By Gaelyn Lyons
Finals are just around the corner, and you’re scrambling to study for that last exam. You’re probably stressed out, having a hard time focusing, and *most likely* losing sleep. First, let’s take a deep breath. Breathe in. Breathe out. How are you feeling? Are you still stressed? Then let me tell you about binaural beats.
Binaural beats are a form of auditory beat stimulation (ABS) and auditory illusion where two different sound frequencies are introduced to each ear separately.1 These sound waves are processed in the area of the brain called the superior olivary nucleus and the resulting frequency, referred to as the beat, is the difference between the two original sound waves.1 Recently, ABS has been sought out to be used as a form of mindfulness to help improve mood and induce relaxation.2 In addition to binaural beats, monaural beats are another form of ABS used to cause cognitive responses. The difference of the two tones again produces this form of beat, however, unlike binaural beats, this frequency is objective and is heard through both ears.1,2 To summarize, monaural and binaural beats are produced by the difference between two frequencies. The difference is that monaural beats are presented simultaneously to both ears whereas the binaural beat is formed in the brain when the two different frequencies are presented to each ear separately.
The brain processes these sound waves through the auditory pathway, which involves the lemniscal and non-lemniscal pathways.3 The lemniscal pathway is the primary physical pathway that carries sound waves from the cochlea to the primary auditory complex (Figure 1).3,4 The frequencies enter the ear canal and cause vibrations in the middle and inner ear.5 An organ in the inner ear, called the organ of Corti, converts the vibrations into a neural action potential. The vestibulocochlear nerve carries the potential to the auditory processing centers in the brain, most notably the primary auditory cortex (Figure 2).4,5 The non-lemniscal pathway, also known as the reticular sensory pathway, carries the stimuli to be processed into sensory messages like emotion and attention (Figure 3).
Now that you know what binaural beats are and how the brain processes them, you’re probably thinking, “That’s a lot of neuroscience information about binaural beats. But how do they affect the brain?” I’m glad you asked.
Studies have indicated that binaural beats affect cognitive functions, including improved memory and attention.2,6,7 In addition, these beats have also been implicated in reducing anxiety levels and lowering pain perception8,9. These studies utilize electroencephalography (EEG), which involves using electrodes to detect electrical signals from the brain, to measure brain responses to different sound frequencies.10 Research has found that specific frequencies do elicit different cognitive responses.6 Delta frequencies, which range from 1-4 Hz, are associated with deeper sleep and relaxation, theta frequencies, which range from 4-8 Hz, are associated with REM sleep, reduced anxiety, and increased meditative and creative states, alpha frequency, which range from 8-13 Hz, are associated with increased positivity and reduced stress, and beta frequencies, which range from 14-30 Hz, are associated with increased concentration, alertness, problem-solving, and improved memory (Figure 4).11
Studies have also observed monaural beats to be just as effective as binaural beats with monaural gamma, theta, and alpha waves found to reduce anxiety.12 However, monaural beats need to be physically heard in order to be effective whereas binaural beats do not need to be audible.13 Since binaural beats are the perception of two sperate frequencies being processed inside the brain, they can be used to identify many different neurological issues and cognitive functions in hearing, partial-hearing, and deaf individuals.13,14
The full mechanism and effectiveness of binaural beats on brain functions are still not understood. There are conflicting scientific data in the literature about whether these beats truly affect cognitive functions or are simply a placebo.10 According to Dr. Miguel Garcia-Argibay, a psychology researcher, the main issues with the conflicting evidence are the inconsistency of the beats used and the duration in which participants are listening to them.15 While there is literature showing an effect of binaural beats on the brain, much research still needs to be done to understand the benefits of binaural beats fully.
Even though these beats haven’t been scientifically proven to affect the brain physically yet, they might be worth trying out in your next meditation or study session. YouTube provides many videos that utilize binaural beats in their music to help with sleep, stress relief, and focus. One that I use often is this one! So, in the wise words of Queen Bey herself, bring the beat in!
TL:DR
- Binaural beats are an auditory illusion that involve two different sound wave frequencies going into each ear.
- Two pathways process auditory information: the lemniscal pathway and the non-lemniscal pathway.
- Binaural beats are used as a therapeutic tool to treat anxiety, depression, and sleeplessness.
References
1. Chaieb, L., Wilpert, E. C., Reber, T. P. & Fell, J. Auditory Beat Stimulation and its Effects on Cognition and Mood States. Front. Psychiatry 6, (2015).
2. Engelbregt, H., Barmentlo, M., Keeser, D., Pogarell, O. & Deijen, J. B. Effects of binaural and monaural beat stimulation on attention and EEG. Exp. Brain Res. 239, 2781–2791 (2021).
3. Davies, K. & Sugano, Y. The Auditory Pathway – Structures of the Ear – Auditory Transduction – TeachMeAnatomy. https://teachmeanatomy.info/neuroanatomy/pathways/auditory-pathway/ (2020).
4. Pujol, R. Auditory Brain | Cochlea. http://www.cochlea.eu/en/auditory-brain.
5. Shahid, S. Auditory pathway: Anatomy, ear structures, transduction | Kenhub. https://www.kenhub.com/en/library/anatomy/auditory-pathway.
6. Basu, S. & Banerjee, B. Potential of binaural beats intervention for improving memory and attention: insights from meta-analysis and systematic review. Psychol. Res. 1–13 (2022) doi:10.1007/S00426-022-01706-7/TABLES/4.
7. Garcia-Argibay, M., Santed, M. A. & Reales, J. M. Binaural auditory beats affect long-term memory. Psychol. Res. 83, 1124–1136 (2019).
8. Garcia-Argibay, M., Santed, M. A. & Reales, J. M. Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis. Psychol. Res. 83, 357–372 (2019).
9. PLOS. Music combined with auditory beat stimulation may reduce anxiety for some: Combined treatments appear to help people with moderate trait anxiety better than music alone. ScienceDaily https://www.sciencedaily.com/releases/2022/03/220309140921.htm (2022).
10. Dabrowski, J. Binaural beats: a useful tool or another wellness fad? | Varsity. https://www.varsity.co.uk/science/23517.
11. Cafasso, J. Binaural Beats: Sleep, Therapy, and Meditation. https://www.healthline.com/health/binaural-beats.
12. Chaieb, L., Wilpert, E. C., Hoppe, C., Axmacher, N. & Fell, J. The Impact of Monaural Beat Stimulation on Anxiety and Cognition. Front. Hum. Neurosci. 11, (2017).
13. Weller, L. Binaural Beats Vs. Monaural Beats: What’s the Difference & Which is Better? https://www.binauralbeatsfreak.com/binaural-beats/binaural-beats-vs-monaural-beats.
14. Oster, G. Auditory Beats in the Brain. Sci. Am. 229, 94–103 (1973).
15. Greenwood, M. Can Binaural Beats Really Help You Sleep and Improve Anxiety? SELF (2022).
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