Conference | Research

CORTEX conference by Laure Pisella

On The March 26, 2015

Amphi ISC
67, bd Pinel
69500 Bron

Attention and visuo-spatial working memory in the parietal cortex - a new view of the components of Balint-Holmes syndrome

Patients with bilateral posterior cortical atrophy (PCA) show reduced deployment of attention over space (Simultanagnosia) resulting in increased visual search times and under-estimations of the number of briefly presented dots. Only few of these patients, the most severe, also show ocular revisiting behaviour causing frequent omissions in visual search and over-estimations of the number of dots presented for unlimited duration. The impairment to deploy attention is considered here as bilateral covert attention deficit. Disorganised ocular exploration appears independent and is hypothesized to result from processes maintaining a salience map over time /(spatial working memory) /and especially /across saccades/.Data from optic ataxia and constructional apraxia patients respectively tend to confirm that the parietal region included in the dorsal attentional network (superior parietal lobule and intraparietal sulcus) is involved in attentional selection and localization for perception and action, and that the parietal region included in the ventral attentional network (right inferior parietal lobule) is involved in spatial working memory and visual synthesis across saccades. This is also confirmed by TMS studies.