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Abstract:
Abstract: Neuroimaging studies of false recognition have
increased in recent years. In the present fMRI study, we used the
typical false recognition paradigm to test a hypothesis that true
recognition consists of two sequential processes: event-category
judgement and retrieving past similar events. Eleven normal
subjects were participated in this study. They were instructed to
learn 18 sets of 14 semantic associates in preparation for a later
memory test. In the test phase (fMRI), subjects were asked to
recognize for words projected on a screen. All of the words were
presented in pairs from each set, and those words consisted of the
following conditions: True--True words (TT), True word--Related
lure(TR), Related--Related lures (RR), and Unrelated--Unrelated
lures(UU). Significant BOLD contrasts were detected in parietal
lobes and ventrolateral and dorsolateral resions of prefrontal
cortex. The left ventrolateral cortex were activated in RR and UU,
but not in TT and TR. This suggests that the left ventrolateral
prefrontal cortex correlates with event-category judgement and
retrieving past similar events, because judgement for pairs
including true word(s) may be based on the perceptual familiarity,
whereas that for pairs including no true word may be largely based
on the comparison with the same-category word that they were sure
to be true.
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