Physiology of the Frontal Cortex

Abstract

The frontal association cortex comprises the homo-typical granular cortex of the frontal lobe, i. e., Brodmann’s areas 9–12, 45, and 46 (Fig. l). These areas are also labelled the “prefrontal” cortex in order to separate them from the agranular frontal cortex consisting of the premotor areas 6 and 8 and the motor speech area (Brodmann’s area 44) in the language-dominant hemisphere. Phylogenetically, the frontal granular and agranular cortex and their connections are already present in lower mammals but achieve prominence only in primates, exceeding other neo-cortical areas in relative growth, with the dorsolateral prevailing over the ventromedial aspect (Bianchi 1923; Feuchtwanger 1923; Luria 1969, 1973; Nauta 1971; Warren 1972).