Pointing with left vs right hand in left visual field neglect

The authors report the detection performances of three subjects with unilateral left visual neglect as they were submitted to a closed-loop manual pointing task in the reaching field. Results show, for all three subjects, better detection performances when manual pointing was executed with the left hand—i.e. contralateral to the lesion—than when made with the right hand. Given that, for both hands, signal detection conditions were the same, these results are discussed according to: (a) other studies having showed changes in the expression of neglect as induced by changes in the nature or the strategy of the task; (b) the concept of an indissociable sensorimotor central processing; and (c) one of the models put forward to account for unilateral spatial neglect which includes a motor representation.