Sometimes, when hosting a meeting, I find myself laughing through a sentance when there's really nothing funny at all. I wonder to myself "what the hell was that?".
According to this article, it's probably my subconscious/instinct trying to put the audiance at ease or make the subject matter more "playful" than dry business and communicate that "it's OK to communicate freely - you're not going to be reprimanded".
However, that can also have reverse consequences when people subconsciously over-react and interpret that laugh that you think the subject work is a game and not serious, or that your role is a bit of a joke and they don't have to take you seriously. I will definitely keep this in mind going forward and try to control that awkward trait.