Distinct neural substrates for visual search amongst spatial versus temporal distractors (original) (raw)
2003, Brain research. Cognitive brain research
Whether the contribution of the superior parietal cortex (BA7) to attention-demanding tasks is strictly spatial in nature remains unresolved. We used functional magnetic resonance imaging to explore the behavioural and neuroanatomical correlates of non-spatial search for a conjunction of features within a stream of temporally-distracting stimuli. In addition, we compared these data to those from a conventional visuo-spatial search task, performed by the same subjects, in order to determine the specificity of right BA7 activation. Mode of stimulus-distribution (spatial versus temporal) and search type (target defined by a single feature or a conjunction of features) were manipulated in a 2 x 2 factorial design. Behaviourally, the temporal conjunction task was shown to index temporal selective attention. Accuracy of detecting a second target varied with the temporal proximity of two successive targets when subjects searched for a conjunction of features, but not a single feature. The ...