Audiotactile interactions in front and rear space.

The last few years have seen a growing interest in the assessment of audiotactile interactions in information processing in peripersonal space. In particular, these studies have focused on investigating peri-hand space [corrected] and, more recently, on the functional differences that have been demonstrated between the space close to front and back of the head (i.e., the peri-head space). In this review, the issue of how audiotactile interactions vary as a function of the region of space in which stimuli are presented (i.e., front vs. rear, peripersonal vs. extra-personal) will be described. We review evidence from both monkey and human studies. This evidence, providing insight into the differential attributes qualifying the frontal and the rear regions of space, sheds light on an until now neglected research topic and may help to contribute to the formulation of new rehabilitative approaches to disorders of spatial representation. A tentative explanation of the evolutionary reasons underlying these particular patterns of results, as well as suggestions for possible future developments, are also provided.