RT Journal Article
SR Electronic
T1 Imaging reward function in healthy volunteers with PET and fMRI
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 309
OP 309
VO 50
IS supplement 2
A1 Nina Urban
A1 Yongxia Zhou
A1 Xiaoyan Xu
A1 Rawad Ayoub
A1 Mark Slifstein
A1 Godfrey Pearlson
A1 John Krystal
A1 Anissa Abi-Dargham
YR 2009
UL http://jnm.snmjournals.org/content/50/supplement_2/309.abstract
AB 309 Objectives In animal models, mesolimbic dopamine (DA) release has been associated with reward salience. We tested DA release using [11C]raclopride PET, and neural activity with fMRI, in 12 healthy volunteers undergoing the monetary incentive delay task (MIDT). Methods Scans were acquired for 40 min, starting 40 min after Bolus / Constant infusion of [11C]raclopride on the HR+camera, at baseline and after MIDT. BPND was derived by equilibrium analysis in the ventral striatum (VST), the cerebellum was used as reference, and ▵BPND across conditions was measured. Subjects also underwent fMRI with MIDT (2 x12 min) and BOLD signal changes were measured in both sessions. Results MIDT caused an average ▵BPND of 3.9% in VST (p=0.28). The fMRI pattern of activation was highest in the VST. Correlation of VST ▵BPND with fMRI BOLD % change during the 1st session between the highest reward condition (win$5) and neutral conditions (win/lose $0), or between win$5 and average of all conditions, yielded a trend level (r=-0.433, p=0.16) or a significant (r=-0.697, p=0.01) finding, respectively. Conclusions We did not find a significant effect of MIDT on DA release in VST. This may be related to the combination of rewarding and non-rewarding stimuli within the task, or to our delayed scanning session not detecting transient changes in DA release. However, the significant correlation in VST between ▵BPND and fMRI BOLD signal is consistent with the notion that reward related activity in the limbic striatum is related to DA transmission.