[Interaction foci, informational synthesis and mental processes].

Brain organization of mental activity is based on the nervous integration, specialization of functions and combination of rigid and flexible connections. First of them are provided by structural changes in synapses, the second--by a coincidence of rhythmic characteristics and synchronization of the activity. These principles are realized in dynamic structures--interaction foci, revealed in the cortex during the process of mental activity by a method of mapping the intracortical interaction. Interaction foci are the centers of nervous connections. Each group has its appropriate frequency characteristics and is connected with the isorhythmic nervous elements at the periphery. Construction of the interaction focus provides the synthesis of the information coming from the sensory organs and the centers of motivations and that extracted from the memory. Informational synthesis is in the basis of the mental functions, having a rigid nucleus and a system of peripheral connections whose configuration can be changed, stipulating a unique character of experienced psychic feeling. Topography of interaction foci is different at different mental acts, realizing a principle of functional specialization. At perception the projection cortex is the center of integration, at thinking that are the cortical associative zones. Imaginable thinking is predominantly connected with the parieto-temporal, abstract--with the frontal cortical areas. Probably two basic functions of consciousness--integration of the "Self" including voluntary factor and communication-are also separated in space.(ABSTRACT TRUNCATED AT 250 WORDS)