Authors:

CUSACK, R., CARLYON, R.P. & ROBERTSON, I.H.

Reference:

Year of publication:

2001

CBU number:

5085

Abstract:

Patients with unilateral neglect frequently show a bias in their subjective midline, as measured by pointing, or by purely perceptual visual or auditory tasks. We consider several possible causes for previously observed shifts in auditory midline, specifically: hypokinesia; a supramodal distortion of space; hearing loss; and asymmetric performance across space. We measured the auditory midline of ten patients exhibiting unilateral neglect as assessed by standard visual tests. We also derived a measure of their auditory spatial discrimination on the two sides of space. No consistent deviation in midline was found, with five patients showing performance within the normal range, two a shift to the left, and three to the right. Discrimination performance was similar to controls and not asymmetric. The variability of this deficit contrasts with the consistency of a non-lateralised auditory deficit that was reliably found in the same patients. The results support the hypothesis that a shift in reference frame does not always accompany neglect.