Virtual characters are used extensively in movies and games, but the effect of both motion and body shape on the portrayal of basic human emotions remains poorly understood. Some suggest that the more anthropomorphic a virtual character is, the more eerily nonhuman its emotions may be perceived. Is it possible that the use of virtual characters is counterproductive for conveying emotions? This is an important question for games and movies, as well as virtual reality applications such as training and therapy.

The authors capture the motions of a human actor expressing six basic emotions: sadness, happiness, surprise, fear, anger, and disgust. Then, they use motion capture to animate five virtual body shapes: a low-resolution virtual counterpart, a high-resolution one, a cartoon-like character, a wooden mannequin, and a zombie-like character. Facial and hand motions are blurred, in order to focus the results on the effects of body shape and motion.

Study participants were asked how intensely they thought an animation or the human actor portrayed each of 41 different emotions. The results confirm the usefulness of virtual characters in portraying emotions, an important finding for perception researchers. They also show that motion alone is less effective in the portrayal of emotion than form and motion together.

Finally, because no difference in emotion perception was found between the zombie and the real human (or the other characters), the authors suggest that this is an indication that facial expressions and/or hand motions--rather than body motion and shape--may cause reactions of eeriness.

The main beneficiaries of this research are those in the computer animation and virtual reality communities. The questions raised in this study can also lead to more findings from those studying human psychology.