As the Austin communication professor at University of Texas research, released in the December 2009 issue of Communication Research, found any social network’s avatar can considerably affect the user's thoughts. 

In the first study to use avatars to prime negative responses in a desktop virtual setting demonstrated that the subtext of an avatar's appearance can simultaneously prime negative thoughts and inhibit positive thoughts inconsistent with the avatar's appearance.

In two separate experiments, research participants were randomly assigned a dark- or white-cloaked avatar, or to avatars wearing physician or Ku Klux Klan-like uniforms or a transparent avatar. So, the participants were assigned tasks including writing a story about a picture, or playing a video game on a virtual team and then coming to consensus on how to deal with infractions.

Participants represented by an avatar in a dark cloak or a KKK-like uniform demonstrated negative or anti-social behavior in team situations and in individual writing assignments.

Previous studies have demonstrated these uniform types to have negative effects on people's behaviors in face-to-face interactions as well. 

That happens as communicating virtually users associate their online interlocutor with a person in a real world. 

"When you step into a virtual environment, you can potentially become 'Mario' or whatever other character you are portraying," said Jorge Peña, assistant professor in the College of Communication, who studies how humans think, behave and feel online. "Oftentimes, the connotations of our own virtual character will subtly remind us of common stereotypes, such as 'bad guys wear black or dress up in hooded robes.' This association may surreptitiously steer users to think and behave more antisocially, but also inhibit more pro-social thoughts and responses in a virtual environment."