Evidence for neuropsychological deficits in schizophrenia is substantial whereas evidence for the specificity of dysfunction is relatively sparse. To assess specificity, we compared neuropsychological function in patients with chronic schizophrenia, patients with chronic psychotic bipolar disorder and normal controls. Groups were comparable on age, ethnicity and expected intellectual ability (based on single word reading). Patients with schizophrenia and bipolar psychoses were also relatively similar on age at onset and number of hospitalizations. Using multivariate analyses of variance with sex and parental SES as covariates (our primary analyses), patients with schizophrenia were significantly more impaired than controls on seven of eight neuropsychological functions (all but verbal ability), and were significantly more impaired than bipolar patients on abstraction, perceptual-motor speed and vigilance. Bipolar patients were significantly impaired compared to controls on declarative verbal memory, and showed moderate-to-large effect size decrements on abstraction, perceptual-motor speed and vigilance. Results were not attenuated when IQ was controlled, which was significantly lower in patients with schizophrenia. Analyses indicated that the two psychiatric groups had similar profile patterns, but that patients with schizophrenia had a more severe impairment than patients with bipolar psychoses. Further research is required to determine whether similar mechanisms underly the neurocognitive deficits in these disorders.
|Number of pages||14|
|State||Published - 1 Jan 2002|
Bibliographical noteFunding Information:
We thank Gwen Barnes, Mimi Braude, Deborah Catt, Joanne Donatelli, Tova Ferro, Lisa Gabel, David Goldfinger, Robin Green, Lynda Jacobs, Jennifer Koch, Denise Leville, Cathy Monaco, Anne Shore, Jason Tourville, Rob Trachtenberg, Judith Wides, and Drs Keith Hawkins, Theresa Pai, John Pepple, and Rosemary Toomey for their contributions to the projects. We also thank Drs Anna Mitchell, David Osser, and Larry Albert of the Taunton State Hospital for assistance in recruiting participants. Preparation of this article was supported in part by National Institute of Mental Health (NIMH) Grants MH43518 (MERIT Award), and MH46318 to Dr Tsuang, the Veteran's Affairs Medical Research and Health Services Research and Development Programs, an NIMH Scientist Development Award (K21 MH00976) and NARSAD Young Investigator Award to Dr Goldstein, and a NARSAD Foundation Grant and Stanley Foundation Grants to Dr Seidman.
- Bipolar disorder
ASJC Scopus subject areas
- Psychiatry and Mental health
- Biological Psychiatry