PHOENIX -- Now that she's under cross examination, we're seeing a different side of accused murderer Jodi Arias, says a Valley body language expert.
"It was a totally different body language," Renate Mousseux told 3TV's Javier Soto Friday morning. "She comes across as defiant, as taking the lead. She tells the prosecutor off. She's rather impolite."
While the exact numbers vary, experts agree that a large portion of what we say doesn't come from our mouths. It's comes from non-verbal communication -- body language, gestures, facial expressions, eye contact, blinking, voice quality and speaking style. These are the thing Mousseux looks at and interprets.
When Arias first took the stand, one thing Mousseux noticed was how often she touched her neck.
"Neck touching is when you are in a very uncomfortable situation, when you don't want to be there, when you're stressed out," Mousseux explained. "You have a lot of nerves in your neck, so when you touch it, you kind of relieve your blood pressure. You feel calmer."
Arias had also been constantly touching her hair during her time on the witness stand
"It's a nervous movement," Mousseux said. "She is very uncomfortable, yet her face looks very calm and cold, no expression in her eyes. So these are the other signs where we really can tell how she feels."
It's a different story now that Martinez has started his cross examination. Some say Arias seemed to be almost enjoying the face-off.
"Talk about courtroom drama. She did seem to be enjoying it," criminal defense attorney Julio Laboy. "If you noticed, there was even a runaway smirk from time to time."
Regard of whether she's enjoying herself, Arias seems to be presenting herself quite differently than she did when her lawyers were asking the questions.
"She has no emotions on the left [in the above photo, during questioning by the defense]," Mousseux continued. "On the right, she has emotion. She has facial expressions. She gets lively. ... She sneers. She snickers. ... She has a totally different demeanor."
Martinez will continue his cross examination of Arias Monday.
azfamily.com's Tami Hoey contributed to this report.