Limbic Tract Integrity Contributes to Pattern Separation Performance Across the Lifespan.

@article{Bennett2015LimbicTI,
  title={Limbic Tract Integrity Contributes to Pattern Separation Performance Across the Lifespan.},
  author={Ilana J. Bennett and Derek J. Huffman and Craig E. L. Stark},
  journal={Cerebral cortex},
  year={2015},
  volume={25 9},
  pages={
          2988-99
        }
}
Accurate memory for discrete events is thought to rely on pattern separation to orthogonalize the representations of similar events. Previously, we reported that a behavioral index of pattern separation was correlated with activity in the hippocampus (dentate gyrus, CA3) and with integrity of the perforant path, which provides input to the hippocampus. If the hippocampus operates as part of a broader neural network, however, pattern separation would likely also relate to integrity of limbic… 

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References

SHOWING 1-10 OF 89 REFERENCES
Age-related memory deficits linked to circuit-specific disruptions in the hippocampus
TLDR
Evidence for “representational rigidity” in older adults’ dentate/CA3 that is linked to behavioral discrimination deficits is reported and structural and functional alterations in the hippocampal network that predict age-related changes in memory function are highlighted.
Pattern separation deficits associated with increased hippocampal CA3 and dentate gyrus activity in nondemented older adults
TLDR
A behavioral impairment in pattern separation was found in a sample of healthy older adults compared with young controls and a specific functional deficit in the CA3/dentate network contributes to memory difficulties with aging, which is consistent with recent fMRI and behavioral reports in healthy aging.
Pattern separation in the hippocampus
Frontotemporal Connections in Episodic Memory and Aging: A Diffusion MRI Tractography Study
TLDR
It is suggested that degradation of microstructure in the fornix and the uncinate fasciculus make critical but differential contributions to the mechanisms underlying age-related cognitive decline and subserve distinct components of memory.
White matter correlates of cognitive domains in normal aging with diffusion tensor imaging
TLDR
Findings suggest that DTI tractography enables anatomical definition of region of interest (ROI) for correlation of behavioral parameters with diffusion indices, and functionality can be correlated with white matter integrity.
Fornix Microstructure Correlates with Recollection But Not Familiarity Memory
TLDR
The use of diffusion-weighted imaging to investigate whether individual differences in fornix white matter microstructure in neurologically healthy participants were related to differences in memory as assessed by two recognition tasks supported the idea that there are distinct MTL–diencephalon pathways that subserve differing memory processes.
Diffusion tensor imaging of cerebral white matter integrity in cognitive aging.
Cerebral White Matter Integrity and Cognitive Aging: Contributions from Diffusion Tensor Imaging
TLDR
With continued improvements in spatial resolution and integration with functional brain imaging, DTI holds considerable promise, both for theories of cognitive aging and for translational application.
...
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