delta wave

physiology

Also known as: delta oscillation, delta-wave

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Last updated

June 25, 2026

Quick Summary

Delta waves are high-amplitude, low-frequency (less than four cycles per second) electrical rhythms of the brain. They are most prominent in infancy and early childhood and occur especially during slow-wave sleep (N3 stage). This stage of sleep is the deepest and most restorative, characterized by maximum muscle relaxation and a low heart rate.12

Abnormal delta wave activity can be associated with various conditions, including traumatic brain injury, dementia, and localized areas of brain damage. Electroencephalography (EEG) is a technique used to record and interpret these brain-wave patterns.13

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electroencephalography
…irregular slow waves known as delta waves arise from the vicinity of a localized area of brain damage.
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…irregular slow waves known as delta waves arise from the vicinity of a localized area of brain damage.
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neural oscillation
Types of brain rhythms
Delta waves (0.5–1.5 Hz), the largest-amplitude waves in the neocortex (the cerebral cortex region associated with sight and hearing), are present during non-REM sleep. Beta rhythms (13–30 Hz) are present throughout the motor system in the absence of movement, while transient beta oscillations (or sleep…
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Delta waves (0.5–1.5 Hz), the largest-amplitude waves in the neocortex (the cerebral cortex region associated with sight and hearing), are present during non-REM sleep. Beta rhythms (13–30 Hz) are present throughout the motor system in the absence of movement, while transient beta oscillations (or sleep…
Read More