Last month's column introduced Dr. Elkhonon Goldberg's marvelous new book, The Executive Brain: Frontal Lobes and the Civilized Mind (2001). The column focused especially on his conceptualization of our brain's overall organization. Let's now focus on our cortex's frontal lobes, which are central to a functioning human brain, and to Goldberg's book.

Survival is dependent on an organism's ability to effectively recognize and respond to the dangers and opportunities it confronts. Our frontal lobes (and especially the prefrontal areas behind our forehead) give us a distinct advantage in this task because they allow us to move from the purely reactive behavior of most animals to being principally proactive -- capable of consciously anticipating and preparing for potential novel and familiar challenges.

The functions of our frontal lobes (comprising about a third of the cerebral cortex) were a long-time mystery. Recent developments suggest, however, that the prefrontal areas are our brain's equivalent of a corporate CEO. Goldberg reports that the prefrontal cortex is directly interconnected with every distinct functional unit of our brain, and so it coordinates and integrates most brain functions. And like a good computer search engine, it can quickly locate information necessary for decision-making. The importance of effective frontal lobes is further underscored by the growing awareness that many mental disorders (from attention deficits to schizophrenia) are associated principally with frontal lobe malfunctions.