Department of Psychological Sciences, University of Missouri-Columbia, Columbia, Missouri 65211, USA.
Psychophysiology. 2012 Feb;49(2):178-85. doi: 10.1111/j.1469-8986.2011.01297.x. Epub 2011 Oct 6.
The postauricular reflex (PAR) is anomalous because it seems to be potentiated during positive emotions and inhibited during negative states, unlike eyeblink and other components of the startle reflex. Two evolutionary explanations based on simian facial emotion expressions were tested. Reflexes were elicited while 47 young adult volunteers made lip pursing or grimacing poses and viewed neutral, intimidating, or appetitive photos. The PAR was enhanced during appetitive slides, but only as subjects carried out the lip-pursing maneuver. These results support the nursing hypothesis, which assumes that infant mammals instinctively retract their pinnae while nursing in order to comfortably position the head. Appetitive emotions prime the ear-retraction musculature, even in higher primates whose postauricular muscles are vestigial.
耳后的反射（PAR）是异常的，因为它似乎在积极的情绪中增强，而在消极的状态中受到抑制，这与眨眼和惊跳反射的其他成分不同。我们测试了两种基于灵长类面部表情的进化解释。当 47 名年轻成年志愿者做出撅嘴或做鬼脸的姿势并观看中性、恐吓或开胃的照片时，会引发反射。当观看开胃幻灯片时，PAR 增强，但仅当受试者进行撅嘴动作时。这些结果支持护理假说，该假说假设哺乳动物本能地将其耳廓缩回，以便在哺乳时舒适地定位头部。开胃的情绪使耳部回缩肌肉得到预热，即使是在后耳肌已退化的高等灵长类动物中也是如此。
