How can you tell if someone is happy? A happy person might laugh or say that they feel happy, but the brain is more quickly able to interpret one of these responses than the other. A study from McGill University evaluated how quickly the brain identifies emotions based on sounds. The findings demonstrate that it is faster and simpler to identify emotions based on non-verbal vocalizations like laughter than based on speech sounds.
The researchers focused their study on three emotions: anger, happiness, and sadness. They tested 24 participants, playing vocalizations with different emotional intent. Some of the vocalizations were non-verbal, like growls, laughs, or sobs. Other vocalization used speech-like nonsense words. The participants were asked to identify which emotion each sound conveyed. While they did this, the researchers monitored their brain activity using EEG. This allowed the researchers to determine how the brain responds to emotional sounds.
The brain is more responsive to emotional vocalizations than to emotional speech sounds. It took only one-tenth of a second for the brain to recognize emotions from vocalizations, less time than it took to identify emotions based on speech. The participants detected vocalizations of happiness more quickly than sounds conveying anger or sadness. Angry vocalizations and speech sounds produced the most brain activity out of the three emotions. The research also demonstrated that more anxious participants responded more quickly and intensely to emotional voices than less anxious participants did.
The researchers posit that the brain reacts faster to vocalizations than to speech because decoding speech is a more complex task that requires more brain areas. The findings may aid researchers in understanding how people process emotions.
This research is published in the journal Biological Psychology.