[johnsmith4739]

You are right in being skeptical.

First, behavioural responses vary from person to person and from culture to culture (Americans will smile in most social situations, Russians don't smile unless there is a laughter coming in).

Second, we are far from associating an internal subjective experience (joy) to an external objective behaviour (smile). It's actually one of the greatest challenges in psychology today. Also, how do you gauge my level of happiness compared to yours?

Third, the whole article is superficial and they don't hide it: first they measure who smiles more ... then they jump to the conclusion - all bronze winners perform the same cognition. Pure speculation.

Even if smiles would denote an emotional episode (joy) it would have to be right in the moment of the emotional episode - and it would be a micro expression (under one second).

Quote: "they studied medal stand photographs" -> posed circumstances.