energia: Electroencephalography

Evidence: 100 • authority: 72

Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the International 10–20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called "intracranial EEG". EEG is widely used both as a clinical diagnostic tool, particularly in epilepsy, and as a research tool in neuroscience. Clinical interpretation of EEG recordings is…

Evidence: 46 • authority: 92

Cortical layer 6b mediates state-dependent changes in brain activity and effects of orexin on waking and sleep.. One of the most distinctive features of the mammalian cerebral cortex is its laminar structure. Of all cortical layers, layer 6b (L6b) is by far the least studied, despite exhibiting direct sensitivity to orexin and having widespread connectivity, suggesting an important role in regulating cortical oscillations and brain state. We performed chronic electroencephalogram (EEG) recordings in mice in which a subset of L6b neurons was conditionally 'silenced', during undisturbed conditions, after sleep deprivation (SD), and after intracerebroventricular (ICV) administration of orexin.…

Evidence: 46 • authority: 72

A brain–computer interface (BCI), sometimes called a brain–machine interface (BMI), is a system that measures brain activity and translates it into functionally useful outputs, allowing interaction with an external or internal system, most commonly a computer or robotic limb. BCIs are often directed at researching, mapping, assisting, augmenting, or repairing human cognitive or sensory-motor functions. Due to the cortical plasticity of the brain, signals from implanted prostheses can, after adaptation, be handled by the brain like natural sensor or effector channels. They are often conceptualized as a human–machine interface that skips the intermediary of moving body parts (e.g. hands or fe…

Evidence: 46 • authority: 72

Neural oscillations, or brainwaves, are rhythmic or repetitive patterns of neural activity in the central nervous system. Neural tissue can generate oscillatory activity in many ways, driven either by mechanisms within individual neurons or by interactions between neurons. In individual neurons, oscillations can appear either as oscillations in membrane potential or as rhythmic patterns of action potentials, which then produce oscillatory activation of post-synaptic neurons. At the level of neural ensembles, synchronized activity of large numbers of neurons can give rise to macroscopic oscillations, which can be observed in an electroencephalogram. Oscillatory activity in groups of neurons…

Evidence: 40 • authority: 80

Low-density EEG for Source Activity Reconstruction using Partial Brain Models

Evidence: 40 • authority: 80

Low-density EEG for Source Activity Reconstruction using Partial Brain Models

Evidence: 40 • authority: 92

Glial syncytial control fields and the low-frequency resonome of the human brain.. The low-frequency resonome of the human brain, understood as the structured hierarchy of infra-slow, delta, and theta electromagnetic field organization across approximately 0.1-8 Hz, is central to large-scale neural coordination, state transitions, sleep-wake dynamics, predictive regulation, and conscious access. Existing theories explain many aspects of these phenomena through neuronal synchronization, structural connectivity, neural-field dynamics, and recurrent cortical loops. Yet the brain also appears to require slow, spatially extended control variables integrating activity across seconds, centimeters,…

Evidence: 40 • authority: 72

The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for special senses such as vision, hearing, and olfaction. Being the most specialized organ, it is responsible for receiving information from the sensory nervous system, processing that information (thought, cognition, and intelligence) and the coordination of motor control (muscle activity) and the endocrine system. While invertebrate brains arise from paired segmental ganglia (each of which is only responsible for the respective body segment) of the ventral nerve cord,…

Evidence: 35 • authority: 80

The Influences of Impressed Electrical Fields at EEG Frequencies on Brain and Behavior

Evidence: 35 • authority: 72

The human brain is the central organ of the nervous system, and with the spinal cord, comprises the central nervous system. It consists of the cerebrum, the brainstem and the cerebellum. The brain controls most of the activities of the body, processing, integrating, and coordinating the information it receives from the sensory nervous system. The brain integrates sensory information and coordinates instructions sent to the rest of the body. The cerebrum, the largest part of the human brain, consists of two cerebral hemispheres. Each hemisphere has an inner core composed of white matter, and an outer surface – the cerebral cortex – composed of grey matter. The cortex has an outer layer, the…

Evidence: — • authority: 92

Cerebellar Electrical Activity as a Marker for Predicting Brain Health and Disease: A Review.. The cerebellum is traditionally considered a structure responsible for motor control, but it is also involved in auditory perception, vocalization, speech, memory, emotional control, and social cognition. Due to its high intrinsic synaptic plasticity and complex connectivity with other brain regions, it is of potential interest for monitoring adaptive responses under various physiological and pathological conditions to capture global brain dynamics. Nevertheless, the use of electrocerebellography (ECeG) to detect changes in cerebellar electrical activity is limited, and a systematic evaluation of…

Evidence: — • authority: 90

High-frequency brain activity and muscle artifacts in MEG/EEG: a review and recommendations. In recent years high-frequency brain activity in the gamma-frequency band (30-80 Hz) and above has become the focus of a growing body of work in MEG/EEG research. Unfortunately, high-frequency neural activity overlaps entirely with the spectral bandwidth of muscle activity (~20-300 Hz). It is becoming appreciated that artifacts of muscle activity may contaminate a number of non-invasive reports of high-frequency activity. In this review, the spectral, spatial, and temporal characteristics of muscle artifacts are compared with those described (so far) for high-frequency neural activity. In addition,…