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Abstract:
Preliminary evidence exists implicating specific
frontostriatal circuits in the capacity to inhibit attention to
irrelevant stimuli. We hypothesized that children experiencing
perinatal damage to the basal ganglia (i.e., intraventricular
hemorrhage) would demonstrate poorer behavioral performance during
a response inhibition task, as well as abnormal patterns of
activation in these circuits. Ten children (ages 6-9) with
perinatal histories of IVH were scanned during performance on a
Go-No-Go paradigm. Data were analyzed by analysis of variance with
a contiguity threshold of 3 pixels and p<0.05. Compared to a
previous study with healthy children (Casey et al., in press),
children with IVH demonstrated a higher false alarm rate (35% vs.
27%). As in the previous study, false alarm rate was positively
correlated with activation in the anterior cingulate gyrus
(r=0.54); however, the previously observed negative correlation
between false alarm rate and orbital prefrontal activation was
absent for the IVH population (r=0.15). Given that every child
demonstrated normal activation of the orbital cortex, disruption of
the frontostriatal circuits at the level of the basal ganglia
appears sufficient to impair response inhibition.
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