Aesthetic experience is influenced by causality in biological movements

Yi-Chia Chen (UCLA), Frank Pollick (U of Glasgow), & Hongjing Lu (UCLA)

What makes some body movements look more elegant than others? We examined whether visual properties in movements contribute to the aesthetic experience from seeing actions. To isolate influences of visual features from those of prior knowledge, we created point-light "creatures" by spatially scrambling locations of a point-light walker's 13 joints. Participants rated how aesthetically pleasing and how lifelike each point-light creature looked in a 2-second video of the creature moving from left to right. In Experiment 1 (N=40), the motion trajectories of the joints were either from an upright walker (thus exhibiting gravitational acceleration), or from an inverted walker (thus defying gravity). In Experiment 2 (N=40), in addition to generating creatures from upright or inverted walkers, the trajectories of the joints were either congruent to the direction of global body displacements, or incongruent (as in the moonwalk). Participants gave higher aesthetic ratings for creatures with upright trajectories than those with inverted trajectories, and for creatures with congruent rather than incongruent movements. Animacy ratings yielded similar differences across conditions. Also, the creatures rated as more alive were seen as more aesthetically pleasing, as evidenced by a positive correlation between animacy and aesthetic ratings. However, after regressing out the influence of animacy, participants still found the creatures that move in a natural causal manner (in accordance with gravity and their body displacements) more aesthetically pleasing. The subtlety of different visual properties between conditions suggests a role of automatic perceptual mechanisms in these preferences of causally-natural movements. Thus, while our conscious minds may enjoy watching the magical moonwalk, our automatic minds, with a taste for causality, may curtail the impression of its visual beauty.
Acknowledgements: National Science Foundation (NSF BCS-1655300) to HL.