(Redirected from Alpha waves)
'Alpha waves' are
electromagnetic oscillations in the frequency range of 8–12
Hz arising from ''synchronous'' and ''coherent'' (''in phase'' / ''constructive'') electrical activity of
thalamic pacemaker cells in the
human brain. They are also called
Berger's wave in memory of the founder of EEG.
''Alpha waves'' are commonly detected by
electroencephalography (EEG) or
magnetoencephalography (MEG) and predominantly found to originate from the
occipital lobe during periods of relaxation, with eyes closed but still awake. Conversely alpha waves are attenuated with open eyes as well as by drowsiness and sleep. They are thought to represent the activity of the visual cortex in an idle state.
An alpha-like normal variant called
mu (μ) is sometimes seen over the motor cortex (central scalp) and attenuates with movement, or even with the intention to move.
References
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See also
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Electroencephalography
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SMR
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Sensory Integration Dysfunction
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Holonomic brain theory
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Epilepsy
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Sleep
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Mu wave
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Beta wave
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Delta wave
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Gamma wave
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Theta wave