In 2015 I developed a theory that the human response to music is a mutated copy of an evolutionary pre-cursor, and the most likely pre-cursor is a response to speech-like sounds, where this response plays a role in the initial learning of language. I have documented the development of my theory in my &quot;What is Music?&quot; blog at <a href="http:&#x2F;&#x2F;whatismusic.info&#x2F;blog&#x2F;" rel="nofollow">http:&#x2F;&#x2F;whatismusic.info&#x2F;blog&#x2F;</a>.<p>In their analysis of the human auditory cortex, Norman-Haignere et al found six distinct functional groups of neurons. One of those groups is identified as a &quot;music area&quot;. Another one of the groups is a close match for the evolutionary pre-cursor that I predicted - a group of neurons that respond to speech sounds, whether or not those sounds belong to the listener&#x27;s native language.<p>The initial assumption of my theory is that the primary function of music is to temporarily alter mood. Evidence for this function comes from the strong effect that music has on some people who are &quot;addicted&quot; to daydreaming.<p>My theory suggests that the response to speech-like sounds also induces an altered mood, when an infant is learning language for the first time. This alteration in mood helps the infant to identify language as a special stimulus which is important and which needs to be processed and understood as something that follows its own peculiar and complex set of rules which are not particularly related to the rules that describe all the other aspects of reality that the infant is learning about. The altered mood may also help the infant to learn that the meaning attached to some language utterances relates to things beyond immediate reality, ie things that other people are thinking about which are not in the &quot;here and &quot;now&quot;. (This would relate to the similar effect that music has on our emotional reactions to things we are thinking about that are not in the &quot;here and now&quot;.)