The results are shown in
Figure 4 plotting the probability of a correct response for the different emotional expressions at the three simulated distances. Descriptive statistics were first computed for each condition and each participant, and all averages were analyzed by repeated-measures analysis of variance using StatView statistical software. The identification rate deteriorated substantially with simulated distance,
F(2, 45) = 49.78,
p < 0.0001. The emotional expressions were correctly identified in 75%, 38%, and 27% of the trials at distances of 30, 60, and 120 cm, respectively. The simulated dynamic emotional expressions were identified to different degrees,
F(3, 135) = 5.68,
p < 0.001. The happy face was identified most often (i.e., on average in 61.5% of the presentations). The other expressions were correctly identified in 41.6%, 38.6%, and 39.7% of the trials for the angry, surprised, and neutral expressions, respectively. Finally, there was a strong interaction between distance and type of emotional expression,
F(6, 135) = 6.52,
p < 0.0001. This is shown in
Figure 4. At the simulated distance of 30 cm, the happy face was correctly identified in 100% of the presentations, the surprised expression was identified in around 75% of the presentations, and the angry expression was identified in around 60% of the presentations. The morphing between the neutral faces was identified in around 55% of the presentations. At 120 cm, the angry face was most often identified (56.3%), and the surprised expression was identified in only 6.3% of the presentations. This is shown in
Figure 4. For all the expressions except for the angry one, the identification rate decreased substantially with simulated distance. For the angry expression, however, the identification rate was significantly higher for the 120-cm distance than for the 60-cm distance,
t(15) = 3.873,
p < 0.001.
Table 1 shows that the higher identification rate for the angry expression at 120 cm is not a question of a general preference for this expression. The other emotional expressions were not confused with the angry one; they were just more difficult to identify.