Regular Articles

Brain Cortical Thickness and Surface Area Correlates of Neurocognitive Performance in Patients with Schizophrenia, Bipolar Disorder, and Healthy Adults

C.B. Hartberg^a1 c1, K. Sundet^a2a3, L.M. Rimol^a1, U.K. Haukvik^a1a4, E.H. Lange^a1a4, R. Nesvåg^a1a4, A.M. Dale^a3a5a6, I. Melle^a1a3, O.A. Andreassen^a1a3 and I. Agartz^a1a7

^a1 Institute of Clinical Medicine, Psychiatry Section, University of Oslo, Norway

^a2 Department of Psychology, University of Oslo, Norway

^a3 Division of Mental Health and Addiction, Psychosis Research Unit, Oslo University Hospital, Norway

^a4 Department of Psychiatry, Diakonhjemmet Hospital, Oslo, Norway

^a5 Department of Neurosciences, University of California San Diego, La Jolla, California

^a6 Department of Radiology, University of California San Diego, La Jolla, California

^a7 Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway

Abstract

Relationships between cortical brain structure and neurocognitive functioning have been reported in schizophrenia, but findings are inconclusive, and only a few studies in bipolar disorder have addressed this issue. This is the first study to directly compare relationships between cortical thickness and surface area with neurocognitive functioning in patients with schizophrenia (n = 117) and bipolar disorder (n = 121) and healthy controls (n = 192). MRI scans were obtained, and regional cortical thickness and surface area measurements were analyzed for relationships with test scores from 6 neurocognitive domains. In the combined sample, cortical thickness in the right rostral anterior cingulate was inversely related to working memory, and cortical surface area in four frontal and temporal regions were positively related to neurocognitive functioning. A positive relationship between left transverse temporal thickness and processing speed was specific to schizophrenia. A negative relationship between right temporal pole thickness and working memory was specific to bipolar disorder. In conclusion, significant cortical structure/function relationships were found in a large sample of healthy controls and patients with schizophrenia or bipolar disorder. The differences that were found between schizophrenia and bipolar may indicate differential relationship patterns in the two disorders, which may be of relevance for understanding the underlying pathophysiology. (JINS, 2011, 17, 1080–1093)

(Received February 01 2011)

(Revised July 08 2011)

(Accepted July 08 2011)

Keywords

• MRI;
• Neuropsychological tests;
• Cerebral cortex;
• Brain structure;
• Cognition;
• Brain mapping

Correspondence:

^c1 Correspondence and reprint requests to: Cecilie Bhandari Hartberg, P.O. Box 85, Vinderen, University of Oslo, N-0319 Oslo, Norway. E-mail: c.b.hartberg@medisin.uio.no