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Abstract:
Abstract: Neural activity changes in frontal cortex while
monkeys learn to associate arbitrary visual stimuli with movements.
In humans, frontal and parietal areas become activated during
application of such learned rules. Here, we address whether frontal
and parietal cortices become activated when humans learn to
associate arbitrary visual stimuli with movements. Using
event-related methods, we obtained fMRI data from young adults in
frontal and parietal areas during a control movement task and
during learning to associate each of six visual cues with one of
three finger movements. Learning evoked more activation than the
control movement task bilaterally in the anterior cingulate,
parietal-occipital sulcus region, thalamus, and prefrontal cortex.
This activation pattern occurred unilaterally in the left insula,
right intraparietal sulcus and left primary motor cortex. In
contrast to prior results neither the premotor area, the
supplementary motor area (SMA) nor the preSMA exhibited more
activation during learning. The left anterior cingulate exhibited
greater activation early than late in learning, while the left
parietal-occipital sulcus and right SMA exhibited greater
activation late than early in learning. These results suggest that
brain activation during rule formation differs from that observed
during rule application. Also, the use of an event-related approach
allows the examination of response magnitude and timing in addition
to volume of activation. Support: AG10634; NS35376
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