Effects of passive tactile and auditory stimuli on left visual neglect
M. Hommel, B. Peres, P. Pollak, B. Memin, G. Besson, J. M. Gaio and J. Perret
Department of Clinical and Biological Neurosciences, Centre Hospitalier Regional Universitaire de Grenoble, France.
Patients with left-sided visual neglect fail to copy the left part of
drawings or the drawings on the left side of a sheet of paper. Our aim was
to study the variations in copying drawings induced by passive stimulation
in patients with left-sided visual neglect. No stimulation at all, tactile
unilateral and bilateral, binaural auditory verbal, and nonverbal stimuli
were randomly applied to 14 patients with right-hemisphere strokes. Only
nonverbal stimuli decreased the neglect. As nonverbal stimuli mainly
activate the right hemisphere, the decrease in neglect suggests
right-hemispheric hypoactivity at rest in these patients. The absence of
modification of neglect during verbal stimulation suggests a bilateral
hemispheric activation and the persistence of interhemispheric imbalance.
Our results showed that auditory pathways take part in the network involved
with neglect. Passive nonverbal auditory stimuli may be of interest in the
rehabilitation of patients with left visual neglect.
