{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T05:40:18Z","timestamp":1792388418734,"version":"4.4.0"},"reference-count":58,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"DOI":"10.13039\/100007049","name":"McKnight Brain Research Foundation","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100007049","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R01 AG003376"],"award-info":[{"award-number":["R01 AG003376"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["F32 AG033460"],"award-info":[{"award-number":["F32 AG033460"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000011","name":"Howard Hughes Medical Institute","doi-asserted-by":"publisher","award":["5200006942"],"award-info":[{"award-number":["5200006942"]}],"id":[{"id":"10.13039\/100000011","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The hippocampus integrates spatial information from medial entorhinal cortex (MEC) with non-spatial sensory information from lateral entorhinal cortex (LEC) to form episodic memories. While age-related memory dysfunction is linked to several changes in neuronal function within hippocampal subfields, the effects of aging on MEC and LEC cellular activity patterns are less well-characterized. Here, we investigated MEC and LEC population activity in adult versus aged rats by monitoring the expression of the immediate early gene Arc across two behavioral task sessions with olfactory stimuli separated by a rest period. Aging did not affect the percentage of activated neurons in MEC or their consistent Arc expression patterns across sessions, consistent with stably coding repeated spatial experiences. In contrast, fewer LEC neurons were activated during behavior in aged than adult rats, indicating a specific age-associated hypoactivity in LEC. Additionally, regardless of group, more LEC neurons were activated during the second session compared to the first, which may reflect temporally sensitive LEC neuronal activity increasingly engaged across episodes of experience. These results indicate that aging affects input to the hippocampus in a region-specific manner and are also consistent with observations that suggest that some LEC neurons may provide a temporal tag for episodic memories.<\/jats:p>","DOI":"10.1093\/cercor\/bhag171","type":"journal-article","created":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T04:48:55Z","timestamp":1792385335000},"source":"Crossref","is-referenced-by-count":0,"title":["Age-related differences in behavior-driven activity in LEC but not MEC"],"prefix":"10.1093","volume":"36","author":[{"given":"James P","family":"Lister","sequence":"first","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA , UCLA Path & Lab Med, 10833 Le Conte Ave, 50-094 CHS, Los Angeles, CA, 90095 ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2251-4892","authenticated-orcid":false,"given":"Alison E","family":"Comrie","sequence":"additional","affiliation":[{"name":"Janelia Research Campus, Howard Hughes Medical Institute , 19700 Helix Dr, Ashburn, VA 20147 ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8122-9007","authenticated-orcid":false,"given":"Carol A","family":"Barnes","sequence":"additional","affiliation":[{"name":"Evelyn F. McKnight Brain Institute, University of Arizona , 1333 Martin Ave, Tucson, AZ 85721 ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,10,19]]},"reference":[{"key":"2026101900484651100_ref1","doi-asserted-by":"publisher","first-page":"5280","DOI":"10.1073\/pnas.96.9.5280","article-title":"Age-related defects in spatial memory are correlated with defects in the late phase of hippocampal long-term potentiation in vitro and are attenuated by drugs that enhance the cAMP signaling pathway","volume":"96","author":"Bach","year":"1999","journal-title":"Proc Natl Acad Sci U S A"},{"key":"2026101900484651100_ref2","doi-asserted-by":"publisher","first-page":"74","DOI":"10.1037\/h0077579","article-title":"Memory deficits associated with senescence: a neurophysiological and behavioral study in the rat","volume":"93","author":"Barnes","year":"1979","journal-title":"J Comp Physiol Psychol"},{"key":"2026101900484651100_ref3","doi-asserted-by":"publisher","first-page":"272","DOI":"10.1038\/40859","article-title":"Multistability of cognitive maps in the hippocampus of old rats","volume":"388","author":"Barnes","year":"1997","journal-title":"Nature"},{"key":"2026101900484651100_ref4","doi-asserted-by":"publisher","DOI":"10.18637\/jss.v067.i01","article-title":"Fitting linear mixed-effects models using lme4","volume":"67","author":"Bates","year":"2015","journal-title":"J Stat Softw"},{"key":"2026101900484651100_ref5","volume-title":"The hippocampus book (second)","author":"Burke","year":"2024"},{"key":"2026101900484651100_ref6","doi-asserted-by":"publisher","first-page":"15","DOI":"10.3389\/fnagi.2012.00015","article-title":"Characterizing cognitive aging of recognition memory and related processes in animal models and in humans","volume":"4","author":"Burke","year":"2012","journal-title":"Front Aging Neurosci"},{"key":"2026101900484651100_ref7","doi-asserted-by":"publisher","first-page":"1277","DOI":"10.1002\/hipo.20993","article-title":"Cellular properties of principal neurons in the rat entorhinal cortex II. 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