basal (lower, orbital) parts of the frontal lobes of the brain; are closely related to the reticular formation of the brainstem, nonspecific nuclei of the thalamus and hypothalamus. They regulate the functional systems of the brain, mediating the course of voluntary forms of mental activity; exert a particularly powerful influence on the reticular formation, giving its activating influences a differentiated character in accordance with the program behavior formed in the frontal cortex; one of the links in the cortical mechanism for ensuring higher activation processes associated with speech instruction; it also participates in the regulation of metabolic processes, eating behavior, modulation of elementary drives, the formation of self-consciousness processes and the regulation of emotional states.