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Methods: A total of 38 MCI outpatients were randomly assigned to OT or a control training condition, which were performed twice a day for 4 months. Olfactory testing, comprehensive neuropsychological assessment, and a passive odor perception task based on magnetic resonance imaging were performed before and after training. Results: The results suggested that OT exhibited no significant effect on olfaction and cognitive function. Additionally, OT exhibited a positive effect on frontal lobe activation (left middle frontal gyrus and orbital-frontal cortex) but exhibited no effect on grey matter volume. Moreover, the change of olfactory scores was positively associated with the change of frontal activation. Conclusion: OT was found to have a limited effect on olfaction and cognition in patients with MCI compared to a non-OT condition but increased their functional response to odors in frontal area.<\/jats:p>","DOI":"10.3233\/jad-215257","type":"journal-article","created":{"date-parts":[[2021,11,30]],"date-time":"2021-11-30T16:57:39Z","timestamp":1638291459000},"page":"745-754","source":"Crossref","is-referenced-by-count":41,"title":["The Effect of Olfactory Training on Olfaction, Cognition, and Brain Function in Patients with Mild Cognitive Impairment"],"prefix":"10.1177","volume":"85","author":[{"given":"Ben","family":"Chen","sequence":"first","affiliation":[{"name":"Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany"},{"name":"Department of Geriatric Psychiatry, Memory Clinic, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, Guangdong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melanie","family":"Espin","sequence":"additional","affiliation":[{"name":"Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Haussmann","sequence":"additional","affiliation":[{"name":"Department of Psychiatry and Psychotherapy, TU Dresden, Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claudia","family":"Matthes","sequence":"additional","affiliation":[{"name":"Department of Psychiatry and Psychotherapy, TU Dresden, Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Donix","sequence":"additional","affiliation":[{"name":"Department of Psychiatry and Psychotherapy, TU Dresden, Dresden, Germany"},{"name":"Deutsches Zentrum f\u00fcr Neurodegenerative Erkrankungen e.V. 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