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Anthony G M Canavan

Publications and source records attributed to Anthony G M Canavan.

2 recordsLinked to original sources

Hemispheric dissociation of visual-pattern processing and visual rotation.

We aimed at investigating whether on-line and delayed visual pattern processing activated different areas in human prefrontal and parietal cortex. For this purpose we measured the regional cerebral blood flow (rCBF) during simultaneous and successive visual matrix processing in 10 right-handed subjects. Delayed matching to sample activated predominantly left hemispheric ventrolateral prefrontal cortex, Broca's area and parts of the parietal cortex. In contrast, visuospatial matrix rotation showed activation of the right dorsolateral prefrontal cortex and parietal lobe. The present results suggest a hemispheric dissociation of fronto-parietal circuits with a left dominance for visual pattern processing like storage and a right dominance for visuospatial processing.

Adult↗

Neural correlates of visuospatial imagery.

We studied changes in regional cerebral blood flow (rCBF) in 10 healthy right-handed subjects during a visuospatial imagery task. The subject's task consisted of drawing imagined lines connecting encircled numbers in ascending order and estimating the number of lines crossing. Compared with a control task in which there were no crossed lines, there were significant rCBF increases in the cingulate gyrus, the adjacent superior frontal gyrus and in the left inferior parietal cortex. The rCBF changes of the latter area correlated with task performance time. Since these activation areas are close to those in imagery of movement trajectories, we concluded that they appear to be a subsystem for processing mental visuospatial images.

Adult↗