Citation: Lee, E.; Bang, Y.; Yoon, I.-Y.;
Choi, H.-Y. Entrapment of Binaural
Auditory Beats in Subjects with
Symptoms of Insomnia. Brain Sci.
2022, 12, 339. https://doi.org/
10.3390/brainsci12030339
Academic Editor: Maria
Eulalia Rubio
Received: 14 January 2022
Accepted: 28 February 2022
Published: 2 March 2022
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Brief Report
Entrapment of Binaural Auditory Beats in Subjects with
Symptoms of Insomnia
Eunyoung Lee
1
, Youngrong Bang
2
, In-Young Yoon
3,4
and Ha-Yun Choi
1,4,
*
1
Department of Psychiatry, Veteran Health Service Medical Center, Seoul 05368, Korea; ehddbs48@naver.com
2
Department of Psychiatry, Ulsan University Hospital, Ulsan 44033, Korea; long-e@daum.net
3
Department of Neuropsychiatry, Seoul National University Bundang Hospital, Seongnam 13620, Korea;
iyoon@snu.ac.kr
4
Department of Psychiatry, Seoul National University College of Medicine, Seoul 03080, Korea
* Correspondence: chhy0402@gmail.com; Tel.: +82-2-2225-1158
Abstract:
Binaural beat (BB) stimulation, which has two different frequencies for each ear, is report-
edly effective in reducing anxiety and controlling mood. This study aimed to evaluate the brain wave
entrainment effect of binaural beats and to propose an effective and safe supplementary therapy
for relieving the symptoms of insomnia. Subjects between 20 and 59 years of age with subclinical
symptoms of insomnia were recruited from the community. Quantitative electroencephalography
was measured twice, before and two weeks after the BB intervention. Participants used the apparatus
with or without 6 Hz BB for 30 min before going to bed for two weeks. When music with BB was
played, the relative theta power increased (occipital, p = 0.009). After two weeks of intervention with
music, the theta power increased when listening to music with BB (parietal, p = 0.009). After listening
to music with BB for two weeks, the decrease in the beta power was more noticeable than after using
music-only devices when participants listened to music in the laboratory (occipital, p = 0.035). When
BB were played, the entrapment of the theta wave appeared. Therefore, exposure to music with BB is
likely to reduce the hyper-arousal state and contribute to sleep induction.
Keywords: insomnia; binaural auditory beats; QEEG; spectral analysis
1. Introduction
People with symptoms of insomnia account for 22.8% of the total population, and 5%
of people with insomnia meet the Diagnostic and Statistical Manual of Mental Disorders,
fourth edition (DSM-IV) criteria [
1
]. In a study based on the International Classification of
Diseases, Tenth Revision (ICD-10) or the hypnotic prescription using the National Health
Insurance Service—National Sample Cohort (NHIS-NSC) data, the prevalence of insomnia
was found to be 5.78% [2].
Insomnia has the potential to increase the mortality rate from cardiovascular disease
in relation to physiological awakening, and an objectively short duration of sleep is asso-
ciated with attention shift impairment. In addition, insomnia is a risk factor for alcohol
dependence and other mental disorders. Therefore, insomnia needs to be treated because
appropriate treatment significantly lowers the severity of comorbidities and significantly
helps to improve fatigue, anxiety, depression and the quality of life [3].
For patients with insomnia, clinic visits may be delayed as they usually take over-the-
counter drugs and herbal medicines first [
4
–
6
]. Cognitive behavioral therapy (CBT) is the
recommended initial treatment [
7
–
9
] and requires the patient’s time and effort. However,
only limited clinics perform CBT. Drug treatment is widely available, but experts do not
recommend taking benzodiazepines and z-drugs in the long term because there are no
meta-analyses on the effectiveness and safety of the long-term use of sleeping pills yet [
7
–
9
].
In particular, when the elderly take benzodiazepine, side effects such as delirium, falls
and fractures are likely to occur [
10
]. Although the causal relationship has not been clearly
Brain Sci. 2022, 12, 339. https://doi.org/10.3390/brainsci12030339 https://www.mdpi.com/journal/brainsci
