New psychology research explores "word aversion," or why "as many as 20% of the population equates hearing the word 'moist' to the sound fingernails scratching a chalkboard." In a scientific paper about their study, psychologists from Oberlin College and Trinity University report that for some people the word "moist" is associated with bodily functions that trigger a visceral feeling of disgust. No surprise there. But interestingly, those "semantic features" of the word may not be the only issue at play. From their paper:
A separate possible explanation not tested in the current studies, but which the author acknowledges, is rooted in the facial feedback hypothesis. This hypothesis suggests that facial movement can influence emotional experience. In other words, if facial muscles are forced to configure in ways that match particular emotional expressions, then that may be enough to actually elicit the experience of the emotion. On this explanation, saying the word "moist" might require the activation of facial muscles involved in the prototypical disgust expression, and therefore trigger the experience of the emotion. This could explain the visceral response of "yuck" people get when they think of the word. Separate research has identified the particular facial muscles involved in the experience and expression of disgust, but no research as of yet has tested whether the same muscles are required when saying "moist."
"An Exploratory Investigation of Word Aversion" (via Scientific American)