Multisensory localization of sounds: behavioral and neuropsychological evidences.
Multiple Paper Presentation

Nadia Bolognini
Department of Psychology University of Bologna

     Abstract ID Number: 14

Abstract
Multisensory neurons play a specific role in superior colliculus (SC) mediated behaviours because they form the mayor component of the output circuitry of the SC. Thus, those spatial stimulus configurations that enhance stimulus salience in SC would increase also orientation behaviours. In the first experiment, data from normal subjects show that a spatially coincident visual cue can improve the accuracy to localize degraded auditory targets, hard to localize when presented alone. In contrast, no improvement was found when the two stimuli were presented in separate loci. The spatial specificity of these crossmodal effects closely parallels the neurophysiological data, suggesting the involvement of multisensory neurons in bimodal localization. In the second experiment the ability of a visual stimulus to improve the localization of sounds was investigated in a patient with a selective deficit of auditory spatial localization. The results show an amelioration of patient’s localization performance after the bimodal stimulus presentation. Moreover, the magnitude of facilitation varied in a spatial specific way. This study demonstrates that a multisensory integrated system coding both visual and auditory stimuli can play a specific role in the modulation of spatial representational deficits in patients with a deficit in auditory modality.

To be Presented at the Following Symposium:
Within-modal vs. cross-modal processes: neurons, behavior and clinical studies
Other papers in this Symposium:

• Terrence Stanford
  Wake Forest Univ. Sch. of Med.
  *Benjamin Rowland
  Wake Forest Univ. Sch. of Med.
  *Barry Stein
  Wake Forest Univ. Sch. of Med.
  Modeling the Biophysical Basis of Multisensory Integration in the Superior Colliculus
• Mark Wallace
  Neurobiology & Anatomy, Wake Forest Univ Sch Med
  Developmental Plasticity in Multisensory Representations