Notes to Future-Me

Brainwave Entrainment

Posted:2024-02-15
Tags:Brain

It has been observed

Brainwave entrainment is the name for the observed phenomena that large-scale brainwave oscillations (“brianwaves”) will synchronize with rhythmic external stimulii (flashing lights or pulsing audio).

There is a hypothesis that this effect can be used to modify cognitive function, but is there any evidence for it?

Actionable Takeaways

There is some evidence for the effectiveness of brainwave entrainment. The evidence is mixed (but generally positive) and shows no real negative side-effects.

Since binaural and isochronic beats are widely available for no cost, anyone interested in it should try several to see if they experience benefits.

When attempting brainwave entrainment, begin exposure to the rhythmic stimuli BEFORE beginning the task and continue the stimuli while working on the task1.

Defining Terms

“Brainwaves” are a just a crude measure of the rate of individual neuron activations over time. Brainwaves do not give a clear indication that , other than there is a large amount of individual neurons firing at the same time.

Simulation of Neural Oscillations

Isochronal (or isochronic) tones are audio tones with a constant, regular beat. From the Greek, “iso-chronal” being “equal-time”.

Monaural beats are regular audio beats. Binaural beats play a slightly different audio tone into each ear, and the percieved difference between the two frequencies is the important thing.

The Research

Several meta-analyses have been done on the topic23145, most focus on binaural beats2345.

  1. A comprehensive review of the psychological effects of brainwave entrainment Meta-analysis, any form of rhythmic stimuli. ↩ ↩2

  2. Binaural beats to entrain the brain? A systematic review of the effects of binaural beat stimulation on brain oscillatory activity, and the implications for psychological research and intervention Meta-analysis, focused on binaural beats. Fourteen studies met inclusion criteria: five reported positive results, eight negative results, and one with mixed results. ↩ ↩2

  3. Potential of binaural beats intervention for improving memory and attention: insights from meta-analysis and systematic review Meta-analysis, focused on binaural beats. ↩ ↩2

  4. Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis Meta-analysis, focused on binaural beats. Twenty-two studies met inclusion criteria. Findings suggest that binaural-beat exposure “before” and “before and during” a task produces superior results than exposure “during” the task. ↩ ↩2

  5. Auditory Beat Stimulation and its Effects on Cognition and Mood States Meta-analysis. Covers monaural and binaural beats, with a focus on binaural. Thirty studies met inclusion criteria. ↩ ↩2