Correlation between different memory systems and striatal dopamine D2/D3 receptor density: a single photon emission computed tomography study.
OBJECTIVE
Although studies have indicated that the human basal ganglia have a specific role in different memory systems, the functional significance of the striatal dopamine activities for the basal ganglia remains less clear. This study assessed the relationship between measures of striatal dopamine activities and indices of different memory systems in healthy individuals.


METHODS
Single photon emission computed tomography and [123I]IBZM (iodobenzamide) were used to assess the striatal dopamine D2/D3 receptor density in 62 healthy volunteers aged between 19 and 61 years. All subjects underwent a Wechsler Memory Scale-Revised test.


RESULTS
Dopamine D2/D3 receptor densities in the striatum decline with age. Stepwise regression analysis showed that verbal delayed recall and working memory account for most of the variance in dopamine D2/D3 measurements. These relationships remain significantly after controlling for age effects.


CONCLUSIONS
Brain striatal dopamine activities are also significantly associated with various memory systems, in addition to motor functions. This may explain why patients with neuropsychiatric disorders may have both memory and motor impairments.
Chen
Po See
PS
Department of Psychiatry, Medical College and Hospital, National Cheng Kung University, Tainan, Taiwan.
Yang
Yen Kuang
YK
Lee
Yuh-Shiow
YS
Yeh
Tzung Lieh
TL
Lee
I Hui
IH
Chiu
Nan Tsing
NT
Chu
Ching Lin
CL
D000328:Adult; D000375:Aging / Q000502:physiology*; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000503:physiopathology; D008875:Middle Aged; D019957:Motor Skills Disorders / Q000503:physiopathology; D049268:Positron-Emission Tomography; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D050637:Receptors, Dopamine D3
C493593:DRD3 protein, human; D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3