Poor hand-pointing to sounds in right brain-damaged patients: not just a problem of spatial-hearing.
We asked 22 right brain-damaged (RBD) patients and 11 elderly healthy controls to perform hand-pointing movements to free-field unseen sounds, while modulating two non-auditory variables: the initial position of the responding hand (left, centre or right) and the presence or absence of task-irrelevant ambient vision. RBD patients suffering from visual neglect, unlike RBD patients without neglect and healthy controls, showed a systematic rightward error in sound localisation, which was modulated by the non-auditory variables. Localisation errors were exacerbated by initial hand-position to the right of the body-midline, and reduced by the leftwards initial hand-position. Moreover, for the visual neglect patients, mere presence of ambient vision worsened localisation errors. These results demonstrate that although hand-pointing to sounds has often been considered a straightforward approach to investigate sound-localisation abilities in brain-damaged patients, in some patients it may actually reveal localisation deficits that reflect a combination of impaired spatial-hearing and spatial biases from other sensory modalities (i.e., vision and proprioception).
Pavani
Francesco
F
Dipartimento di Scienze della Cognizione e della Formazione, Università degli Studi di Trento, Rovereto, Italy. francesco.pavani@unitn.it
Farné
Alessandro
A
Làdavas
Elisabetta
E
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001308:Auditory Perceptual Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D001925:Brain Damage, Chronic / Q000209:etiology / Q000503:physiopathology; D002545:Brain Ischemia / Q000150:complications / Q000503:physiopathology; D004292:Dominance, Cerebral / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology*; D009068:Movement / Q000502:physiology; D010468:Perceptual Disorders / Q000209:etiology / Q000503:physiopathology; D012016:Reference Values; D013017:Sound Localization / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology