Premium
P3‐219: APOE and cognitive dysfunction in Alzheimer's dementia and mild cognitive impairment
Author(s) -
Kamer Adrian,
Ellis Kathryn,
Kinsella Glynda,
Ames David,
Martins Ralph,
Rowe Christopher,
Macaulay Lance,
Szoeke Cassandra,
Masters Colin
Publication year - 2012
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2012.05.1441
Subject(s) - dementia , psychology , verbal fluency test , cognition , memory impairment , episodic memory , neuropsychology , allele , population , executive functions , apolipoprotein e , audiology , clinical psychology , disease , medicine , psychiatry , genetics , biology , environmental health , gene
tional networks in AD patients. Methods: Resting-state fMRI data of 36 AD patients and 42 healthy controls (HC) were collected. After preprocessing (slice timing, head motion correction, spatial normalization, spatial smoothing (6mm), temporal filtering (0.01w0.1 Hz) and regression of six head-motion profiles, global signal, CSF signal and white-matter signal), we obtained voxel-wise functional connectivity strength (FCS) maps for each subject. For a given voxel, FCS was computed by averaging the Pearson correlation coefficients (r>0.2) of all the voxels to the voxel. The regions showing higher FCS were considered cortical hubs. To examine between-group differences in FCS, voxel-wise linear models were performed with age and gender removed. Furthermore, linear regression analysis was used to determine the correlations between the FCS and mini-mental state examination (MMSE) scores. Multiple comparisons were corrected with Monte Carlo simulations at P<0.01 and cluster size >567 mm 3. Results: Using FCS, we identified functional network hubs in both AD patients and HC groups, predominately in the bilateral posterior cingulate gyrus (PCC), medial prefrontal gyrus (MPFC), thalamus, insula, angular gyrus and supramarginal gyrus (Fig. 1A). However, AD patients showed decreased FCS in the bilateral PCC, MPFC and right insula (P < 0.01, corrected) (Fig. 1B and Table 1). The FCS in the PCC and MPFC showed positive correlations with MMSE scores in the AD patients (Fig. 2). Conclusions: We used resting-state fMRI and graph-theory approaches to map functional brain hubs in AD patients and HC. Although both of groups showed similar hub distributions (mainly located in several defaultmode regions and insula), the patients had significant lower FCS in these regions, suggesting that the network hubs with rich connections are preferentially targeted in AD.