous data are inconclusive regarding the relationship between OSA and dyslipidemia. The aim of the present study was to investigate the association between OSA and dyslipidemia in ESADA (European Sleep Apnea Database). Methods: The cross-sectional analysis included 8592 patients (age 50.1±12.7 years, 69.1% male, BMI 30.8±6.6 kg/m2, mean AHI 25.7±25.9 n/h) from the ESADA. The independent relationship between measures of OSA (AHI, ODI, mean and lowest saturation) and lipid profile (total cholesterol [TC], HDL-cholesterol [HDL-C] (n=3289) and fa…

Alpha-Synchronized Stimulation of the Dorsolateral Prefrontal Cortex (DLPFC) in Major Depression: A Proof-of-Principle EEG-TMS Study

2018

High-frequency repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) shows therapeutic potential in pharmaco-resistant patients with major depression. However, clinical efficacy is limited by high inter-individual variability and low response rates. One possible strategy to improve the effect size and consistency may be brain state dependent brain stimulation, i.e. coupling of TMS pulses to the endogenous brain states as reflected by the instantaneous oscillatory brain activity. Here we present findings from a proof-of-principle study of alpha-oscillation synchronized brain stimulation of the frontal cortex in patients with major depression (…