TOP BRAIN, BOTTOM BRAIN

A debunking of the popular treatments of “the alleged great [vertical] divide between the 'analytical/logical' left and 'artistic/intuitive' right halves of the human brain.”

With the assistance of novelist and Providence Journal staff writer Miller (Summer Place, 2013, etc.), Kosslyn (Behavioral Sciences/Stanford Univ.; Clear and to the Point: 8 Psychological Principles for Compelling PowerPoint Presentations, 2008, etc.) focuses on how the cerebral cortex is organized laterally to process information. The author first looks at a 1982 study, using rhesus monkeys, which revealed how their brains utilized separate areas when they perceived the sizes and locations of objects. Trained to identify objects in order to receive rewards, their abilities were impaired differently when different areas of their brains were surgically removed. The removal of a lower section prevented them from recognizing shapes. When a top portion was taken out, they could no longer recognize positions. Kosslyn wondered about whether this top-bottom difference in the perceptual apparatus also occurred in humans. Subsequent studies by him and his colleagues showed that brain damage to stroke victims affected their perceptual abilities in a similar fashion. With the development of neuroimaging, researchers discovered that a similar top-bottom division in brain activation occurs in areas of the cortex that are involved when normal subjects visualize solutions to cognitive problems. Kosslyn takes this a step further with a schematic characterization that correlates four different cognitive modes based on “the degree to which a person relies on the top- and bottom-brain systems” when planning or solving problems and modes of social interaction. He gives the example of successful CEOs (exemplified by Michael Bloomberg) who typically show both top and bottom brain activation and are “most comfortable in positions that allow them to plan, act, and see the consequences of their actions,” compared to more impulsive individuals such as Sarah Palin, to whom he ascribes high top-brain but low bottom-brain activity. These people generate creative ideas but are poor at anticipating consequences.

Suggestive but not entirely convincing. A modest addition to the popular psychology/self-help shelf.