Introduction

Stimuli of different modalities can acquire an affective value via evaluative conditioning. This process describes a shift in perceived affective quality of a neutral stimulus towards the hedonics of an associated affective stimulus. The olfactory system, as compared to other modalities, might be especially prone to attributing affective value to an odor due to its close neuroanatomical connectivity with brain regions processing emotion.

Methods

In the present study, we investigated whether perceived affective quality of odors is more sensitive to evaluative conditioning than that of sounds. For this purpose, 48 healthy participants (50% male) rated unfamiliar and emotionally neutral odors and sounds before and after pairing with either aversive or neutral pictures.

Results

Our results show a stronger decrease in odor valence and stronger increases in arousal and dominance ratings for odors paired with aversive compared to neutral pictures. For sounds, ratings of valence, arousal, and dominance were independent of picture emotionality.

Conclusion

Odors appear to be more sensitive to evaluative conditioning than sounds. Our findings extend existing modality comparisons mainly focusing on characteristics of odor-associated memories by specifically looking at affective quality of the odor itself in associative learning.

Implications

Perceived affective quality of a stimulus goes along with the tendency to approach or avoid this stimulus. For odors, it is especially prone to change into an aversive direction. This may have implications for food and fragrance choices but also for the understanding of clinical conditions in which odors become highly aversive, such as post-traumatic stress disorder.

中文翻译：

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气味比声音对评价性条件反射更敏感

介绍

不同形式的刺激可以通过评价性调节获得情感价值。这个过程描述了中性刺激的感知情感质量向相关情感刺激的享乐性的转变。与其他方式相比，嗅觉系统可能特别容易将情感价值归因于气味，因为它与处理情绪的大脑区域具有密切的神经解剖学连接。

方法

在本研究中，我们研究了气味的感知情感质量是否比声音对评价条件更敏感。为此，48 名健康参与者（50% 男性）在与厌恶或中性图片配对之前和之后对不熟悉且情绪中性的气味和声音进行了评分。

结果

我们的结果表明，与中性图片相比，与令人厌恶的气味配对的气味效价有更强烈的下降，而唤醒和优势评级有更强烈的增加。对于声音而言，效价、唤醒度和主导度的评级与图片情感无关。

结论

气味似乎比声音对评价性调节更敏感。我们的研究结果扩展了现有的模态比较，主要关注气味相关记忆的特征，特别是在联想学习中观察气味本身的情感质量。

影响

刺激的感知情感质量与接近或避免该刺激的倾向相关。对于气味来说，特别容易向令人厌恶的方向转变。这可能对食物和香水的选择有影响，也可能对理解气味变得高度厌恶的临床状况有影响，例如创伤后应激障碍。