Figure 9.

Inter- and intrahemispheric connections in monkeys possibly mediating interhemispheric interactions in area 3b. Schematic diagram of selected somatosensory cortical areas that may mediate interhemispheric interactions in area 3b. Connections indicated are based on neuroanatomical studies and reviews (Killackey et al., 1983; Krubitzer and Kaas, 1990; Kaas, 2000; Wu and Kaas, 2003). The dotted vertical line indicates the midline separating the two cerebral hemispheres. Intrahemispheric connections are shown with thick arrows and interhemispheric connections are shown with thin arrows. The interhemispheric connection between the hand representations of area 3b is sparse (Killackey et al., 1983) and is shown by a dashed line. Otherwise, the schematic is not drawn to represent the scale of areas or the density of connections. However, the schematic illustrates the known pathways through which neurons in area 3b may be influenced by the opposite hemisphere. Note that there are no known direct ipsilateral pathways for information from the hand, thus, subcortical somatosensory areas are not shown.