The authors of this paper do not have any commercial associations that might pose a conflict of interest in connection with this manuscript.
The nature of abnormal language processing in euthymic bipolar I disorder: evidence for a relationship between task demand and prefrontal function
Version of Record online: 1 JUN 2007
Volume 9, Issue 4, pages 358–369, June 2007
How to Cite
Curtis, V. A., Thompson, J. M., Seal, M. L., Monks, P. J., Lloyd, A. J., Harrison, L., Brammer, M. J., Williams, S. C., Murray, R. M., Young, A. H. and Nicol Ferrier, I. (2007), The nature of abnormal language processing in euthymic bipolar I disorder: evidence for a relationship between task demand and prefrontal function. Bipolar Disorders, 9: 358–369. doi: 10.1111/j.1399-5618.2007.00422.x
- Issue online: 1 JUN 2007
- Version of Record online: 1 JUN 2007
- Received 28 September 2005, revised and accepted for publication 7 September 2006
- bipolar disorder;
- language tasks;
- neuropsychological dysfunction;
- prefrontal cortex
Objectives: Abnormal language processing is a consistent finding in bipolar disorder (BD). We used functional magnetic resonance imaging (fMRI) to investigate the core components of language processing as well as the impact of task demand in a group of bipolar subjects.
Methods: Twelve euthymic dextral male BD I participants receiving lithium monotherapy were matched with 12 controls. Groups were matched for age, years of education and estimated premorbid IQ. We employed a factorial design manipulating task demand (decision versus fluency) and task domain (phonetic versus semantic) to investigate differences in language processing between groups and across different task domains and requirements. Data were fitted to haemodynamic response models convolved to the experimental design. Group and task difference maps were generated.
Results: During the scanning session bipolar patients demonstrated significantly slower reaction times. However, groups demonstrated the same task accuracy except for one domain (phonetic decision). All participants activated regions known to be engaged by language tasks, but compared to controls the bipolar patients showed altered patterns of prefrontal activation which were related to the nature of the task, language processing, and increasing task demand.
Conclusions: We have demonstrated abnormal prefrontal activation in bipolar patients across a range of language tasks with varying task demands.