In his 1997 book How the Mind Works, Canadian linguist and cognitive scientist Steven Pinker famously described music as 'auditory cheesecake', a nice enough thing but not one that is necessary to the functioning of human life or society.

Music is "an exquisite confection crafted to tickle the sensitive spots of at least six of our mental faculties," he wrote, but it is merely a fortunate byproduct of the development of the modern mind rather than the evolutionary great leap forward that language was.

Others, including the British archaelogist Steven Mithen in The Singing Neanderthal, argue differently, believing our ancestors had a proto-language, a single evolutionary precursor to both language and music, and that we have retained both strands as separate and yet overlapping methods of communication.

Professor Alan Harvey, chair of the University of Western Australia's neuroscience discipline, invited speaker at the Australian Neuroscience Society annual meeting in Hobart this week and keen musician, is more inclined to follow the latter camp.

Harvey has been threatening to write a book about his theories of music and the evolution of the modern mind for a decade, and he might just go through with it. He has recently written an article for Music Forum, the journal of the Music Council of Australia, encapsulating his thoughts, and is keen to assist in efforts to bring music into the mainstream of cognitive neuroscience by bringing together the science and the evolutionary story into one narrative.

"This is something that people have thought about for three or four thousand years - what music is, why we respond to it, how it has its impact on us, why it is universal," Harvey says.

"Why is it that every group or tribe or nation has music as part of ceremonies and rituals? I actually think that it has profound roles in human communication, especially group communication. What I'll talk about [at the ANS meeting] is how music is processed in the brain, how it relates to language processing, how old we are and when did we evolve language and music, and discuss possible reasons why we retained these two strands of communication."

Researchers in the field such as Mithen believe there is what is called a musi-language, or proto-language, that is mimetic rather than linguistic. Harvey points to the intriguing links between manual gestures and language, for example the role of Broca's area in both speech and complex hand movements.

"We tend to think of Broca's as a motor speech area but it's much more than that," he says. "Then the question is, how recently did we acquire language? And if we acquired language, why did we retain music, which has some overlap in its brain processing but also has some distinct circuitries as well - that's why you get things like amusia. This is what Oliver Sachs writes about - you can lose the ability to process music but not language and vice versa.

"The controversial element in all this is that it may be that without music, the wonder of language and the evolution of consciousness that goes with it was difficult to handle without some compensatory cognitive system that broke down the barriers between individuals. We know that it's involved in group activities, that between mother and infant language is essentially musical, we know that it's involved in all sorts of collective thinking and expression.

"I think the reason it has been preserved is that it's an essential part of our modern cognitive make-up. Some of the areas that are activated in the brain that are involved in things like altruistic acts and reward acts, we can now map. Some of the areas that are activated overlap with areas that are activated when you listen to music you like. They are also activated when you look at erotica. This isn't coincidental at all, in my opinion."