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Abstract:
Psychological theory has implicated spatial location as a key
dimension on which attentional control systems influence sensory
processes; however attention can also be focused on nonspatial
attributes such as color or form. Significant controversy remains
concerning the precise relationship between spatial and nonspatial
attentional mechanisms. Here we used event-related functional
magnetic resonance imaging during a cued attention task to identify
and contrast the neural control systems involved in spatial versus
nonspatial voluntary selective attention. A fronto-parietal network
of brain areas became activated in response to attention-directing
cues for spatial and nonspatial attention, but some of these brain
structures were differentially active to the two types of cues,
with more dorsal parietal regions supporting spatial orienting and
more inferior parietal and ventral cortical areas supporting
nonspatial orienting. These data provide physiological support for
the idea that the top-down control of attentional orienting to
different stimulus dimensions involves partially specialized
cognitive brain mechanisms.
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