Age-related memory deficits linked to circuit-specific disruptions in the hippocampus.

ABSTRACT: Converging data from rodents and humans have demonstrated an age-related decline in pattern separation abilities (the ability to discriminate among similar experiences). Several studies have proposed the dentate and CA3 subfields of the hippocampus as the potential locus of this change. Specifically, these studies identified rigidity in place cell remapping in similar environments in the CA3. We used high-resolution fMRI to examine activity profiles in the dentate gyrus and CA3 in young and older adults as stimulus similarity was incrementally varied. We report evidence for "representational rigidity" in older adults' dentate/CA3 that is linked to behavioral discrimination deficits. Using ultrahigh-resolution diffusion imaging, we quantified both the integrity of the perforant path as well

SUBMITTER: Yassa MA 

PROVIDER: S-EPMC3102362 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature