Pattern Separation: A Key Processing Deficit Associated with Aging?

  • Paul E. GilbertEmail author
  • Heather M. Holden
  • David P. Sheppard
  • Andrea M. Morris


Age-related memory impairment has been well documented in older adults and may serve as an early indicator of mild cognitive impairment or Alzheimer’s disease in some individuals. The work of Dr. Raymond Kesner has shown that pattern separation is a critical mechanism, supported by the dentate gyrus and CA3 hippocampal subregions, for reducing potential interference among similar memory representations to enhance memory accuracy. A growing literature indicates that pattern separation becomes less efficient with normal aging as a result of age-related changes in the hippocampus and its perforant path input. Researchers have hypothesized that decreased pattern separation efficiency may be a key processing deficit that could contribute to memory impairment associated with aging. In this chapter, we will review studies that have examined age-related changes in pattern separation in humans and rodents. In addition, we will discuss the potential basic science, translational, and clinical implications from these studies to illustrate the need to further examine the relationship between the brain changes associated with aging and pattern separation. The innovative behavioral studies to examine pattern separation conducted in the laboratory of Dr. Raymond Kesner have contributed greatly to our understanding of this mnemonic process and have set the foundation for the behavioral investigation of age-related changes in pattern separation.


Hippocampus Dentate gyrus Aging Episodic memory Interference Pattern separation 



A portion of the research reviewed in the chapter was supported by a National Institutes of Health Grant (#AG034202) from the National Institute on Aging awarded to Paul E. Gilbert. Paul Gilbert would like to thank and acknowledge Dr. Raymond Kesner for being an excellent mentor, collaborator, and friend. Andrea Morris also would like to thank Dr. Kesner for his mentorship, valuable scientific input, and advice. The authors thank Dr. Kesner for his contributions to the field and wish him the best in his retirement.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Paul E. Gilbert
    • 1
    • 2
    Email author
  • Heather M. Holden
    • 2
  • David P. Sheppard
    • 1
    • 3
  • Andrea M. Morris
    • 4
  1. 1.Department of PsychologySan Diego State UniversitySan DiegoUSA
  2. 2.Joint Doctoral Program in Clinical PsychologySan Diego State University—University of California San DiegoSan DiegoUSA
  3. 3.Department of PsychologyUniversity of HoustonHoustonUSA
  4. 4.Department of Health Policy and ManagementUniversity of CaliforniaLos AngelesUSA

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