Smell and Taste Clinic, Department of Otorhinolaryngology, Technical University of Dresden, Fetscherstrasse, Dresden, Germany.
Department French National Institute for Agricultural Research, Centre des Sciences du Goût et de l'Alimentation (CSGA), Dijon, France.
Chem Senses. 2021 Jan 1;46. doi: 10.1093/chemse/bjaa080.
Olfactory habituation corresponds to a decreased behavioral or perceptual response to an odor after a prolonged exposure to this odor. Our aim was to investigate whether long-term olfactory habituation and its recovery are similar in young (<35 years old) and older adults (>50). Fifty-seven participants were recruited for a 5-week longitudinal study. They were exposed to one of the two odors (manzanate alpha [MA], irone alpha [IA]) for 2 weeks at home. Olfactory detection thresholds for both odors were measured before and after exposure. Results showed that the two age groups behaved similarly. The long-term exposure to an odor led to a temporary increase of its detection threshold (lower sensitivity to the odor). IA thresholds were more sensitive to the duration of exposure with the odor than MA thresholds. One week after termination of exposure, participants fully recovered and even became more sensitive to both odors. No cross-habituation was found between the two odors. Our findings highlight that long-term habituation is specific to the odor exposed, behaves the same in young and older adults, and is fully reversible in both age groups after 1 week.
嗅觉习惯化是指在长时间接触某种气味后，对该气味的行为或感知反应会减弱。我们的目的是研究年轻人（<35 岁）和老年人（>50 岁）的长期嗅觉习惯化及其恢复是否相似。57 名参与者被招募参加为期 5 周的纵向研究。他们在家中接触两种气味（苹果酸盐 α [MA]、铁酮 α [IA]）中的一种，持续 2 周。在暴露前后测量了两种气味的嗅觉检测阈值。结果表明，两个年龄组的行为相似。长期接触一种气味会导致其检测阈值暂时升高（对气味的敏感性降低）。IA 阈值对气味暴露时间的敏感性高于 MA 阈值。暴露结束后一周，参与者完全恢复，甚至对两种气味的敏感性都有所提高。两种气味之间没有交叉习惯化。我们的发现强调了长期习惯化是针对暴露的气味特异性的，在年轻人和老年人中表现相同，并且在 1 周后在两个年龄组中都是完全可逆的。
