Smell &Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany.
Open Value, Paris, France.
Sci Rep. 2017 Jan 25;7:41047. doi: 10.1038/srep41047.
Habituation is a filter that optimizes the processing of information by our brain in all sensory modalities. It results in an unconscious reduced responsiveness to continuous or repetitive stimulation. In olfaction, the main question is whether habituation works the same way for any odorant or whether we habituate differently to each odorant? In particular, whether chemical, physical or perceptual cues can limit or increase habituation. To test this, the odour intensity of 32 odorants differing in physicochemical characteristics was rated by 58 participants continuously during 120s. Each odorant was delivered at a constant concentration. Results showed odorants differed significantly in habituation, highlighting the multifactoriality of habituation. Additionally habituation was predicted from 15 physico-chemical and perceptual characteristics of the odorants. The analysis highlighted the importance of trigeminality which is highly correlated to intensity and pleasantness. The vapour pressure, the molecular weight, the Odor Activity Value (OAV) and the number of double bonds mostly contributed to the modulation of habituation. Moreover, length of the carbon chain, number of conformers and hydrophobicity contributed to a lesser extent to the modulation of habituation. These results highlight new principles involved in the fundamental process of habituation, notably trigeminality and the physicochemical characteristics associated.
习惯化是一种过滤器，它优化了我们大脑在所有感觉模式下处理信息的方式。它导致对连续或重复刺激的无意识反应降低。在嗅觉中，主要的问题是习惯化是否对任何气味都以相同的方式起作用，还是我们对每种气味的习惯化方式不同？特别是，化学、物理或感知线索是否可以限制或增加习惯化。为了检验这一点，32 种具有不同理化特性的气味的强度在 120 秒内由 58 名参与者连续进行评估。每种气味都以恒定浓度输送。结果表明，气味在习惯化方面存在显著差异，突出了习惯化的多因素性。此外，习惯化还可以根据气味的 15 种理化和感知特征进行预测。分析强调了三叉神经的重要性，三叉神经与强度和愉悦度高度相关。蒸气压、分子量、气味活度值（OAV）和双键数主要有助于调节习惯化。此外，碳链长度、构象数和疏水性在较小程度上有助于调节习惯化。这些结果突出了习惯化这一基本过程中涉及的新原则，特别是三叉神经和相关的理化特性。
