Simfishy said:SO they characterize it into alpha,beta,gamma,and delta waves. Are those just different behavioral patterns of the same wave or distinct waves that can all be seen on the same diagram? There isn't a good explanation of the electroencephalography anywhere - not in my neuroscience textbook, not on Wikipedia, they only describe what different amplitudes of each means...
Brain waves are attributed to electrical activities of the brain which are manifest as alternating potential differences at the scalp surface. When acquired through scalp electrodes, such potential differences result in time-continuous signals termed electroencephalogram (EEG). From a physical point of view, it is opportune to model the wave-like qualities of EEG as a finite sum of harmonic oscillations at discrete vibration rates triggered by a central pace-maker. Hence, brain-waves can analoguously be interpreted like sound waves in acoustics which consist of a fundamental oscillation superimposed by higher harmonics. Each of these partial tones is uniquely characterized by 2 quantities, its frequency ("pitch") and its amplitude ("loudness").
In terms of this model, brain-waves are composed of a series of "partial tones" ranging in frequency between 0.25Hz and 64Hz (7 octaves), whereby the "tonal composition" essentially depends on the state of consciousness, such as wakefulness or sleep stages.
Electroencephalography, or EEG, is a non-invasive method used to record and measure the electrical activity of the brain. It involves placing electrodes on the scalp to detect and record the brain's electrical signals.
An EEG is typically performed in a quiet and dimly lit room. The patient's scalp is cleaned and small metal electrodes are attached to specific locations using a conductive gel. The electrodes are connected to a machine that records and amplifies the electrical signals from the brain.
EEG is commonly used to diagnose and monitor conditions related to brain function, such as epilepsy, sleep disorders, and brain injuries. It can also be used to study brain activity during different tasks and activities.
Yes, EEG is a safe and non-invasive procedure. The electrodes do not send any electricity into the brain, they only record the brain's electrical activity. However, people with certain medical conditions, such as a pacemaker, may need to consult with their doctor before undergoing an EEG.
The duration of an EEG can vary, but it typically takes between 30 minutes to an hour. Sometimes, longer recordings may be needed, such as during a sleep study. The patient is usually able to resume their normal activities immediately after the procedure.