In this study, the spatial and temporal frequency tuning characteristics of the MEG gamma (40-60 Hz) rhythm and the BOLD response in primary visual cortex were measured and compared. In an identical MEG/fMRI paradigm, 10 participants viewed reversing square wave gratings at 2 spatial frequencies [0.5 and 3 cycles per degree (cpd)] reversing at 5 temporal frequencies (0, 1 6, 10, 15 Hz). Three-d...

The enzyme excretion of dipeptidylpeptidase IV (EC 3.4.14.5), gamma-glutamyltransferase (EC 2.3.2.2), and alanine aminopeptidase (EC 3.4.11) was pursued in three different age groups of female volunteers over a period of 70 days. The first group (1-3 years: n = 6) consisted of girls living in a children's home, the second (26-50 years, n = 7) of medical staff and the third (65-87 years, n = 7) ...

Respiratory sinus arrhythmia (RSA) is generally known as the autonomically mediated modulation of the sinus node pacemaker frequency in synchrony with respiration. Cardiorespiratory interactions have been largely investigated during sinus rhythm, whereas little is known about interactions during reentrant arrhythmias. In this study, cardiorespiratory interactions at the atrial and ventricular l...

Recent hypotheses on the potential role of neuronal oscillations in speech perception propose that speech is processed on multi-scale temporal analysis windows formed by a cascade of neuronal oscillators locked to the input pseudo-rhythm. In particular, Ghitza (2011) proposed that the oscillators are in the theta, beta, and gamma frequency bands with the theta oscillator the master, tracking th...

This study aimed to evaluate the long term memory through electroencephalographic techniques. Were evaluated, in individuals from human and exact sciences groups, during following cognitive activities: task: 1 – MEMORIZING WORDS; 2 REMEMBER THE WORDS OF ACTIVITY 1; 3 FIGURES; 4 FIGURES 3. The gamma rhythm was recorded electroencephalogram (EEG), according 10-20 system. Thus, tasks analyze capac...

Fast (gamma) oscillations in the cortex underlie the rapid temporal coordination of large-scale neuronal assemblies in the processing of sensory stimuli. Cortical gamma rhythm is modulated in vivo by cholinergic innervation from the basal forebrain and can be generated in vitro after exogenous cholinergic stimulation. Using the isolated guinea pig brain, an in vitro preparation that allows for ...

results linear mixed model analyses showed that athletes slept on average 43 minutes longer when they slept during usual (night) times than during abnormal (day) times. in general, sleep duration decreased during the race with on average 18 minutes per period. conclusions this pilot study shows that, even under extreme violation of sleep hygiene rules, there still is an apparent effect of circa...

Current evidence suggests that delta oscillations (0.5-4 Hz) in the brain are generated by intrinsic network mechanisms involving cortical and thalamic circuits. Here we report that delta band oscillation in spike and local field potential (LFP) activity in the whisker barrel cortex of awake mice is phase locked to respiration. Furthermore, LFP oscillations in the gamma frequency band (30-80 Hz...

Many environmental stimuli present a quasi-rhythmic structure at different timescales that the brain needs to decompose and integrate. Cortical oscillations have been proposed as instruments of sensory de-multiplexing, i.e., the parallel processing of different frequency streams in sensory signals. Yet their causal role in such a process has never been demonstrated. Here, we used a neural micro...