{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"medRxiv"}],"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:17:17Z","timestamp":1785403037256,"version":"3.56.0"},"posted":{"date-parts":[[2026,6,17]]},"group-title":"Neurology","reference-count":24,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T00:00:00Z","timestamp":1781654400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/"}],"funder":[{"award":["1R01AG053961"],"award-info":[{"award-number":["1R01AG053961"]}],"id":[{"id":"https:\/\/ror.org\/049v75w11","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,6,17]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                <jats:sec>\n                  <jats:title>Objectives<\/jats:title>\n                  <jats:p>Poor sleep quality is a risk factor for Alzheimer\u2019s disease (AD). Older African Americans experience disproportionately high rates of sleep disturbance and AD. Medial temporal lobe (MTL) flexibility reflects dynamic neural reorganization and may be a marker of generalization performance. This study examined whether sleep quality moderates the association between MTL flexibility and memory generalization.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Fifty older African Americans (MeanAge=69.7\u00b16.21 years; 80% women) underwent rs-fMRI to quantify MTL flexibility, Rutgers Acquired Equivalence Task for memory generalization, and Pittsburgh Sleep Quality Index for sleep quality.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>\n                    Greater MTL flexibility was associated with better generalization (r=0.367, p=.017). Good sleepers showed higher MTL flexibility (F\n                    <jats:sub>(1,44)<\/jats:sub>\n                    =8.11, \u03b7p\n                    <jats:sup>2<\/jats:sup>\n                    =.156, p=.007) and superior generalization (F\n                    <jats:sub>(1,46)<\/jats:sub>\n                    = 12.33, \u03b7p\n                    <jats:sup>2<\/jats:sup>\n                    =.211, p=.001). Sleep quality significantly moderated the MTL flexibility\u2013generalization relationship (\u03b2=\u22121.519, p=.012).\n                  <\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Preserved MTL flexibility may confer generalization only in good sleepers, suggesting that sleep disturbance may disrupt the MTL neural resilience among older African Americans.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>WHAT WAS KNOWN<\/jats:title>\n                  <jats:p>Prior research has established that poor sleep quality is associated with increased Alzheimer\u2019s disease (AD) risk, hippocampal dysfunction, and impaired memory. Studies also show that medial temporal lobe (MTL) network dynamics, including flexibility, support key features of cognition including memory generalization. However, limited work has examined how sleep quality interacts with neural flexibility to influence cognition, particularly in older African Americans, a population at elevated risk for both sleep disturbance and AD.<\/jats:p>\n                <\/jats:sec>\n                <jats:sec>\n                  <jats:title>WHAT THIS STUDY ADDS<\/jats:title>\n                  <jats:p>This study demonstrates that sleep quality significantly moderates the relationship between MTL flexibility and memory generalization. While greater MTL flexibility is associated with better generalization, this benefit is evident only among individuals with good sleep quality. These findings suggest that sleep disruption may impair the functional expression of neural resilience mechanisms, even when underlying network flexibility is preserved.<\/jats:p>\n                <\/jats:sec>","DOI":"10.64898\/2026.06.15.26355704","type":"posted-content","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:45:19Z","timestamp":1781743519000},"source":"Crossref","is-referenced-by-count":0,"title":["Preserved Medial Temporal Lobe Flexibility Predicts Memory Generalization Only in the Context of Good Sleep Quality among Older African Americans"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-8579-711X","authenticated-orcid":false,"given":"Payton","family":"White","sequence":"first","affiliation":[{"name":"Center for Molecular & Behavioral Neuroscience, Rutgers University\u2013Newark, 197 University Ave., Suite 209, Newark, NJ 07102 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0552-8464","authenticated-orcid":false,"given":"Miray","family":"Budak","sequence":"additional","affiliation":[{"name":"Center