Entrainment in the biomusicological sense refers to the synchronization (e.g., foot tapping) of organisms to an external perceived rhythm such as human music and dance.
Neuroscientist Ani Patel proposes beat induction—referring to it as "beat-based rhythm processing"—as a key area in music-language research, suggesting beat induction "a fundamental aspect of music cognition that is not a byproduct of cognitive mechanisms that also serve other, more clearly adaptive, domains (e.g., auditory scene analysis or language)" (Patel, 2008).
Joseph Jordania recently suggested that the human ability to be entrained was developed by the forces of natural selection as an important part of achieving the specific altered state of consciousness, battle trance.
[2] Achieving this state, in which humans lose their individuality, do not feel fear and pain, are united in a shared collective identity, and act in the best interests of the group, was crucial for the physical survival of our ancestors against the big African predators, after hominids descended from the safer trees to the dangerous ground and became terrestrial.
[4] It has been proposed that this behavior resembles the process by which neurons create a phase-locked loop that permits recognition of consonant musical intervals.