What is learning?
Learning is the ability to acquire, or change, existing knowledge, behaviours or skills. There are two distinct forms of learning: explicit (or declarative) learning occurs during a high level of consciousness regarding specific learnt content, for example, memorising information for an exam. Implicit (or procedural) learning is less conscious and refers to learning which is gained from task performance, for example, juggling. Explicit verbal learning can be measured with the Hopkins Verbal Learning test, the California Verbal Learning test and verbal list-learning. The Brief Visuospatial memory test, the Rey design learning test, the Rey complex figure test, and visual reproduction all measure explicit visual learning. Implicit learning can be measured using the Serial Reaction Time task where learning is inferred from reduced reaction time to stimuli.
What is the evidence for learning?
Compared to people without schizophrenia, moderate to high quality evidence finds medium to large effects of poorer verbal learning, verbal memory, verbal paired associate learning, verbal recognition, and Serial Reaction Time performance in people with schizophrenia. There were small to medium-sized associations between more severe negative and disorganised symptoms and poorer visual and verbal learning.
Moderate quality evidence finds small to medium-sized effects of poorer visual learning, with no differences in verbal learning, in people at clinical high risk for psychosis who transitioned to psychosis compared to people at clinical high risk for psychosis who did not transition to psychosis.
Compared to people with affective psychosis (e.g. bipolar disorder), there was a small effect of poorer performance in people with schizophrenia on the California Verbal Learning Test total free recall subscale, with no differences on the long delayed free recall or recognition hits subscales.
Overall, moderate to high quality evidence finds greater improvements in explicit learning, but not implicit learning, with second-generation antipsychotics than with first-generation antipsychotics. Specifically, treatment with second-generation olanzapine, clozapine and risperidone, and first-generation haloperidol, result in improvements in explicit learning.
Moderate to high quality evidence showed small associations between better verbal learning and better community functioning, social behavior, problem-solving and social skills. Moderate to low quality evidence finds better verbal learning is also associated with better work capacity.
Moderate to high quality evidence finds a small effect of better verbal learning and memory in people with a psychotic disorder and a substance use disorder than in people with a psychotic disorder and no substance use disorder.
Green - Topic summary is available.
Orange - Topic summary is being compiled.
Red - Topic summary has no current systematic review available.