Electronic Posters: Neuroimaging - ismrm

15:00 4456. Levodopa Differentially Modulates Subcortical Activity in Parkinson’s Disease
During Self-Initiated Internally Timed Movements Compared to Movements Following a
Cued Period.
Jolyn NA D'Andrea 1 , Angela Haffenden 2 , Sarah Furtado 2 , Oksana Suchowersky 2,3 ,
Bradley G. Goodyear, 2,4
1 Medical Science, University of Calgary, Calgary, AB, Canada; 2 Department of Clinical Neurosciences,
University of Calgary, Calgary, Alberta, Canada; 3 Medical Genetics, University of Calgary, Calgary, Alberta,
Canada; 4 Radiology, University of Calgary, Calgary, Alberta, Canada
Parkinson’s patients have difficulty performing self-initiated movements. Levodopa can reduce this functional deficit by focusing
brain activity to areas necessary for task performance. The current study investigates how levodopa modulates brain activity in
Parkinson’s patients during the performance of internally timed motor tasks, with and without a preceding cue. Our results show that
levodopa has a differential effect on the involvement of ipsilateral basal ganglia and thalamus depending on whether internally driven
movements are self-initiated or initiated by a cue. This has practical implications for helping Parkinson’s patients cope with behavioral
deficits, and could impact future pharmacological interventions.
15:30 4457. Gender Dependent Response of Dopaminergic Administration in Parkinson’s
Disease: A FMRI Study
Mohit Saxena 1 , Senthil S. Kumaran 2 , Sumit Singh 1 , Madhuri Behari 1
1 Department of Neurology, All India Institute of Medical Sciences, New Delhi, India; 2 Department of N.M.R.,
All India Institute of Medical Sciences, New Delhi, Delhi, India
Parkinson’s Disease is a neurodegenerative disorder characterized by tremors apart from bradykinesia, rigidity and postural
imbalance. The tremors often present motor dysfunction. We carried out this FMRI study to distinguish the brain activation pattern in
the male and female Parkinson’s disease patients and the response of dopaminergic drugs in male and female patients.
Tuesday 13:30-15:30 Computer 85
13:30 4458. Prenatal Alcohol Exposure Alters Cortical Functioning in Sustained and Shifting
Attention Tasks
Xiangchuan Chen 1 , Claire D. Coles 2 , Mary E. Lynch 2 , Xiaoping Hu 1
1 Biomedical Imaging Technology Center, Emory University, Atlanta, GA, United States; 2 Department of
Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, United States
Neural basis underlying behavioral alterations induced by prenatal alcohol exposure (PAE) remains unclear. In this study, fMRI was
used to investigate the cortical functioning of individuals with PAE in sustained and shifting attention tasks. The results suggest that
the composition of the cortical attention network is not significantly changed by PAE. Instead, the neural activity of some critical
regions in this network (FEF and IPS) is significantly reduced, resulting in more involvement of other regions when PAE individuals
are performing more difficult tasks. PAE individuals with or without external features may have different functional reorganization
and compensation mechanisms.
14:00 4459. Neural Underpinning from Goal-Directed Drug Seeking to Dysfunctional Stimulus-
Response Habit: Increased Nucleus Accumbens – Caudate Connectivity in Heroin Addicts
Alexander D. Cohen 1 , Chunming Xie 2 , Wenjun Li 1 , Theodore Tianrun Zhang 1 , Zheng
Yang 3 , Shi Jiang Li 1
1 Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States; 2 Biophysics, Medical College of
Wisconsin, Milwaukee , WI, United States; 3 Beijing Institute of Basic Medical Science, Beijing, China
This abstract compares resting state functional connectivity (FC) in heroin addicts to matched-control subjects using the nucleus
accumbens (NAc) as a seed in an attempt to better understand the underlying processes of addiction. Correlation values were obtained
for each subject on a voxelwise basis in 13 addiction associated regions, and then compared via t-test between groups. Increased
positive correlation was seen in the left insula, left precuneus, left posterior cingulate cortex, and bilateral caudate body in heroin
subjects vs. controls. These results suggest increased NAc – caudate connectivity may underlie the shift from goal directed to habitual
behavior in drug addiction.
14:30 4460. Cocaine Exposure History Leads to Distinct Spatial and Temporal Response
Patterns to Acute Cocaine Challenge in Rats
Hanbing Lu 1 , Svetlana Chefer 1 , Pradeep Kurup 1 , Karine Guillem 2 , D. Bruce Vaupel 1 ,
Thomas J. Ross 1 , Yihong Yang 1 , Laura L. Peoples 2 , Elliot A. Stein 1
1 Neuroimaging Research Branch, National Institute on Drug Abuse, NIH, Baltimore, MD, United States;
2 Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA
Drug abuse remains a serious social problem. Long-lasting neuroadaptations following repeated drug exposure are thought to mediate
compulsive drug seeking and taking behavior. In the present study, rats were trained to self-administered (SA) either I.V. cocaine
(n=10) or oral sucrose (n=13) for 20 days using a long-access exposure regimen (6-h sessions), followed by 30 days of abstinence. A
third untreated group (naïve rats, n=10) served as a control. Following an acute cocaine challenge, rats with repeated cocaine exposure
history demonstrate significantly reduced response. In particular, in such regions as the prelimbic cortex, the infralimbic cortex and
the ACC, cocaine SA rats have negative fMRI response, in contrast to positive response in cocaine naïve rats. These findings reinforce
the role of prefrontal cortex in translation of motivational stimuli into adaptive motor response.