Functional organization of the prefrontal cortex in visual and auditory working memory

old_uid1486
titleFunctional organization of the prefrontal cortex in visual and auditory working memory
start_date2006/06/29
schedule11h30
onlineno
summaryThe aim of these studies was to investigate functional organization of the prefrontal cortex in verbal, spatial, and nonspatial working memory in visual and auditory modalities using functional magnetic resonance imaging (fMRI). Extensive evidence from behavioral, neuroimaging, and lesion studies have indicated that the neural systems for spatial and verbal working memory are distinct. There are, however, only a few imaging experiments that directly compare nonspatial visual and verbal working memory activation and there is no conclusive evidence for segregation of these two systems. The present results suggest that there is a hemispheric dissociation in the neural systems for verbal and nonspatial visual working memory. Previous studies of the neural system responsible for maintenance of object and location information in visual working memory have provided contradictory results concerning the degree to which nonspatial and spatial information maintenance leads to distinct patterns of activation in the prefrontal cortex. The present results suggest that there is a functional topography within the prefrontal cortex for maintenance of spatial and nonspatial information. However, this is manifested as a graded response pattern rather than an absolute division between object and location working memory tasks. It has been proposed that the auditory system is also organized into two domain-specific processing streams, similar to that seen in the visual system. However, the functional neuroanatomy of this possible auditory domain-specificity is not clear. The present results support the idea that the prefrontal cortex is organized according to the type of information being maintained also in the auditory working memory.
responsiblesBerger