From a study by Brothers L, Shaw GL, and Wright EL:
It has been extremely difficult to quantify temporal aspects of higher level human brain function. We have found that mental rehearsals of musical performance of several minutes duration provide such a measure in that they can be highly reproducible, varying to less than 1%. These remarkable results pose fundamental neurophysiological problems [emphasis added]. It is necessary to understand the underlying neuronal bases for this accuracy in the spatial-temporal activity of billions of neurons over minutes without sensory input. Further, they present a powerful constraint on neuronal models of brain function. Such highly reproducible (in duration) mental rehearsals might be used in conjunction with multielectrode EEG recordings to look for reproducible spatial-temporal patterns. Further, we suggest that our results may provide an extremely useful behavioral correlate for high level performance.
Musicians, may in fact, be the key to revising the scientific theories of how the brain functions, and a better understanding of how the brain works in high-level mental rehearsal and performance may lead to understanding high-level performance in other activities. This is refreshing news for we neuroscience aficionados, who have been following the research, because, at least for some of us, the deterministic model does not accurately reflect the way our brains work. How else to explain the flash of insight and all the other odd, unexpected mental processes that happen?