Article

Hemispheric differences in hippocampal volume predict verbal and spatial memory performance in patients with Alzheimer's disease

Department of Neurological Sciences, Rush University, Chicago, Illinois, USA.
Hippocampus (Impact Factor: 4.16). 01/2000; 10(2):136-42. DOI: 10.1002/(SICI)1098-1063(2000)10:2<136::AID-HIPO2>3.0.CO;2-J
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ABSTRACT

Atrophy of the hippocampal formation, a region important for the acquisition of new declarative knowledge, has been well-documented in Alzheimer's disease (AD), although the relation of such atrophy to the extent of memory dysfunction in these patients has been less clear. In the present study, 18 patients with a clinical diagnosis of probable AD were studied with a high-resolution, quantitative magnetic resonance imaging (MRI) protocol, as well as the verbal and spatial versions of the Buschke controlled learning task. The volumes of the hippocampal formation and, as a control for generalized atrophy, parahippocampal gyrus and temporal neocortex were computed from gapless coronal slices taken perpendicular to the long axis of the hippocampus. To correct for individual differences in brain size, volumes of regions of interest were divided by total intracranial volume. Separate stepwise regression analyses (with age, right and left hippocampal, parahippocampal gyrus, and temporal lobe volumes as the independent variables) showed that left hippocampal volume was the best predictor of free recall and delayed free recall of verbal information (P = 0.0042 and P < 0.0001, respectively). Recall and delayed recall of the spatial location of verbal items were best predicted by right hippocampal volume (P = 0.0054 and P = 0.0118, respectively). Memory scores did not correlate either with parahippocampal gyrus or temporal lobe volume. Furthermore, the relation between hippocampal volume and memory function observed in cases with AD did not hold for healthy aged control subjects.

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Available from: Bradford Dickerson, Jan 21, 2014
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    • "Episodic memory dysfunction represents a hallmark feature of this patient group, in light of the characteristic medial temporal lobe degeneration evident from an early stage in the pathological process (Braak & Braak, 1991). An amnestic profile predominates whereby AD patients exhibit anterograde episodic memory difficulties concerning the encoding and retrieval of recent experiences, irrespective of task modality (McKhann et al., 2011; de Toledo-Morrell et al., 2000). Retrograde memory impairments are also prominent, manifesting in pronounced autobiographical memory dysfunction (Barnabe, Whitehead, Pilon, Arsenault-Lapierre, & Chertkow, 2012; Irish, Hornberger, et al., 2011, Irish, Lawlor, O'Mara, & Coen, 2011), which is significantly associated with the degree of medial and lateral temporal lobe atrophy (Gilboa et al., 2005). "
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    No preview · Article · Apr 2014 · Human Brain Mapping
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    • "Recent studies point to the preferential accumulation of amyloid deposits in specific nodes of the core ABM network in AD, most notably the posterior cingulate cortex and the anteromedial prefrontal cortex (Buckner et al., 2008). Clinically, AD patients typically present with an amnestic profile in which anterograde episodic memory difficulties concerning the encoding and retrieval of recent events are prominent (de Toledo-Morrell et al., 2000; McKhann et al., 2011). This disruption to episodic memory emerges as a consequence of the neuropathological process (neurofibrillary tangles and amyloid deposition), which affects the entorhinal cortex and hippocampus of the medial temporal lobes, and spreads to the neocortex (Ewers et al., 2011; Sperling et al., 2011). "
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