Binaural sound stimulation at pink noise frequencies to reduce sleep consolidation time and its effects on bispectral index (BIS)

Binaural sound is a type of sound that allows you to experience a spatial and three-dimensional auditory sensation and, in recent research, has been used as an alternative to drugs to induce a state of relaxation, including sleep itself in several experiments with promising results and with no adverse effects. Pink noise, on the other hand, is a special class of white noise in which the power per unit bandwidth is higher in the audio spectrum. Typically generated in the audible spectrum between 20Hz and 20kHz, rain, the sound of a fan, a waterfall, or the sound experienced in a moving car all have pink noise frequencies, so it becomes clear why some people go into a state of relaxation or sleep when listening to these sounds. This work presents the design of an auditory stimulation system that combines binaural technology and sound at pink noise frequencies to induce a state of sleep and its effects on the bispectral index (BIS) that is used to determine the level of sedation in patients at the time of undergoing a surgical procedure and that allows, in the same way, to know the level of sleep in which the person is. For this research, an algorithm was developed that combines binaural sound and pink noise and the experiment was carried out on 12 volunteer nurses with night shifts who were subjected to different auditory stimulations (without sound, with pink noise, with binaural sound, and with binaural sound at pink noise frequencies) finding that the combination has greater relaxing effects than each stimulus separately, this under controlled conditions and with volunteers without disturbing any sleep.