{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T17:16:49Z","timestamp":1790443009032,"version":"4.1.0"},"reference-count":74,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T00:00:00Z","timestamp":1593043200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Vetenskapsr\u00e5det","doi-asserted-by":"publisher","award":["2018-02470"],"award-info":[{"award-number":["2018-02470"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"publisher"}]},{"name":"County Council of \u00d6sterg\u00f6tland (Research-ALF)","award":["LIO-700931"],"award-info":[{"award-number":["LIO-700931"]}]},{"name":"County Council of \u00d6sterg\u00f6tland (Research-ALF)","award":["LIO-900631"],"award-info":[{"award-number":["LIO-900631"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>The nociceptive withdrawal reflex (NWR) is used to probe spinal cord excitability in chronic pain states. Here, we used an automated and unbiased procedure for determining the NWR threshold and compared the reflex thresholds and corresponding pain ratings in a well-characterized cohort of fibromyalgia (n = 29) and matched healthy controls (n = 21). Surface electrical stimuli were delivered to the foot in a stepwise incremental and decremental manner. The surface electromyographic activity was recorded from the ipsilateral tibialis anterior muscle. Fibromyalgia patients reported significantly higher scores for psychological distress and pain-related disability and a significantly lower score for perceived state of health compared to the matched controls. The subjective pain ratings were significantly higher in patients. The NWR thresholds were similar to the controls. In the patients, but not in controls, the NWR thresholds and subjective pain ratings were significantly correlated. Our results showed an increased subjective pain sensitivity in fibromyalgia, but we found no evidence for spinal sensitization based on the reflex measures.<\/jats:p>","DOI":"10.3390\/jcm9061992","type":"journal-article","created":{"date-parts":[[2020,6,25]],"date-time":"2020-06-25T10:36:54Z","timestamp":1593081414000},"page":"1992","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Automated Nociceptive Withdrawal Reflex Measurements Reveal Normal Reflex Thresholds and Augmented Pain Ratings in Patients with Fibromyalgia"],"prefix":"10.3390","volume":"9","author":[{"given":"Johannes","family":"Ydrefors","sequence":"first","affiliation":[{"name":"Department of Clinical Neurophysiology, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"},{"name":"Center for Social and Affective Neuroscience, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomas","family":"Karlsson","sequence":"additional","affiliation":[{"name":"Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ulrika","family":"Wentzel Olausson","sequence":"additional","affiliation":[{"name":"Pain and Rehabilitation Centre, Department of Health, Medicine and Caring Sciences, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6396-5104","authenticated-orcid":false,"given":"Bijar","family":"Ghafouri","sequence":"additional","affiliation":[{"name":"Pain and Rehabilitation Centre, Department of Health, Medicine and Caring Sciences, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ann-Charlotte","family":"Johansson","sequence":"additional","affiliation":[{"name":"Center for Social and Affective Neuroscience, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H\u00e5kan","family":"Olausson","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"},{"name":"Center for Social and Affective Neuroscience, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4316-1264","authenticated-orcid":false,"given":"Bj\u00f6rn","family":"Gerdle","sequence":"additional","affiliation":[{"name":"Pain and Rehabilitation Centre, Department of Health, Medicine and Caring Sciences, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8773-8232","authenticated-orcid":false,"given":"Saad S.","family":"Nagi","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurophysiology, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"},{"name":"Center for Social and Affective Neuroscience, Link\u00f6ping University, 58185 Link\u00f6ping, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1113\/jphysiol.1910.sp001362","article-title":"Flexion-reflex of the limb, crossed extension-reflex, and reflex stepping and standing","volume":"40","author":"Sherrington","year":"1910","journal-title":"J. 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