{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T05:21:02Z","timestamp":1788067262886,"version":"build-2784847793"},"reference-count":88,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2025,8,20]],"date-time":"2025-08-20T00:00:00Z","timestamp":1755648000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000026","name":"National Institute on Drug Abuse","doi-asserted-by":"publisher","award":["K08DA037525"],"award-info":[{"award-number":["K08DA037525"]}],"id":[{"id":"10.13039\/100000026","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000065","name":"National Institute of Neurological Disorders and Stroke","doi-asserted-by":"publisher","award":["R21NS1181162"],"award-info":[{"award-number":["R21NS1181162"]}],"id":[{"id":"10.13039\/100000065","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000065","name":"National Institute of Neurological Disorders and Stroke","doi-asserted-by":"publisher","award":["R01NS127901"],"award-info":[{"award-number":["R01NS127901"]}],"id":[{"id":"10.13039\/100000065","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>The motivational and affective properties of chronic pain significantly impact patients\u2019 lives and response to treatment but remain poorly understood. Most available phenotyping tools of chronic pain affect rely on patients\u2019 self-report. Here we instead directly studied the willingness of chronic low-back pain (CLBP, n\u2009=\u200982) patients to expend effort to win monetary rewards available for wins at different probabilities and different levels of difficulties in comparison to matched pain free controls (n\u2009=\u200943). Consistent with the hypothesis of \u201cnegative hedonic shift\u201d in chronic pain we observed that CLBP patients are significantly less willing than pain free controls to expend effort to go for high cost\/high reward choices and their reported low-back pain intensity predicted increased effort discounting. Patients\u2019 performance was not explained by their self-reported depressive symptoms. Our results present new behavioral evidence characterizing the nature of anhedonia in chronic pain and highlight the importance of recognizing and assessing diminished motivation as an integral component of the chronic pain experience.<\/jats:p>","DOI":"10.1371\/journal.pone.0317980","type":"journal-article","created":{"date-parts":[[2025,8,20]],"date-time":"2025-08-20T17:39:03Z","timestamp":1755711543000},"page":"e0317980","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":4,"title":["Loss of effort in chronic low-back pain patients: Motivational anhedonia in chronic pain"],"prefix":"10.1371","volume":"20","author":[{"given":"Samuel","family":"Alldritt","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammad","family":"Jammoul","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5834-4872","authenticated-orcid":true,"given":"Meena","family":"Makary","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susanne","family":"Becker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1867-6629","authenticated-orcid":true,"given":"Daniel","family":"Maeng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian","family":"Keane","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Zald","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0537-7216","authenticated-orcid":true,"given":"Paul","family":"Geha","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,8,20]]},"reference":[{"key":"pone.0317980.ref001","first-page":"423","article-title":"Sensory, motivational, and central control determinants of pain.","volume-title":"The skin senses","author":"C. 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