Intracranial EEG power spectra and phase synchrony during consciousness and unconsciousness.

Conscious Cogn

Department of Physics, University of Auckland, Private Bag 92019, Auckland, New Zealand.

Published: December 2009

AI Article Synopsis

Article Abstract

Power density spectra and phase synchrony measurements were taken from intracranial electrode grids implanted in epileptic subjects. Comparisons were made between data from the waking state and from the period of unconsciousness immediately following a generalised tonic-clonic seizure. Power spectra in the waking state resembled coloured noise. Power spectra in the unconscious state resembled coloured noise from 1 to about 5 Hz, but at higher frequencies changed in two out of three subjects to resemble white noise. This boosted unconscious gamma power to a higher level than conscious gamma power. For both gamma and beta passbands, synchrony measurements showed more widespread phase synchrony in the unconscious than the conscious state. We conclude that neither gamma activity per se nor phase synchrony per se are neural correlates of consciousness.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.concog.2009.08.010DOI Listing

Publication Analysis

Top Keywords

phase synchrony
16
power spectra
12
spectra phase
8
synchrony measurements
8
waking state
8
state resembled
8
resembled coloured
8
coloured noise
8
gamma power
8
power
6

Similar Publications

Circadian clocks in the body drive daily cycles in physiology and behavior. A master clock in the brain maintains synchrony with the environmental day-night cycle and uses internal signals to keep clocks in other tissues aligned. Work in cell cultures uncovered cyclic changes in tissue oxygenation that may serve to reset and synchronize circadian clocks.

View Article and Find Full Text PDF

Transcranial alternating current stimulation (tACS) at 5-Hz to the right hemisphere can alleviate anxiety symptoms. We aimed to explore the connectivity changes following the treatment. We collected electroencephalography (EEG) data from 24 participants with anxiety disorders before and after the tACS treatment during a single session.

View Article and Find Full Text PDF

Cardiovascular health requires the orchestration of the daily rhythm of blood pressure (BP), which responds to changes in light exposure and dietary patterns. Whether rhythmic light and feeding can modulate daily BP rhythm directly or via modulating intrinsic core clock gene is unknown. Using inducible global knockout mice (iBmal1KO), we explored the impact of rhythmic light, rhythmic feeding, or their combination on various physiological parameters.

View Article and Find Full Text PDF

Multi-level cognitive state classification of learners using complex brain networks and interpretable machine learning.

Cogn Neurodyn

December 2025

National Engineering Research Center of Educational Big Data, Central China Normal University, Luoyu Road, Wuhan, 430079 Hubei China.

Identifying the cognitive state can help educators understand the evolving thought processes of learners, and it is important in promoting the development of higher-order thinking skills (HOTS). Cognitive neuroscience research identifies cognitive states by designing experimental tasks and recording electroencephalography (EEG) signals during task performance. However, most of the previous studies primarily concentrated on extracting features from individual channels in single-type tasks, ignoring the interconnection across channels.

View Article and Find Full Text PDF

Perception and production of music and speech rely on auditory-motor coupling, a mechanism which has been linked to temporally precise oscillatory coupling between auditory and motor regions of the human brain, particularly in the beta frequency band. Recently, brain imaging studies using magnetoencephalography (MEG) have also shown that accurate auditory temporal predictions specifically depend on phase coherence between auditory and motor cortical regions. However, it is not yet clear whether this tight oscillatory phase coupling is an intrinsic feature of the auditory-motor loop, or whether it is only elicited by task demands.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!