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{{dablink|For the 3D platform video game, see [[Alpha Waves]].}}

[[Image:eeg_alpha.svg|thumb|Alpha waves |400px|right]]
'''Alpha waves''' are [[electromagnetic]] oscillations in the frequency range of 8–12 [[Hertz|Hz]] arising from ''synchronous'' and ''coherent'' (''in phase'' / ''constructive'') electrical activity of [[Human thalamus|thalamic]] pacemaker cells in the [[human brain]]. They are also called [[Hans Berger|Berger]]'s wave in memory of the founder of EEG {{Harv|Brazier|1970}}.

''Alpha waves'' are one type of [[brain waves]], commonly detected by [[electroencephalography]] (EEG) or [[magnetoencephalography]] (MEG) and predominantly found to originate from the [[occipital lobe]] during periods of waking relaxation with the eyes closed. 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. Occipital alpha waves during periods of eyes closed are the strongest brain signals of the EEG. They usually can be detected with the naked eye.

An alpha-like normal variant called [[Mu rhythm|mu (μ)]] is sometimes seen over the motor cortex (central scalp) and attenuates with movement, or even with the intention to move.

Research conducted by the Transcendental Meditation (TM) Program and the Maharishi State University indicates that alpha waves are involved in a fourth unique state of consciousness (besides waking, dreaming, and sleeping). The researchers say this state is fundamental to the other three states of consciousness. In particular, the researchers found this state of consciousness to be most active during meditation. It is called self-referral consciousness, or consciousness that is aware of itself, rather than some outside object. Researchers have infered that this kind of consciousness is characteristic of the alpha waveform itself.

Alpha waves also happen to be the main waveform that is of long-range conductance in the human brain. That is to say that the various tissues of the brain function most coherently in this mode. Hence, the proponents of TM advocate it as a means of increasing long-range integration of the brain and mental health.⏎
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==See also==
* [[Electroencephalography]]
* [[Sensorimotor rhythm|SMR]] (Sensory Motor Rhythm)
* [[Sensory Integration Dysfunction]]
* [[Holonomic brain theory]]
* [[Epilepsy]]
* [[Sleep]]
* [[Mu wave]]
* [[Beta wave]]
* [[Delta wave]]
* [[Gamma wave]] 
* [[Theta wave]]
* [[Theanine]]

== References ==

* {{Harvard reference | Surname = Brazier | Given = M. A. B. | Title = The Electrical Activity of the Nervous System | Year = 1970 | Publisher = Pitman | Place = London}}


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[[Category:Medical tests]]
[[Category:Meditation]]
[[Category:Electroencephalography]]

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