PDF(Pubmed)
Abstract：
Olfactory training (OT), or smell training,consists of repeated exposure to odorants over time with the intended neuroplastic effect of improving or remediating olfactory functioning. Declines in olfaction parallel declines in cognition in various pathological conditions and aging. Research suggests a dynamic neural connection exists between olfaction and cognition. Thus, if OT can improve olfaction, could OT also improve cognition and support brain function? To answer this question, we conducted a systematic review of the literature to determine whether there is evidence that OT translates to improved cognition or altered brain morphology and connectivity that supports cognition. Across three databases (MEDLINE, Scopus, & Embase), 18 articles were identified in this systematic review. Overall, the reviewed studies provided emerging evidence that OT is associated with improved global cognition, and in particular, verbal fluency and verbal learning/memory. OT is also associated with increases in the volume/size of olfactory-related brain regions, including the olfactory bulb and hippocampus, and altered functional connectivity. Interestingly, these positive effects were not limited to patients with smell loss (i.e., hyposmia & anosmia) but normosmic (i.e., normal ability to smell) participants benefitted as well. Implications for practice and research are provided.
摘要：
嗅觉训练（OT）或者嗅觉训练，包括随着时间的推移反复暴露于气味剂，具有改善或修复嗅觉功能的预期神经可塑性作用。嗅觉下降在各种病理状况和衰老中同时认知下降。研究表明，嗅觉和认知之间存在动态的神经联系。因此，如果OT能改善嗅觉，OT还能改善认知和支持大脑功能吗？要回答这个问题，我们对文献进行了系统回顾,以确定是否有证据表明OT转化为认知功能改善或支持认知功能的脑形态和连通性改变.跨三个数据库(MEDLINE、Scopus,&Embase),本系统综述共发表了18篇文章。总的来说,审查的研究提供了新的证据，表明OT与改善的全球认知有关，特别是,口头流畅性和口头学习/记忆。OT还与嗅觉相关大脑区域的体积/大小增加有关，包括嗅球和海马体,和改变功能连接。有趣的是,这些积极作用不仅限于嗅觉丧失的患者(即，食欲不振和食欲不振)但正常(即，正常的嗅觉能力)参与者也受益。提供了对实践和研究的启示。
