Distinct MRI atrophy patterns in autopsy-proven Alzheimer's disease and frontotemporal lobar degeneration.

Memory and Aging Center, University of California, San Francisco, California 94143, USA.
American Journal of Alzheimer s Disease and Other Dementias (Impact Factor: 1.43). 01/2008; 22(6):474-88. DOI: 10.1177/1533317507308779
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ABSTRACT To better define the anatomic distinctions between Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD), we retrospectively applied voxel-based morphometry to the earliest magnetic resonance imaging scans of autopsy-proven AD (N = 11), FTLD (N = 18), and controls (N = 40). Compared with controls, AD patients showed gray matter reductions in posterior temporoparietal and occipital cortex; FTLD patients showed atrophy in medial prefrontal and medial temporal cortex, insula, hippocampus, and amygdala; and patients with both disorders showed atrophy in dorsolateral and orbital prefrontal cortex and lateral temporal cortex (P(FWE-corr) < .05). Compared with FTLD, AD patients had decreased gray matter in posterior parietal and occipital cortex, whereas FTLD patients had selective atrophy in anterior cingulate, frontal insula, subcallosal gyrus, and striatum (P < .001, uncorrected). These findings suggest that AD and FTLD are anatomically distinct, with degeneration of a posterior parietal network in AD and degeneration of a paralimbic fronto-insular-striatal network in FTLD.

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Available from: Stephen C Allison, May 20, 2014
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    • "the associated frontal circuit in comparison to other neurodegenerative conditions (Rabinovici et al., 2007). Grossman et al. (2010) examined the interpretation of positive and negative situations in individuals with bvFTD and found that these individuals were particularly impaired in interpreting negative consequences of a social situation (e.g., " rolling through a red light at 2 a.m. when there is a police car at the intersection , " p. 5). "
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    ABSTRACT: Apathy, a reduction in goal-directed behavior (GDB), affects 90% of individuals with behavioral variant frontotemporal degeneration, which is a common cause of early onset neurodegenerative disease. The cognitive and neural impairments associated with apathy make it difficult to initiate, plan, and self-motivate activities toward a specific goal, such as dressing or bathing. These impairments are associated with significant decline in functional ability, caregiver burden, and increased cost of care due to early institutionalization. The current article reviews the evidence suggesting that apathy arises from the interruption of one or any combination of three GDB processes: initiation, planning, and motivation. From this perspective, three subtypes of apathy related to dysfunction at the level of GDB and the corresponding neuroanatomy are explored. Further research is required to confirm and measure these subtypes of apathy for use in clinical and research settings. A more precise classification of apathy by subtype will allow implementation of the most appropriate person-centered, individualized therapy. [Journal of Gerontological Nursing, xx(x), xx-xx.].
    Journal of Gerontological Nursing 09/2014; 40(10):1-8. DOI:10.3928/00989134-20140827-01 · 0.62 Impact Factor
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    • "Aberrant projections from hippocampus and/or MTL could influence frontal cortex function prior to ADrelated anatomical changes. Pathology in mild AD is thought to be limited to the temporo-parietal junction (Rabinovici et al., 2007), which does not include the PEFs, so a lack of impairment in prosaccade generation is not surprising. It has been shown previously that volumetric changes in the SEF correlate with antisaccade latency, but that DLPFC and FEF volume were not correlated with antisaccade performance (Boxer et al., 2006), supporting the notion that functional changes probably precede anatomical changes in the frontal cortex of AD patients. "
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    European Journal of Neuroscience 06/2014; 39(11). DOI:10.1111/ejn.12617 · 3.67 Impact Factor
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    • "Second, the diagnosis of bvFTD was not confirmed pathologically in this group (all are still living). Impairments in self-monitoring likely represent the specific neuroanatomical involvement in bvFTD rather than the neuropathology per se, as prior studies have indicated that patients with pathological or imaging evidence of AD pathology still show the behavioral signs of bvFTD if brain regions normally affected in bvFTD are involved (Rabinovici, Furst, et al., 2007 "
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