[The effectiveness of suggestive techniques to improve sleep is enhanced by combining with sound stimulus based on binaural beats]. / Effektivnost' suggestivnykh metodik dlya uluchsheniya sna povyshaetsya pri sochetanii ikh so zvukovym stimulom na osnove binaural'nykh bienii.

OBJECTIVE: To test the hypothesis of the difference between 3 means of sleep latency (SL) during falling asleep: accompanied by audio stimulus embedded with binaural beats (BB); after listening to suggestive body relaxation instructions; accompanied by audio stimulus embedded with BB after listening to suggestive body relaxation instructions (that is the combination of 1 and 2). MATERIAL AND METHODS: For the purpose of the study, a special Android application was developed and installed on the subjects' individual smartphones. The application assumed screen tapping test to control for fall-asleep process. The data of 63 subjects presented with the 3 types of sound stimuli mentioned above in a counterbalanced scheme were analyzed. RESULTS: Statistical analysis confirmed the initial hypothesis about the dependence of LS on the type of sound stimulus (p<0.05). Pairwise SL comparison showed reliable difference between stimuli (3) - 1149±113 s, and (1) - 1469±89 s (p<0.01). SL for the stimulus (2) had an intermediate value of 1269±112 s (difference from (1) at a trend level). CONCLUSION: The use of background sound embedded with BBs enhances the effect of suggestive instructions to improve sleep. But it is the suggestion as a psychotherapeutic technique that is determinant.

[Monotonous sound stimuli embedded with either binaural or monaural beats have the same effect on sleep latency: study on a large subject group]. / Vliyanie binaural'nykh i monaural'nykh bienii v strukture monotonnogo zvukovogo stimula na latentnost' sna.

OBJECTIVE: The aim of this study was to test on a large group of subjects the hypothesis that sleep latency (SL) does not depend on the nature of low-frequency beats embedded into monotonous sound stimulus supplied through the fall-asleep process. Specifically, it does not depend on whether those beats are monaural (MB) or binaural (BB). MATERIAL AND METHODS: A special application for Android OS was developed and installed on the individual smartphones of 221 subjects for the purpose of the study. Three attempts were performed with each of them using 3 different kinds of monotonous sound supplied according to counterbalanced design. Three kinds of sound were identical in pitch but differed in the beat presence and type: BB, MB or sham (sound without beats). RESULTS: Repeated measures analysis of variance (rANOVA) revealed no significant statistical effect of stimulus type on SL (p=0.21). A pairwise comparison of SL for different stimulation conditions showed the null hypothesis significance level adjusted according to multiple comparison correction to be p=1.0. Thus, in this experiment SL did not significantly depend on the monotonous sound stimulus type: MB, BB, or sham. CONCLUSION: The software application developed is useful as universal platform to assess at home conditions the impact of various external factors on fall-asleep process.

[The effect of music embedded with binaural beats on heart rate parameters during nap]. / Vliyanie muzyki s effektom binaural'nykh bienii na parametry serdechnogo ritma cheloveka v protsesse dnevnogo sna.

OBJECTIVE: To test hypothesis that music embedded with binaural beats can boost activity of parasympathetic part of autonomic nervous system (PPANS) with the development of nap. MATERIAL AND METHODS: The power of high-frequency component of heart rate variability spectrum computed on successive 2-minute intervals during 20-minute nap was a comparison criterion. The criterion was compared during nap accompanied by music with embedded binaural beats (stimulus condition) and nap in silence (control condition). RESULTS AND CONCLUSION: Statistical comparison revealed the increase of PPANS activity during nap in stimulus condition vs. control condition. It is consistent with conclusions of other papers about positive effect of sound stimuli embedded with binaural beats on PPANS.

[The effect of music containing binaural beats on daytime fall-asleep dynamics]. / Vliianie muzyki, soderzhashchei binaural'nye bieniia, na dinamiku dnevnogo zasypaniia.

AIM: To test the hypothesis that listening to the music with the effect of binaural beats of theta and delta range during nap decreases sleep latency defined by 2nd slow wave sleep stage appearance, as well as improves its stability. MATERIAL AND METHODS: The experimental set of 20 min duration was established according to the counterbalanced scheme with 21 subjects. Each subject participated in two attempts: one attempt included sound stimulation (music) and another one was sham (silence). RESULTS AND CONCLUSION: The decrease in sleep latency during stimulation is not confirmed reliably. The increase in sleep stability has been confirmed reliably using nonlinear regression model. The findings can be used in the development of non-pharmacologic ways of sleep treatment.