alpha wave

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alpha wave

physiology

Also known as: alpha oscillation, alpha rhythm

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June 18, 2026

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Alpha waves are electrical rhythms of the brain with a frequency of approximately 8 to 13 cycles per second. These waves are often associated with a state of wakeful relaxation. They are a type of neural oscillation, which are synchronized rhythmic patterns of electrical activity produced by neurons in the brain.12

Electroencephalography (EEG) is a technique used to record and interpret this electrical activity. In a relaxed, conscious adult, the EEG typically shows regular, oscillating waves known as alpha waves. When a person becomes alert or startled, these alpha waves are replaced by faster, irregular waves. Alpha rhythms are most prominent in the back of the brain when the eyes are closed and the mind is relatively at rest.34

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human behaviour
Central nervous system processing
The dominant rhythm is the alpha wave, which reaches its maximum frequency in adolescence and begins to slow gradually after young adulthood. This slowing may be related to disease processes (particularly vascular disease) and to basic aging processes. The older adult’s central nervous system appears to be in a state…
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The dominant rhythm is the alpha wave, which reaches its maximum frequency in adolescence and begins to slow gradually after young adulthood. This slowing may be related to disease processes (particularly vascular disease) and to basic aging processes. The older adult’s central nervous system appears to be in a state…
Read More

attention
Electrical changes
…the inhibition (blocking) of so-called alpha rhythms, usually when the eyes are opened or when the person is thinking about a task, especially one involving visual imagery. Alpha rhythms, or waves, are more or less regular electric oscillations at a frequency of about 10 cycles per second (hertz), seen principally…
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…the inhibition (blocking) of so-called alpha rhythms, usually when the eyes are opened or when the person is thinking about a task, especially one involving visual imagery. Alpha rhythms, or waves, are more or less regular electric oscillations at a frequency of about 10 cycles per second (hertz), seen principally…
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neural oscillation
Types of brain rhythms
Alpha oscillations (8–12 Hz) are most prominent above the occipital cortical area when the eyes are closed. Large-amplitude theta oscillations (4–10 Hz) dominate the hippocampal-entorhinal system during spatial navigation and memory processing. Delta waves (0.5–1.5 Hz), the largest-amplitude waves in the neocortex (the cerebral cortex…
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Alpha oscillations (8–12 Hz) are most prominent above the occipital cortical area when the eyes are closed. Large-amplitude theta oscillations (4–10 Hz) dominate the hippocampal-entorhinal system during spatial navigation and memory processing. Delta waves (0.5–1.5 Hz), the largest-amplitude waves in the neocortex (the cerebral cortex…
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biofeedback
“Alpha (wave) training” elicits the calming and integrative effects of meditation. Theta wave training has led to more focused attention, the control of “mental blocks” during examinations, and the control of anxiety.
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“Alpha (wave) training” elicits the calming and integrative effects of meditation. Theta wave training has led to more focused attention, the control of “mental blocks” during examinations, and the control of anxiety.
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electroencephalography
…recurring oscillating waves known as alpha waves. When a person is excited or startled, the alpha waves are replaced by low-voltage rapid irregular waves. During sleep, the brain waves become extremely slow. Such is also the case when a person is in a deep coma. Other abnormal conditions are associated…
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…recurring oscillating waves known as alpha waves. When a person is excited or startled, the alpha waves are replaced by low-voltage rapid irregular waves. During sleep, the brain waves become extremely slow. Such is also the case when a person is in a deep coma. Other abnormal conditions are associated…
Read More