ABSTRACT
In this chapter we review work, from our laboratory and other groups, that has used functional neuroimaging to study the cerebral cortical basis of the human tactile perception of form. This is an area that has been the subject of considerable investigation over the past few years. Although we still do not have a complete understanding of the relevant neural processes and some of the findings remain controversial, a significant body of knowledge has been accumulated, as we hope the reader will agree after perusing this chapter. We begin by reviewing studies addressing form processing within somatosensory cortical regions. Next, we cover work demonstrating that various areas of extrastriate visual cortex are active during tactile form perception in normally sighted humans, and explore the potential role of such activity. This work is relevant to the observations, described in the chapter by Pascual-Leone et al. in this volume, that visual cortical areas are recruited for Braille reading following visual deprivation. Finally, we turn to findings indicating that premotor cortical regions are also recruited during tactile form perception even in the absence of movement, and consider the implications of these findings.
