{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T20:19:41Z","timestamp":1790799581418,"version":"4.1.0"},"reference-count":48,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T00:00:00Z","timestamp":1772236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Mild traumatic brain injury (mTBI) is typically associated with transient cognitive disturbance, particularly involving attention and new learning, with most patients demonstrating full recovery within weeks. Memory impairment in uncomplicated mTBI generally reflects reversible neurometabolic dysfunction and is limited to a brief period of post-traumatic amnesia and restricted retrograde loss surrounding the injury. However, a subset of patients develop persistent and disproportionate autobiographical memory disturbance that exceeds expected neuroanatomical limits and lacks structural correlates on neuroimaging. In rare but clinically challenging cases, this presentation may resemble extensive retrograde or identity-related amnesia. This review examines functional (dissociative) amnesia emerging after mTBI and proposes that concussion may act as a gateway condition facilitating the development of Functional Cognitive Disorder (FCD) in vulnerable individuals. We differentiate expected post-traumatic memory patterns from atypical selective impairment of autobiographical retrieval and clarify how distinct memory systems\u2014episodic, autobiographical, semantic, and procedural\u2014are differentially affected. We expand the two-hit hypothesis by integrating contemporary neurobiological evidence. The first hit comprises concussion-induced neurometabolic disturbance, glial activation, oxidative imbalance, and transient fronto-limbic dysregulation. The second hit may involve psychological stress, identity threat, maladaptive metacognitive processes, or persistent neuroinflammatory signalling, collectively resulting in functional inhibition of autobiographical memory retrieval despite preserved memory storage. Functional amnesia is conceptualised as a severe phenotype within the spectrum of functional cognitive disorder. We introduce a structured clinician-administered interview (SIFRA) to operationalise diagnostic features and support systematic assessment. This integrative framework reconciles neurological vulnerability with functional network dysregulation and provides a coherent basis for diagnosis and multidisciplinary management of persistent memory disturbance after mTBI.<\/jats:p>","DOI":"10.3390\/brainsci16030278","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:06:56Z","timestamp":1772460416000},"page":"278","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Mild Traumatic Brain Injury and Functional Amnesia: When Concussion Becomes a Gateway to Functional Cognitive Disorder"],"prefix":"10.3390","volume":"16","author":[{"given":"Ioannis","family":"Mavroudis","sequence":"first","affiliation":[{"name":"Institute of Health Sciences, Leeds University, Leeds LS2 9JT, UK"},{"name":"Third Department of Neurology, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"},{"name":"Academy of Romanian Scientists, 3 Ilfov, 050044 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5617-0346","authenticated-orcid":false,"given":"Foivos","family":"Petridis","sequence":"additional","affiliation":[{"name":"Third Department of Neurology, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alin","family":"Ciobica","sequence":"additional","affiliation":[{"name":"Academy of Romanian Scientists, 3 Ilfov, 050044 Bucharest, Romania"},{"name":"Department of Biology, Faculty of Biology, Alexandru Ioan Cuza University of Iasi, Carol I Avenue 20Th A, 700505 Iasi, Romania"},{"name":"\u201cIoan Haulica\u201d Institute, Apollonia University, Pacurari Street 11, 700511 Iasi, Romania"},{"name":"Center of Biomedical Research, Romanian Academy, Iasi Branch, Teodor Codrescu 2, 700481 Iasi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sotirios","family":"Papagiannopoulos","sequence":"additional","affiliation":[{"name":"Third Department of Neurology, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7319-2045","authenticated-orcid":false,"given":"Dimitrios","family":"Kazis","sequence":"additional","affiliation":[{"name":"Third Department of Neurology, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1080\/16501960410023732","article-title":"Incidence, risk factors and prevention of mild traumatic brain injury: Results of the WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury","volume":"43","author":"Cassidy","year":"2004","journal-title":"J. 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