Cognitive Symptoms in Schizophrenia

There are frequently many cognitive symptoms in schizophrenia (sometimes termed neurocognitive symptoms) There is a wealth of evidence that at least 70% of schizophrenia patients will be affected. This occurs at the onset of the disease, before diagnosis, and also during treatment. The cognitive symptoms in schizophrenia are important, perhaps even more so than positive symptoms, because they correlate to social outcomes, work, independent living and social relationships. Furthermore neurocognitive functioning is an predictor of response to psychiatric rehabiliattion. Studies suggest that the neurocognitive impairment is present in the premorbid and prodromal stage, but not to the same degree as at the onset of psychosis, that deficits are stable with little fall-off during lifetime, and that longterm neuroleptic medication does not appear to alter the course of the cognitive deficit.

What are these schizophrenia cognitive symptoms? This includes a vast array of domains: verbal memory, attention and processing speed, non-verbal memory, language, visuospatial abilities, learning, higher executive functions (judgement, conceptual and abstract thinking, monitoring and adjusting), social cognition and motor skills. This is a simplistic breakdown.

Currently available drug treatment has little effect on cognition and social functioning. Cognitive remediation therapy (CRT) has been in development for the past 40 years and it employs a variety of methods to improve cognitive functioning. It has had some success in treating neurocognitive deficits, functioning and symptoms. The present viewpoint is that CRT results in modest improvements on psychological testing, and also has a positive effect on functional outcomes when combined with psychiatric rehabilitation.

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