According to a new study published in the journal PLOS Biology, human screams can convey much more than fear, and they are more acoustically diverse than previously thought.
Functional magnetic resonance imaging
In the study, twelve participants were asked to vocalize positive and negative cries that could be triggered by various situations. A different group of individuals assessed the emotional nature of the screaming, categorized the screaming into different categories, and underwent functional magnetic resonance imaging (fMRI) while listening to the screaming.
The results revealed six psychoacoustically different types of screaming, indicating pain, anger, fear, pleasure, sadness, and joy.
Perhaps most surprisingly, listeners responded faster and more accurately, and with greater neural sensitivity, to positive, unarmed cries than to alarming cries. Specifically, the less alarming screams elicited more activity in many auditory and frontal brain regions.
According to the authors, these results show that cries are more diverse in their communicative and signaling nature in humans than is often assumed.