connectivity associated with poorer cognitive function). Interestingly, in- creased middle frontal and inferior fronto-opercular SN connectivity was as- sociated with poorer processing speed, fluid reasoning and working memory. Conclusions: High Ab in healthy adults is associated with de- creased connectivity in DMN and enhanced connectivity in SN. There was a direct relationship between Ab-induced DMN connectivity decreases and cognitive performance, but an inverse relationship for Ab-induced SN connectivity increases. IC-O1-05 STRUCTURAL DIFFERENCES IN COGNITIVELY NORMAL ELDERLY INDIVIDUALS WITH ABNORMAL AMYLOID BIOMARKERS: DETECTION USING VOLUMETRIC MRI IN ADNI AND AIBL Katherine R. Gray 1 , Robin Wolz 1 , Rolf A. Heckemann 2 , Daniel Rueckert 1 , Alexander Hammers 2 , 1 Imperial College London, London, United Kingdom; 2 Fondation Neurodis, Lyon, France. Background: The ability to identify individuals in the pre-symptomatic stages of Alzheimer’s disease is desirable for early diagnosis, interven- tion and counselling, as well as drug discovery. Pathological changes in the brain precede cognitive symptoms by several years, and disease- specific biomarkers could potentially detect pre-clinical disease. So far, most efforts at early detection have focused on individuals already suffer- ing from mild cognitive impairment, or have required serial imaging over 12 months. Here, we use volumetric MRI to identify early signs of neu- rodegeneration in baseline images of cognitively normal elderly individ- uals with evidence of cortical b-amyloid deposition. Methods: Imaging and biological data are from 109 controls from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and 117 controls from the Australian Im- aging, Biomarkers & Lifestyle Flagship Study of Ageing (AIBL). Baseline MRIs from both groups were automatically segmented into 83 anatomical regions. Regional volumes were normalised by intracranial volume. Partic- ipants were assigned to risk groups based on CSF Ab1-42 in ADNI (high- risk  192pg/ml), and neocortical-to-cerebellar ratios of amyloid deposition on [11C]PiB-PET imaging in AIBL (high-risk >1.5). Normalised regional MR volumes were compared between the high- and low-risk sub-sets. Results: Among ADNI participants, 39% were classified as high-risk. Four- teen of 83 regions across the brain were significantly smaller in the high-risk group (P <0.05). Conclusions: This study shows volumetric differences— at baseline—in cognitively normal individuals differing in amyloid-based risk status for the development of Alzheimer’s disease. The consistency of regional differences observed in two independent groups suggests that volumetric MRI can reveal structural brain changes that precede the onset of clinical symptoms. It may therefore be useful in identifying early signs of neurodegeneration in healthy elderly individuals, poten- tially providing a useful early screening tool, or outcome measure for clinical trials. IC-O1-06 DISRUPTED FUNCTIONAL INTEGRITY BETWEEN TASK-POSITIVE AND TASK-NEGATIVE NETWORKSIN THE EARLY STAGES OF ALZHEIMER’S DISEASE Zhiqun Wang 1 , Mingrui Xia 2 , Qixiang Lin 2 , Yong He 2 , Kuncheng Li 1 , 1 Department of Radiology, Xuanwu Hospital of Capital Medical University, Beijing, China; 2 Beijing Normal University, Beijing, China. Background: Resting-state functional MRI (R-fMRI) has been widely used to study the pathophysiology of Alzheimer’s disease (AD). How- ever, most previous studies of AD focused on task-negative network, known as the default mode network (DMN). Here, we used R-fMRI to investigate the integrity of task-negative and -positive networks in AD patients. Methods: R-fMRI data of 17 patients with AD and 17 normal controls were collected on a Siemens Trio 3.0 Tesla MRI scanner. Data preprocessing were performed using the SPM (www.fil.ion.ucl.ac. uk/spm) and DPARSF (www.restfmri.net/forum/DPARSF) toolkits. Two 6 mm radius sphere seeds were defined separately in medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC), and the resting state functional connectivity (RSFC) between each seed and every other voxel of the whole brain were calculated for each subject. Voxel-wise two-sam- ple t-test was used to determine the significance of RSFC differences be- tween two groups at a corrected P<0.05. Results: MPFC: Several DMN (task-negative) regions including the left PCC, right inferior parietal lobe (IPL), right inferior temporal gyrus (ITG) showed decreased positive RSFC to MPFC. Several task-positive regions such as the left fusiform, bi- lateral dorsal lateral prefrontal cortex (DLPFC), inferior frontal gyrus (IFG) and middle frontal gyrus (MFG) showed decreased negative RSFC to MPFC (Fig1 left part). PCC: several DMN regions such as the MPFC, anterior cin- gulate cortex (ACC)and middle temporal gyrus (MTG) had decreased pos- itive RSFC to PCC while bilateral IFG, MFG, and left superior parietal lobular (SPL) belonging to the task-positive network had negative RSFC to PCC (Fig 1 right part). Conclusions: We showed AD-related disruption of RSFC within DMN and between DMN and task-positive networks, pro- viding further evidence for the notion of functional disconnectivity in this disease. IC PLENARY: PL-02 IC-PL-02 IMAGING IN FTD Gil Rabinovici 1 , Howard Rosen 1 , Maria-Luisa Gorno-Tempini 1 , Adam Boxer 1 , Katherine Rankin 1 , Suzee Lee 1 , William Jagust 2 , Joel H. Kramer 1 , Michael Weiner 3 , Bruce Miller 1 , 1 UCSF Memory and Aging Center, San Francisco, California, United States; 2 University of California, Berkeley, Berkeley, California, United States; 3 UCSF, San Francisco, California, United States. Figure 1. Regional t-values on maximum probability brain atlas significant regions (P <0.05, uncorrected) outlined IC Plenary: PL-02 P6