Mind machine

A mind machine (aka brain machine or light and sound machine) uses pulsing rhythmic sound, flashing light, or a combination of these. Mind machines can induce deep states of relaxation^[1] or concentration.^[2]

The process applied by some of these machines is said to induce brainwave synchronisation or entrainment.^[3]

^ McConnell, Patrick A; Froeliger, Brett; Garland, Eric L; Ives, Jeffrey C; Sforzo, Gary A (2014). "Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal". Frontiers in Psychology. 5: 1248. doi:10.3389/fpsyg.2014.01248. PMC 4231835. PMID 25452734. binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.
^ Colzato, Lorenza S; Barone, Hayley; Sellaro, Roberta; Hommel, Bernhard (2015). "More attentional focusing through binaural beats: evidence from the global-local task". Psychological Research. November 26 (1): 271–277. doi:10.1007/s00426-015-0727-0. PMC 5233742. PMID 26612201. While the size of the congruency effect (indicating the failure to suppress task-irrelevant information) was unaffected by the binaural beats, the global-precedence effect (reflecting attentional focusing) was considerably smaller after gamma-frequency binaural beats than after the control condition. Our findings suggest that high-frequency binaural beats bias the individual attentional processing style towards a reduced spotlight of attention.
^ Wackermann, J.; Putz, P.; Allefeld, C. (2008). "Ganzfeld-induced hallucinatory experience, its phenomenology and cerebral electrophysiology" (PDF). Cortex. 44 (10): 1364–1378. doi:10.1016/j.cortex.2007.05.003. PMID 18621366. S2CID 18683890.

[binaural_relaxation-1] McConnell, Patrick A; Froeliger, Brett; Garland, Eric L; Ives, Jeffrey C; Sforzo, Gary A (2014). "Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal". Frontiers in Psychology. 5: 1248. doi:10.3389/fpsyg.2014.01248. PMC 4231835. PMID 25452734. binaural-beat associated HRV significantly predicted subsequent reported relaxation. Findings suggest that listening to binaural beats may exert an acute influence on both LF and HF components of HRV and may increase subjective feelings of relaxation.

[binaural_attention-2] Colzato, Lorenza S; Barone, Hayley; Sellaro, Roberta; Hommel, Bernhard (2015). "More attentional focusing through binaural beats: evidence from the global-local task". Psychological Research. November 26 (1): 271–277. doi:10.1007/s00426-015-0727-0. PMC 5233742. PMID 26612201. While the size of the congruency effect (indicating the failure to suppress task-irrelevant information) was unaffected by the binaural beats, the global-precedence effect (reflecting attentional focusing) was considerably smaller after gamma-frequency binaural beats than after the control condition. Our findings suggest that high-frequency binaural beats bias the individual attentional processing style towards a reduced spotlight of attention.

[Wackermann-3] Wackermann, J.; Putz, P.; Allefeld, C. (2008). "Ganzfeld-induced hallucinatory experience, its phenomenology and cerebral electrophysiology" (PDF). Cortex. 44 (10): 1364–1378. doi:10.1016/j.cortex.2007.05.003. PMID 18621366. S2CID 18683890.

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