Interaction between sensory and cognitive processes in visual recognition: the role of the associative areas of the cerebral cortex

Monkeys were taught to differentiate stimuli with different types of information and to perform a spatial choice. Development of Alzheimer's disease in experimental monkeys entailed a deficit of operative memory, a considerable enhancement of entropy related to correct decisions. In control monkeys, no significant changes of these characteristics occurred. In monkeys, following a bilateral removal of the sulcus principalis, the 7th field, or both, the operative memory deficit was also determined by two components. The specifics of disorders in the operative memory due to Alzheimer's disease suggest that cholinergic mechanisms determining the sensory processing differ from those involved in decision-making. The structural-functional organization of interaction between sensory and cognitive processes controlled by the motivation and attention system, is discussed.