Brain development: Lightning is always seen, thunder always heard

Over a century ago, the psychologist William James proposed a thought experiment, and suggested the answer: if the eyes were forced to connect to the auditory centres of the brain, and the ears with the visual centres, we would “hear the lightning and see the thunder” [1]. James’ point was that the perceptual qualities of our sensations — what philosophers term qualia — have their origin in the brain’s central neural mechanisms, rather than in the particular physical properties of sound and light, or in the sensory receptors of the eye and ear. While this seems reasonable, a critical question remains: are the types of sensory processing that ultimately give rise to qualia innately determined properties of different cortical areas, or are they the secondary outcome of a general purpose learning algorithm applied to sensory inputs which have a different information content? If the former is the case, James’ conjecture would hold, if the latter, it need not, once learning had taken place.