Impaired associative inference in the early stage of psychosis.
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ABSTRACT:
SUBMITTER: Armstrong K
PROVIDER: S-EPMC6767612 | biostudies-literature | 2018 Dec
REPOSITORIES: biostudies-literature
Publications
Impaired associative inference in the early stage of psychosis.
Armstrong Kristan K Avery Suzanne S Blackford Jenni U JU Woodward Neil N Heckers Stephan S
Schizophrenia research 20180627
Relational memory is impaired in chronic schizophrenia. It is unclear if similar deficits are already present in the early stage of psychosis. We used the Associative Inference Paradigm to test relational memory ability in the early stage of a non-affective psychotic disorder. Eighty-two early stage psychosis patients and 67 healthy control subjects were trained on 3 sets of 30 paired associates: H-F1 (house paired with face), H-F2 (same house paired with new face), F3-F4 (two new faces). Subjec ...[more]
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Project description:BackgroundPrevious studies indicate that the transition to psychosis is associated with dynamic changes of hippocampal integrity. Here we explored hippocampal volume and neural activation during a relational memory task in patients who were in the early stage of a psychotic illness.MethodsForty-one early psychosis patients and 34 healthy control subjects completed a transitive inference (TI) task used previously in chronic schizophrenia patients. Participants learned to select the "winner" of two sets of stimulus pairs drawn from an overlapping sequence (A > B > C > D > E) and a nonoverlapping set (a > b, c > d, e > f, g > h). During a functional magnetic resonance imaging scan, participants were tested on the trained pairs and made inferential judgments on novel pairings that could be solved based on training (e.g., B vs. D). Hippocampal volumes were manually segmented and compared between groups. Functional magnetic resonance imaging analyses included 27 early psychosis patients and 30 control subjects who met memory training criteria.ResultsGroups did not differ on inference performance or hippocampal volume and exhibited similar activation of medial temporal regions when judging nonoverlapping pairs. However, patients who failed to meet memory training criteria had smaller hippocampal volumes. Neural activity during TI was less widespread in early psychosis patients, but between-group differences were not significant. Hippocampal activity during TI was positively correlated with inference performance only in control subjects.ConclusionsOur results provide evidence that relational memory impairment and hippocampal abnormalities, well established in chronic schizophrenia, are not fully present in early psychosis patients. This provides a rationale for early intervention, targeting the possible delay, reduction, or prevention of these deficits.
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