Feedback learning linked to general function in schizophrenia
MedWire News: Feedback learning based on reward and punishment is impaired in schizophrenia patients but only among those with poor general psychosocial functioning, study results show.
Citing recent brain imaging studies on feedback learning, the researchers suggest that mesocorticolimbic dysfunction leads to anomalies in emotion, motivation, and reward regulation that in turn result in problems in real-life general functioning.
While cognitive function taps into higher-level brain processing, trial feedback is one of the most fundamental forms of learning in humans. "Several previous studies have attempted to investigate feedback-driven reinforcement learning in schizophrenia, but the results are heterogeneous and non-conclusive," Ahmed Moustafa (Rutgers University, Newark, New Jersey, USA) and colleagues comment in the journal Schizophrenia Research.
Although general functioning of patients with schizophrenia is strongly influenced by cognitive deficits, the role of feedback driven reinforcement learning is unknown.
In contrast to the multidimensional clinical evaluation of symptoms, the Global Assessment of Functioning (GAF) scale characterizes how illness influences community, family, and occupational functioning in the everyday lives of the patients.
For the current study, the researchers explored the clinical predictors of reward and punishment learning using a probabilistic classification task in 40 patients with schizophrenia and 20 mentally healthy controls.
Patients with schizophrenia performed similarly to healthy controls on the classification learning task, with patients showing a nonsignificant trend toward poorer performance on reward trials.
Patients with severe negative and general symptoms performed significantly worse showed on reward-learning tasks relative to controls.
Meanwhile, patients with poor general psychosocial functioning exhibited both significantly poorer reward and punishment performances relative to controls.
Multiple linear regression analyses indicated that general psychosocial functioning was the only significant predictor of reinforcement learning performance when education, antipsychotic dose, and positive, negative, and general symptoms were included in the analysis. Indeed the GAF score accounted for 14-17% of variance on reinforcement learning performance.
Moustafa et al comment: "Despite the paucity of experimental evidence, reward feedback following adequate social performance is traditionally used in the psychotherapy of severe mental disorders.
"Our results provide a theoretical background for these intervention studies implementing reinforcement learning principles in clinical practice."
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By Andrew Czyzewski