Task dependent processing of visual information about target acceleration

The objective of this study was to investigate the sensitivity of the perce ptual and motor systems to target acceleration information using verbal mag nitude estimations of turf ct acceleration and manual interception of these targets. The result:, showed that in the pereptual task the participants w ere responding mainly to acceleration threshold values, which is accelerati on as a function of initial, final, and average velocities, rather then to the absolute accelerations. When manually intercepting the targets the part icipants responded mainly to the absolute acceleration value and target ini tial velocity. Thus, these results suggest that target motion can be proces sed in the ventral (perception) and dorsal (action) visual streams however different motion characteristics are processed in these streams depending o n the required output. (C) 2000 Academic Press.