Auditory hypergnosia as an example of psychic tonus in the temporal lobes: multiple case analyses.

In 2006, Braun proposed a new model of hemispheric specialization of energy management by the brain, which he termed the "psychic tonus" model of hemispheric specialization. The term "psychic tonus" is deliberately general. It invites further investigation designed to incorporate various behavioral and cognitive modalities. At present, any cognitive operation or behavior likely to require energy expenditure, such as cardiovascular or metabolic, is considered to be at one extreme while any cognitive operation or behavior likely to reduce energy expenditure is considered to be at the other extreme. The model states that the left hemisphere of the brain is specialized to increase psychic tonus and the right to decrease it. The model predicts that the tonus of auditory representation ought to also manifest these hemispheric specializations in the temporal lobes. Specifically, it was predicted that pathological positive auditory tonus (auditory hallucination) ought to be associated more frequently with right temporal lobe lesions. Our analysis of a large number of previously published cases of patients with unilateral lesions supports the prediction.