Isochronic Tones

Isochronic tones work by emitting sound at regular intervals: the intensity of the sound goes almost directly from 0 to 100 and back again in an evenly-spaced manner. Widely regarded as the most effective tone-based method, isochronic beats produce very strong cortical responses in the brain.

Brain Waves (brainwaves) Entrainment

Brainwaves are electrical activity patterns caused by the neurons of the brain communicating with each other. Brainwaves can be detected using sensitive medical equipment such as an EEG. They provide an indication of the mental state of an individual.

Brainwaves are divided into four main categories: the Delta waves, when deep sleep occurs; the Theta waves, associated with a state of somnolence and reduced consciousness; the Alpha waves, when we are in a state of physical and mental relaxation; and the Beta waves, emitted when we are consciously alert, or when we feel agitated or tense.

Brainwave frequencies are in the range of 0.1 to 4 (Delta), 4 to 7 (Theta), 7 to 13 (Alpha) and 13 to 30 (Beta) cycles per second (Hz).

Brainwave entrainement (or synchronization), aims to cause our brainwave frequencies to fall into step with a periodic stimulus having a frequency corresponding to the intended brain-state. This can be used, for example, to induce sleep. This page uses isochronic tones as auditory stimuli.