THE MISSING LINK - THE ROLE OF INTERHEMISPHERIC INTERACTION IN ATTENTIONAL PROCESSING

Although interhemispheric interaction via the callosum is most often c onceived as a mechanism for transferring sensory information and coord inating processing between the hemispheres, it will be argued here tha t the callosum also plays an important role in attentional processing. Experiments will be presented that support this viewpoint, both when attention is conceptualized as a resource and when it is conceptualize d as a selective mechanism for gating sensory information. Interhemisp heric interaction is posited to aid attentional processing because it allows for a division of labor across the hemispheres, and allows for parallel processing so that operations performed in one hemisphere can be insulated from those executed in the other. Given this additional role for interhemispheric processing, it is suggested that the corpus callosum should be considered a component in the network of neural str uctures that underlie attentional control. (C) 1998 Academic Press.