Abstract
Emotional reactions can be described as a combination of three components: 1. autonomic,
2. behavioral/expressive and 3. cognitive/experiential. The goal of this study was
to characterize the experiential aspect in detail using emotional reactions to faces displaying
emotional expressions. A detailed knowledge about emotional reactions to faces is
necessary, e.g. for functional imaging studies (fMRI or PET) using faces as visual stimuli
and for use in the analysis of communication deficits in psychiatric patients. This study
explored the effects of the following factors: 1. variations of displayed facial affect in
quality (happy vs. sad) and 2. quantity or strength of expressed emotion, 3. presentation
duration (0.5-10sec), 4. repeated presentations and 5. gender of viewer and pictured face.
20 photographs each of happy and sad faces (black-and-white, only face visible, randomised
order, strength of facially expressed emotion varying) were presented to 15
healthy volunteers on a PC-screen. Presentation duration and repetition rate were tested
in two seperate experiments with 10 subjects each. Instruction was to look at the photograph
like one would when seeing the subject in a socially neutral context, e.g. on a bus.
Immediately afterwards the subjects evaluated the induced emotions by marking continous
scales for happiness, sadness, disgust, anger, surprise, fear and insecurity which
were presented on the PC-screen.
Happy faces significantly evoked more happiness and were perceived as more pleasant
than sad faces which highly significantly evoked more sadness. Anger, fear and insecurity
were also more present during the presentation of sad faces but in absolute terms much
less than sadness.
The gender effects were generally much smaller than the effects of depicted emotion.
Significance (p<0.01) was reached for the following: Female subjects significantly experienced
more disgust and fear overall and perceived happy faces as more pleasant and sad
faces as more unpleasant than males. Pictures of females were judged as more pleasant
and evoked more happiness and sadness and less disgust and fear than pictures of males.
There was no significant effect of the strength of the facially expressed emotion and of
the duration of picture presentation. Repeated presentation had a significant effect on surprise
which decreased.
Emotions when perceiving an emotionally expressive face are specific and correspond to
the displayed facial expressions. Perception of happy faces induced happy feelings and
sad faces sadness even within 500ms and with few gender differences. This supports the
hypothesis that the emotional content of facial expressions is decoded non-verbally by
evoking similar emotions in the observer in fast and probably biologically predetermined
neuronal systems.
