Signals from the ear hit the brain in the temporal lobe, specifically in the primary auditory cortex of the left temporal lobe. Here, we process the signals of speech and store our vocabularies. And to some extent, the right temporal lobe controls how we use this speech. And so damage to the left temporal lobe can affect the ability to interpret and create speech, while damage to the right temporal lobe can remove the governor that decides how much speech is appropriate (see San Francisco mayor Gavin Newsom’s 2008 seven-plus-hour state of the city address).
The right temporal lobe also stores our list of faces, and so damage can result in prosopagnosia, or face blindness, as this list becomes detached from the faces it represents. Perhaps because a damaged temporal lobe struggles to interpret sound information, many people with temporal lobe damage experience cross-modal sensory experiences, including “hearing colors.”