Here’s a quote from a great article about a speech therapist’s experience of visiting a sci-fi fans convention with her sister, Elsie

“She [the speech therapist] saw lots of fans in groups talking.  To her they seemed angry and rude.  To Elise they seemed nothing of the sort.  Observing them more closely, she realized that they were using different social cues, different body language, different eye contact, and even different ways of forming vowels…"

There are lots more observations about body language, ways of signalling that you have finished speaking,and whether it is rude to interrupt.

It's a really interesting read, because the way the fans behave would be unremarkable in many an IT department (and startling if you've wandered in from marketing...)