Functional Cortical Levels Within Units 2 and 3

Abstract

Luria further divides functional units 2 and 3 based on the level of reception, analysis, and comprehension (functional unit 2) and the level of organization and preparation of the motor response (functional unit 3) resulting from higher-order anatomical processors and the spread of information across surrounding cortical zones. More specifically, sensory information from our eyes and ears and from each of the other sensory modalities arrives at its own primary projection cortex in the part of the brain specialized for the processing of that type of sensory information. Vision projects onto the calcarine or striate cortex located at the medial occipital lobe. Audition projects onto Heschl’s gyrus at the anterior superior temporal lobe represented by Brodmann’s area 41. Somatic senses including touch, pressure, cold, warm, pain, and itch project onto the anterior parietal lobe at the somatosensory cortex represented by Brodmann’s areas 3, 1, 2. The German anatomist Korbinian Brodmann published his anatomical maps of human and nonhuman primates based on the cytoarchitectural features of the neurons he observed in the cerebral cortex using the Nissl stain. These maps are potentially very useful for communication purposes and for readily locating a cortical region.