Dopamine and frontostriatal networks in cognitive aging

Klostermann, Ellen C.; Braskie, Meredith N.; Landau, Susan M.; O'Neil, James P.; Jagust, William J.

doi:10.1016/j.neurobiolaging.2011.03.002

« Previous Next »Neurobiology of Aging
Volume 33, Issue 3 , Pages 623.e15-623.e24, March 2012

Dopamine and frontostriatal networks in cognitive aging

Ellen C. Klostermann
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Corresponding author at: Helen Wills Neuroscience Institute, 132 Barker Hall, MC# 3190, Berkeley, CA 94720-3190, USA. Tel.: +1 510 643 6616; fax: +1 510 643 4966
Meredith N. Braskie
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA
Susan M. Landau
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
James P. O'Neil
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
William J. Jagust
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

Received 8 September 2010; received in revised form 11 January 2011; accepted 1 March 2011. published online 22 April 2011.

Abstract

Recent studies have linked dopamine to differences in behavior and brain activity in normal individuals. We explored these relationships in older and younger adults by investigating how functional connectivity between the striatum and prefrontal cortex is related to caudate dopamine and verbal working memory task performance. We studied 12 young and 18 older participants with functional magnetic resonance imaging (fMRI) during this task, and used positron emission tomography with the tracer 6-[¹⁸F]-fluoro-L-m-tyrosine (FMT) to assess dopamine synthesis capacity. Younger adults had a greater extent of frontal caudate functional connectivity during the load-dependent delay period of the working memory task than the older participants. Across all subjects, the extent of this functional connectivity was negatively correlated with dopamine synthesis capacity, such that participants with the greatest connectivity had the lowest caudate 6-[¹⁸F]-fluoro-L-m-tyrosine (FMT) signal. Additionally, the extent of functional connectivity was positively correlated with working memory performance. Overall these data suggest interdependencies exist between frontostriatal functional connectivity, dopamine, and working memory performance and that this system is functioning suboptimally in normal aging.

Keywords: Aging , Working memory , Dopamine , Functional connectivity , FMT