Deficits in social cognition and neurocognition are believed to underlie
schizophrenia disability. Attempts at rehabilitation have had circumscribed
effects on cognition, without concurrent improvement in broad aspects of behavior
To determine the differential effects of cognitive enhancement therapy
(a recovery-phase intervention) on cognition and behavior compared with state-of-the-art
enriched supportive therapy.
A 2-year, randomized controlled trial with neuropsychological and behavioral
assessments completed at baseline and at 12 and 24 months.
An outpatient research clinic housed in a medical center's comprehensive
care service for patients with severe mental illness.
A total of 121 symptomatically stable, non–substance-abusing but
cognitively disabled and chronically ill patients with schizophrenia or schizoaffective
Cognitive enhancement therapy is a multidimensional, developmental approach
that integrates computer-assisted training in neurocognition with social cognitive
group exercises. Enriched supportive therapy fosters illness management through
applied coping strategies and education.
Main Outcome Measures
Six highly reliable summary measures—Processing Speed, Neurocognition,
Cognitive Style, Social Cognition, Social Adjustment and Symptoms—were
tested using analysis of covariance and linear trend analysis.
At 12 months, robust cognitive enhancement therapy effects were observed
on the Neurocognition and Processing Speed composites (P<.003), with marginal effects observed on the behavioral composites.
By 24 months, differential cognitive enhancement therapy effects were again
observed for the 2 neuropsychological composites and for Cognitive Style (P=.001), Social Cognition (P=.001),
and Social Adjustment (P=.01). As expected, no differences
were observed on the residual Symptoms composite. Effects were unrelated to
the type of antipsychotic medication received. Enriched supportive therapy
also demonstrated statistically significant within-group effect sizes, suggesting
that supportive psychotherapy can also have positive, although more modest,
effects on cognitive deficits.
Many cognitive deficits and related behaviors of patients with stable
schizophrenia are improved when sufficient exposure to relevant rehabilitation