[Abstract Title]. - Society for Neuroscience

Disclosures: E.J. Davidowitz, OLIGOMERIX, Inc., A. Employment (full or part-time);
OLIGOMERIX, Inc., E. Ownership Interest (stock, stock options, patent or other intellectual
property); S. Vasan, OLIGOMERIX, Inc., F. Consultant/Advisory Board; J.G. Moe,
OLIGOMERIX, Inc., A. Employment (full or part-time); NIH, B. Research Grant (principal
investigator, collaborator or consultant and pending grants as well as grants already received);
OLIGOMERIX, Inc., E. Ownership Interest (stock, stock options, patent or other intellectual
property).
Poster
246. Alzheimer's Imaging and Biomarkers II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 246.18/R6
Topic: C.01.o. Imaging and biomarkers
Support: NIH Grant P01 AG09466
Title: Ventral processing stream dissociation of fMRI activation during explicit and implicit
memory in AD, MCI and healthy controls
Authors: *G. T. STEBBINS 1 , M. TRIVEDI 1 , C. MURPHY 1 , R. SHAH 2 , S. W. GABRIELI 3 , J.
D. E. GABRIELI 3 ;
1 Neuroloical Sci., 2 Alzheimer's Dis. Ctr., Rush Univ. Med. Ctr., Chicago, IL; 3 Brain and
Cognitive Sci., MIT, Cambridge, MA
Abstract: Memory function is dependent to a large extent on the functioning of the ventral
processing stream. Higher order visual processing occurs in the fusiform gyrus and information
is then transferred to medial temporal lobes structures critical for memory formation.
Pathological changes have been documented in this processing stream in patients with
Alzheimer‟s disease (AD), and some evidence suggest these changes may be present in
individuals with amnestic mild cognitive impairment (MCI) who have an increased risk of
developing AD. In the present study, we examined differences in fMRI activation during
encoding and repetition priming in participants with no cognitive impairment (NCI), MCI, and
mild AD. Whole brain fMRI analyses demonstrated increased activation during encoding in all
groups in multiple regions, including occipital lobe, parietal lobe, temporal lobe, frontal lobe, the
ventral process stream (fusiform gyrus), and hippocampus/parahippocampal regions.
Examination of between groups encoding differences revealed a significant reduction in
encoding related activation in MCI and AD relative to NCI in many regions, including ventral
processing stream and hippocampus/parahippocampal locations. Regions of interest (ROI)
examination of a priori defined regions, including the hippocampal/parahippocampal region,