Minor Hemisphere Major Syndromes.

Abstract

A right "minor hemisphere" does not exist as the right hemisphere is dominant for awareness (nosognosia), spatial attention, emotional regulation, facial and voice expressions, visual recognition, and topographical orientation. Without the right hemisphere, the world would be flat, deprived of general and spatial attentions, pointing preferentially to the right side of the space, lacking visual experiences and emotions, exhibiting diminished awareness of the self and environment. Clinical-related syndromes of the right hemisphere are unilateral spatial neglect, object and face visual agnosia, the anosognosia for hemiparesis and/or hemianopia, misidentification syndromes, mania, and other obsessions for the food and the body. Another key function of the right hemisphere is the modulation of the emotional processes of the linguistic communication (as prosody and facial expressions), and the tuning of some holistic aspects of language as the understanding of the abstract and figurative characters. The great mysteries of the right brain hemisphere concern the origin of the emotional nature of the human being, the way by which cognition interacts with perception and finally the human consciousness. Multidisciplinary researches in the domains of neurology, cognitive psychology, neuropsychiatry, functional neuroimaging, and neurophysiology will reveal in the future some of these mysteries.