Effects of distortion of spatial and temporal resolution of video stimuli on emotion attributions

Whether recognition of emotion from facial expression is affected by distortions of pictorial quality has rarely been tested, with the exception of the influence of picture size on emotion recognition. On the other hand, this question is important for (low-cost) tele-communication and tele-conferencing. Here an attempt is made to study whether emotion recognition from facial expression is impaired when video stimuli are distorted both with respect to spatial (pixel) resolution and with respect to temporal resolution (refreshment rate).N=56 stimuli, in which professional actors encoded 14 different emotions, were presented to groups of judges (N=10 in each condition) in six different distortion conditions. Furthermore, judges were confronted with a control condition, presenting the non-distorted stimuli. Channel of information (close-up of the face versus full body recording) was in addition manipulated. Results indicate (besides main effects for type of emotion encoded and for channel) that emotion recognition is impaired by reductions of both spatial resolution and temporal resolution, but that even very low spatial and temporal resolutions result in recognition rates which are still considerably above chance expectation. Results are discussed with respect to the importance of facial expression and body movement in communicating emotions, and with respect to applied aspects concerning tele-communication.