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: other studies having showed changes in the expression of neglect as induced by changes in the nature or the strategy of the task; the concept of an indissociable sensorimotor central processing; and one of the models put forward to account for unilateral spatial neglect which includes a motor representation.