they have communications duh

It means that someone got the snot knocked out of them and it got on their helmet

When you type a question, it gives you a list of similar questions. You really should have read those.
BUT...the dots indicate to the officials which helmet has a radio connection with the sidelines, because only one such helmet is allowed on the field at a time.

you know i realy don't know I was wandering that too every QB had them on I don't know about the other players on there teams I hope this helps a little

Radio.

BTW, Smitty: keep up the good work