Binaural · Isochronic
Binaural beats need headphones. Isochronic tones do not.
You put the headphones on. The left ear gets one tone, and the right ear gets a different one.
You can still use the tracks. I am not telling you to throw them out. People search binaural vs isochronic because they bought a file and want to know which one they have, and whether they need the headphones.
What is a binaural beat?
Gerald Oster wrote this up in Scientific American in 1973. You play one tone in the left ear and a slightly different tone in the right ear. Your brain hears a third pulse at the difference. Nobody is playing that pulse in the room.
Say the left ear is 400 Hz and the right ear is 440 Hz. The pulse you hear is 40 Hz. Oster found this worked best when the two tones were near 440 Hz. It faded once they got above about 1,000 Hz. You need headphones so the two ears stay apart.
What is an isochronic tone?
An isochronic tone is one tone that turns on and off. The pulse is in the air. You can play it on a speaker. You can play it on headphones too. The ears do not have to hear two different notes.
Leila Chaieb and her group wrote about this in 2015. A pulse in the air hits the ear first. You hear the binaural beat later, inside the head. When they looked at MEG work by Draganova, the physical pulse made a response about five times larger.
Do you need headphones?
Yes for binaural. No for isochronic. If you take the headphones off and play two different tones through one speaker, the air mixes them before they reach you. That is not a binaural beat anymore.
What did the studies find?
Ruth Ingendoh and her group reviewed 14 EEG studies in 2023. Five supported a brain-wave change. Eight did not. One was mixed. The tones they used were under 1,000 Hz, and the difference was about 1 to 30 Hz.
Miguel Garcia-Argibay and his group looked at 22 studies. Across those studies, binaural beats had a modest effect on thinking, anxiety, and pain. It depended on the frequency, how long people listened, and when they listened. Nobody showed an IQ jump.
The 40 Hz lab work on mice used trains of tones, not a classic binaural pair. I wrote about that 40 Hz work.
Which one should you use?
If you have headphones and you want the two-ear version, use a binaural track. If you want the pulse on a speaker, use isochronic.
If you want a short headphone listen, I send people to Genius Song. I am an affiliate, so I get a commission if you buy through that link.
Stay until the track ends. Write a number from 1 to 10 before you press play if you want one. Write it again when it ends.
Use headphones for binaural.
Use a speaker if you want isochronic.
Sources
Oster, G. “Auditory beats in the brain.” Scientific American 229(4):94-102 (1973). Two tones, one per ear, a third modulation at the difference, a carrier best near 440 Hz that vanishes above about 1,000 Hz, and headphones required (PMID 4727697). doi.org/10.1038/scientificamerican1073-94
Chaieb, L., Wilpert, E.C., Reber, T.P., & Fell, J. “Auditory beat stimulation and its effects on cognition and mood states.” Frontiers in Psychiatry 6:70 (2015). Monaural is physical AM at the periphery, binaural is built at the superior olive, and Draganova MEG found the monaural ASSR about five times the binaural. doi.org/10.3389/fpsyt.2015.00070
Ingendoh, R.M., Posny, E.S., & Heine, A. “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.” PLoS ONE 18(5):e0286023 (2023). Fourteen EEG studies: five support, eight contradict, one mixed, with carriers under 1 kHz and a difference about 1 to 30 Hz. doi.org/10.1371/journal.pone.0286023
Garcia-Argibay, M., Santed, M.A., & Reales, J.M. “Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis.” Psychological Research 83:357-372 (2019). Twenty-two studies and 35 effect sizes gave overall g = 0.45 for cognition, anxiety, and pain, with direction depending on frequency, duration, and timing, and no IQ promise. doi.org/10.1007/s00426-018-1066-8
Martorell, A.J. et al. “Multi-sensory Gamma Stimulation Ameliorates Alzheimer’s-Associated Pathology and Improves Cognition.” Cell (2019). Auditory GENUS used trains of tones at 40 Hz, not classic binaural pairs, and the dose is on the 40Hz page. doi.org/10.1016/j.cell.2019.02.014