Abstract
Positive serial dependence is a phenomenon where current visual perception is systematically biased towards the immediate past. We previously showed that attractiveness ratings of artworks are assimilated toward the preceding trial (Kim and Alais, VSS 2018). The current study investigates how long it takes to form an aesthetic judgment and for the positive serial dependence to emerge. Each participant viewed 40 artwork images, each presented 20 times in a random order for 250 ms, followed by a noise mask. Participants rated the painting’s attractiveness by adjusting a slide bar on the screen. Results showed that the current painting earned a higher attractiveness rating than its average when it was preceded by a more attractive painting, and vice versa. Interestingly, the mean attractiveness ratings for the stimuli were highly correlated with those from our previous study in which different observers viewed the same paintings for 1 s. Furthermore, we found that paintings with cooler colours were preferred to those with warmer colours in both studies. Unlike the longer duration experiment, however, individual questionnaire data on art interest and knowledge did not correlate with an observer’s magnitude of serial bias. In sum, we found that aesthetic ratings of artworks can be formed surprisingly quickly and are sequentially dependent. The finding that aesthetics ratings obtained using brief, post-masked stimuli correlated well with ratings from different observers given longer viewing times, as well the dependence of ratings on colour in both experiments, suggest that aesthetic judgments are at least partly driven by early perceptual processes. Cognitive sources relevant to art appreciation appear to require a longer time scale, as the dependence on art knowledge and interest seen for 1 s presentations was absent for 250 ms trials.