The intention to act improves unilateral left neglect: two demonstrations

The effects of abrupt onset of 2-D and 3-D distractors on prehension movements

“…The differences found for pointing and grasping in the present experiment seem to confirm previous observations of visual neglect studies, suggesting a differential visual coding according to the type of motor action performed by subjects (Edwards & Humphreys, 1999;Robertson et al, 1995Robertson et al, , 1997. It was found that picking up a metal rod produces less neglect in the form of a smaller deviation to the person's right side than when pointing to the perceived center of the same rod.…”

“…For example, differences have been found between pointing and grasping in neglect patients (Robertson et al, 1995; see also Robertson et al, 1997). In these studies, patients were required either to point to or grasp a rod positioned to the right, centrally, or to the left.…”

“…A strong rightward bias in their performance was evident only with the pointing action. Robertson et al (1995Robertson et al ( , 1997 suggested that the frame of reference used to represent visual information is different for pointing and grasping. Furthermore, they suggest that, given the preplanning differences for pointing and grasping (see Carnahan et al, 1993), the attentional demands for grasping may be different than those for pointing (Robertson et al, 1995(Robertson et al, , 1997.…”

“…To investigate the issue of task demands, pointing and grasping movements will be compared. Recent evidence suggests that visuomotor control can be different for pointing and grasping movements showing differences at the preprogramming and kinematic levels (Carnahan, Goodale, & Marteniuk, 1993;Robertson, Nico, & Hood, 1995, with grasping requiring a greater on-line computation than pointing. In particular, subjects were required to grasp (Experiment 1) and point (Experiment 2) to a target in the presence of a 3-D object or a 2-D photographic image distractor.…”

Neurologic Music Therapy in Cognitive Rehabilitation

“…The researchers suggested that the arousal effects of music-specifically on the right brain hemisphere, which is lesioned in visual neglect states-may underlie this positive outcome. In this context Robertson Mattingley, Rorden, and Driver (1998) have shown that unilateral neglect can be dramatically altered by changing the functioning of the brain's arousal system, and have used these findings to develop other arousal-based neglect training techniques, including auditory-based techniques (Robertson, Nico, & Hood, 1995). Frassinetti and colleagues (Frassinetti, Bolognini, & Ladavos, 2002;Frassinetti, Pavani, & Ladavos, 2002) have provided remarkable evidence that auditory stimuli can enhance visual perception in neglect states.…”