By the time you’ve finished reading this article you’ll probably feel as though you’ve been reading science fiction. Yet it often happens that enquiring into the nature of things we hardly notice, day in day out, reveals the oddest things imaginable. And in certain instances, music can facilitate such an enquiry.

Not just a tick

In his book The Mind’s Eye, the late British neurologist Oliver Sacks wrote “there is certainly a universal and unconscious propensity to impose a rhythm even when one hears a series of identical sounds at constant intervals… we tend to hear the sound of a digital clock, for example, as ‘tick-tock, tick-tock’, even though it is actually ‘tick-tick, tick-tick’.” I might add to this acute summary that we, the listeners, impose an emphasis on the first of every two ‘ticks’.

^{Neurologist Oliver Sacks}

Let’s try a little experiment. When only those who might understand are about, try repeating in a uniform, monotone succession the pattern ‘a-b-a-b-a-b’ without any hint of emphasis. But then again, perhaps this sequence is sure to lend an emphasis owing to the pattern’s alphabetical arrangement? OK, try just ‘a-a-a-a-a-a’. Keep it going as long...