Multiple representation in primate SI: A view from a window on the brain

This chapter summarizes recent findings regarding the functional organization of primary somatosensory cortex (SI) in primates when viewed through 'windows' on the brain with optical imaging methodologies. These views have confirmed previous knowledge regarding topographic organization in SI. They have also revealed the presence of functional domains for the processing of different sensory tactile modalities (pressure, flutter, and vibration domains). Surprisingly, the representation of these tactile modalities is quite distinct in organization from that of visual modalities (form, color, and depth) in visual cortex. Rather, tactile modality maps appear similar to visual orientation maps in primate visual cortex. Implications of these findings for the relationship of cortical organization to the sensory scene are discussed.