Management of attentional resources in within-modal and cross-modal divided attention tasks: an fMRI study.
In the present study, we were interested in distinguishing the cortical representations of within-modal and cross-modal divided attention tasks by using functional magnetic resonance imaging. Sixteen healthy male subjects aged between 21 and 30 years underwent two within-modal (auditory/auditory, visual/visual) and one cross-modal (auditory/visual) divided attention task, as well as related selective attention control conditions. After subtraction of the corresponding control task the three divided attention tasks, irrespective of sensory modality, revealed significant activation in a predominantly right hemisphere network involving the prefrontal cortex, the inferior parietal cortex, and the claustrum. Under the cross-modal condition, however, the frontal and parietal activation was more extended and more bilateral and there also was stronger right hemisphere activation of the anterior cingulate cortex and the thalamus. In comparison to the within-modal conditions additional bilateral frontal and left inferior parietal activation was found for the cross-modal condition. The supplementary fronto-parietal, anterior cingulate cortex, and thalamus activation in the auditory/visual condition could be argued to reflect an additional demand for coordination of two ongoing cross-modal cognitive processes.
Vohn
Rene
R
Clinical Neuropsychology, Department of Neurology, RWTH Aachen University, Aachen, Germany. rene@izkf.rwth-aachen.de
Fimm
Bruno
B
Weber
Jochen
J
Schnitker
Ralph
R
Thron
Armin
A
Spijkers
Will
W
Willmes
Klaus
K
Sturm
Walter
W
D000161:Acoustic Stimulation; D000328:Adult; D001288:Attention / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D003071:Cognition / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D014796:Visual Perception / Q000502:physiology