认知与发展心理学研究室知识库

嗅觉是进化过程中最古老的感官之一，为人类提供丰富的气味体验。嗅觉障碍不仅影响营养摄入、生活质量和社交互动，甚至可能危及生命安全。尽管嗅觉系统具有一定的可塑性，大多数嗅觉障碍能够自发恢复，但对于无法自发恢复的个体，亟需有效的干预措施。相比药物治疗，嗅觉训练作为一种操作简便且无副作用的干预方法，具备显著的应用潜力。但现有范式多源于西方文化情境，操作依赖线下实验室，研究一构建了一套文化适配、居家可行的嗅觉训练体系并验证其有效性。研究一共收集到 43 位有效被试的数据，结果表明，该训练方法在改善嗅觉功能方面具有应用价值，生态学效度较高，参与者在完成嗅觉训练后，嗅觉灵敏度（阈值）、识别能力确实得到了提升，验证了该训练方案与训练气味集的有效性，且识别分数的增长量显著受训练密度影响，训练越勤快，嗅觉识别能力恢复越多。

嗅觉感知具有显著的个体异质性，表现为不同个体对相同气味的知觉属性及情感反应上的差异。同一气味可能引发不同的嗅觉体验，而不同气味也可能唤起 相似的知觉反应。近年来，虽然研究者通过监测大脑活动探索了嗅觉感知的神经基础，但关于嗅觉感知在个体间的异质性及其神经机制的研究仍然不足。研究二招募了30名女性被试，采用多个气味描述词构建个体的嗅觉知觉空间，并结合脑电图技术，采用表征相似性分析（RSA）探讨了知觉评分与脑电特征之间的对应关系。结果显示在被试内分析中，情绪描述词的知觉矩阵与脑电特征矩阵在群体水平上呈现显著正相关（mean r = 0.0922, p = 0.0289），表明个体内部的感知空间与神经活动模式具有一致性，其中 Beta 频段与情绪描述词知觉矩阵呈现出显著正相关（mean r = 0.0869, p = 0.0188），Gamma 频段与气味属性知觉矩阵亦呈现出一定趋势（mean r = 0.0672, p = 0.0851）。在分电极分析中，左中央区 C5电极的脑电活动与情绪感知空间呈现显著负相关（mean r = -0.0799, p = 0.0109），右中央区 C2 电极与气味属性感知空间呈现显著正相关（mean r = 0.0784, p = 0.0235），右额区 F6 电极在情绪与气味属性两个维度之间的脑电表征存在显著差异（p = 0.0087）。相较之下，被试间的脑电指纹与感知矩阵之间未发现显著一致性。这些观察结果表明不同频带的神经振荡及不同脑区可能分别参与了对嗅觉信息中情感与物理属性的加工与表征，为理解嗅觉个体差异背后的神经机制提供了证据。

Evolutionarily ancient, the olfactory system provides us with rich odor experiences. Olfactory dysfunction adversely affects nutritional intake, quality of life, social interactions, and personal safety. While the olfactory system exhibits plasticity and some dysfunctions gradually resolve over time, effective interventions are essential for those that do not. Compared to pharmacological treatments, olfactory training presents significant potential as a simple intervention with minimal side effects. In Study 1, we developed an olfactory training kit tailored for the Chinese population, along with an online training platform, and applied them to individuals with COVID-related smell loss that persisted for over a month post-infection. Results indicate the effectiveness of the training protocol in real-world settings.

Olfactory perception is highly idiosyncratic, with individuals perceiving the same odorants as possessing distinct qualities and eliciting varied emotional responses. Conversely, different odorants can produce similar perceptual outcomes. While recent studies have begun to uncover the mechanisms underlying olfactory perception, the factors contributing to the idiosyncrasies of our olfactory experiences remain elusive. In Study 2, we characterized individual odor perceptual spaces using various odor descriptors and examined the neural oscillatory correlates of inter-individual differences in the perception of odor quality and hedonic tone. RSA revealed a significant positive correlation between affective appraisals of individual odors and their associated EEG features (mean r = 0.0922, p = 0.0289). Frequency-specific analyses revealed a significant association in the beta band for affective descriptors (mean r = 0.0869, p = 0.0188), and a marginal trend in the gamma band for quality descriptors (mean r = 0.0672, p = 0.0851). RSA conducted at individual electrodes revealed spatially specific effects: affective perception was significantly negatively correlated with EEG patterns at electrode C5 (mean r = -0.0799, p = 0.0109), while odor quality was significantly positively correlated with EEG features at electrode C2 (mean r = 0.0784, p = 0.0235). Additionally, a significant difference was found at electrode F6 between neural representations of affect and quality (p = 0.0087). These findings highlight a within-individual correspondence between olfactory perceptual space and neural space. No such correspondence was observed for either odor quality perception or hedonic perception across participants. These observations provide fresh insights into the neural coding of olfactory perception, suggesting that neural oscillations across distinct frequency bands and cortical regions encode different aspects of olfactory information.