Judgment of emotional nonlinguistic vocalizations: age-related differences

Humans make extensive use of vocal information to attribute emotional states to other individuals. To date, most studies exploring perception of vocal emotions have done so in the context of speech prosody, although nonlinguistic emotional vocalizations represent an important, perhaps more universal, means to express emotions. Here, we explored the perception of emotional nonlinguistic vocalizations in healthy individuals, with an emphasis on potential age- and sex-related differences. Sixty participants rated 563 positive (e.g., laughs, sexual vocalizations), negative (e.g., cries, screams of fear), and neutral vocalizations (e.g., coughs), according to the valence, intensity, and authenticity of the emotion expressed. Ratings were consistent among individuals, suggesting that valence is an adequate measure of emotional categorization. An important effect of age emerged: (a) age by vocalization category interactions were observed for both valence and intensity ratings, and (b) younger participants rated stimuli as more emotional than older individuals (i.e., higher valence for positive, lower for negative, and more intense for both positive and negative). We also found a sex effect in the authenticity ratings: older women rated the vocalizations as less authentic than younger women whereas authenticity judgments did not differ between the two age groups in men. Taken together, these findings suggest that, as previously observed for facial expressions and prosody, the judgments of emotional vocalizations may vary with age.