Question: What is the best problem that you have ever solved?

Carolyn McGettigan answered on 18 Jan 2018:

Great question! I’ll pick one example….

In my lab, we try to design experiments to address questions about how human vocal communication.

Recently, together with my colleague Nadine, we asked ourselves how well people might process a person’s identity from listening to their laughter. This was because in one of Nadine’s previous studies, she was playing people clips of laughter alongside photos of happy faces, and some participants complained that there was a mistake – they thought that she had played them women’s voices with photos of men. But she hadn’t made a mistake…. so this got us thinking that maybe we’re good at detecting information about people from their speech, but it’s not so easy from laughter (so, in the previous study maybe people were accidentally thinking that male laughter was coming from a woman).

We set about to test this, and found that our hunch was correct! In particular, people find it much more difficult to accurately perceive a talker’s sex and their individual identity when they are listening to authentic laughter (the kind that you’d produce when something is very, very funny). Through a series of experiments we were able to show that it seems like real, intense laughter doesn’t really convey information about a person’s identity as well as other sounds (including posed laughter). This is a cool finding, because the brain regions associated with real, intense laughter might be those shared with other species (like chimps), whereas when we speak there are additional newer brain regions involved that don’t exist in those species. So, maybe our skills in recognising voices could be more strongly associated with speech, and not necessarily present for all vocal sounds.