for Molecular & Behavioral Neuroscience, Rutgers University\u2013Newark, 197 University Ave., Suite 209, Newark, NJ 07102 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6314-4074","authenticated-orcid":false,"given":"Soodeh","family":"Moallemian","sequence":"additional","affiliation":[{"name":"Center for Molecular & Behavioral Neuroscience, Rutgers University\u2013Newark, 197 University Ave., Suite 209, Newark, NJ 07102 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8412-1023","authenticated-orcid":false,"given":"Bernadette A.","family":"Fausto","sequence":"additional","affiliation":[{"name":"Department of Health Science & Clinical Practice, Thomas Jefferson University, 130 South Ninth Street Philadelphia, PA 19107 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0538-2303","authenticated-orcid":false,"given":"Mark A.","family":"Gluck","sequence":"additional","affiliation":[{"name":"Center for Molecular & Behavioral Neuroscience, Rutgers University\u2013Newark, 197 University Ave., Suite 209, Newark, NJ 07102 USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026061920051070000_2026.06.15.26355704v1.1","doi-asserted-by":"publisher","DOI":"10.1038\/s41386-019-0432-6"},{"key":"2026061920051070000_2026.06.15.26355704v1.2","doi-asserted-by":"publisher","DOI":"10.5665\/sleep.6240"},{"key":"2026061920051070000_2026.06.15.26355704v1.3","doi-asserted-by":"publisher","DOI":"10.1093\/brain\/awx148"},{"key":"2026061920051070000_2026.06.15.26355704v1.4","doi-asserted-by":"publisher","DOI":"10.1186\/s40035-023-00340-6"},{"key":"2026061920051070000_2026.06.15.26355704v1.5","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/zsac135"},{"key":"2026061920051070000_2026.06.15.26355704v1.6","doi-asserted-by":"publisher","DOI":"10.1002\/alz.12822"},{"key":"2026061920051070000_2026.06.15.26355704v1.7","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/24.8.926"},{"key":"2026061920051070000_2026.06.15.26355704v1.8","doi-asserted-by":"publisher","DOI":"10.1038\/s43856-023-00333-6"},{"key":"2026061920051070000_2026.06.15.26355704v1.9","doi-asserted-by":"publisher","DOI":"10.1093\/brain\/awad232"},{"key":"2026061920051070000_2026.06.15.26355704v1.10","doi-asserted-by":"publisher","DOI":"10.1177\/089198870201500206"},{"key":"2026061920051070000_2026.06.15.26355704v1.11","doi-asserted-by":"publisher","DOI":"10.1007\/s12017-009-8109-7"},{"key":"2026061920051070000_2026.06.15.26355704v1.12","doi-asserted-by":"publisher","DOI":"10.1016\/j.neuron.2023.03.005"},{"key":"2026061920051070000_2026.06.15.26355704v1.13","doi-asserted-by":"publisher","DOI":"10.1016\/j.neuron.2013.12.025"},{"key":"2026061920051070000_2026.06.15.26355704v1.14","doi-asserted-by":"publisher","DOI":"10.1016\/j.dadm.2018.09.003"},{"key":"2026061920051070000_2026.06.15.26355704v1.15","doi-asserted-by":"publisher","DOI":"10.1016\/0165-1781(89)90047-4"},{"key":"2026061920051070000_2026.06.15.26355704v1.16","doi-asserted-by":"publisher","DOI":"10.1093\/sleep\/14.4.331"},{"key":"2026061920051070000_2026.06.15.26355704v1.17","doi-asserted-by":"publisher","DOI":"10.1007\/s00018-007-6457-8"},{"key":"2026061920051070000_2026.06.15.26355704v1.18","doi-asserted-by":"publisher","DOI":"10.3389\/fnagi.2021.746236"},{"key":"2026061920051070000_2026.06.15.26355704v1.19","doi-asserted-by":"publisher","DOI":"10.1016\/j.conb.2017.02.005"},{"key":"2026061920051070000_2026.06.15.26355704v1.20","doi-asserted-by":"publisher","DOI":"10.1038\/s41539-024-00276-0"},{"key":"2026061920051070000_2026.06.15.26355704v1.21","doi-asserted-by":"publisher","DOI":"10.1002\/hbm.70362"},{"key":"2026061920051070000_2026.06.15.26355704v1.22","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-019-55452-9"},{"key":"2026061920051070000_2026.06.15.26355704v1.23","doi-asserted-by":"publisher","DOI":"10.1016\/j.yfrne.2017.02.004"},{"key":"2026061920051070000_2026.06.15.26355704v1.24","doi-asserted-by":"publisher","DOI":"10.7759\/cureus.84232"}],"container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.64898\/2026.06.15.26355704","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,20]],"date-time":"2026-06-20T03:05:28Z","timestamp":1781924728000},"score":1,"resource":{"primary":{"URL":"http:\/\/medrxiv.org\/lookup\/doi\/10.64898\/2026.06.15.26355704"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,17]]},"references-count":24,"URL":"https:\/\/doi.org\/10.64898\/2026.06.15.26355704","relation":{},"subject":[],"published":{"date-parts":[[2026,6,17]]},"subtype":"preprint"}}