Research has shown that there are 6 different types of screams. There are screams out of anger, fear, pain, grief, happiness, and extreme joy. Generally speaking, the first three types of screams are used to signal something alarming, the final three versions are not there to alarm.
What is interesting is that through fMRI scans, participants undertaking a study responded more on a neurological level to the non-alarm screams, than they did for the alarm screams. The researchers theorise that human listeners may tend to respond more quickly, accurately, and with higher neural sensitivity to non-alarm and positive scream calls because these screams “seem to have a higher relevance in human sociobiological interactions.”
This research shows how diverse our communication through screams can be. There used to be the assumption that humans are more wired to react to screams related to danger and alarm, as are primates and other animals, however, through this research it is quite clear that humans react quicker and more efficiently to sounds related more to sociobiological interactions.