Representational momentum is domain-general: Evidence from brightness

A classic finding in visual cognition is “representational momentum”. Show people a photo of a wave crashing on the beach and they are prone to confuse it with a photo taken a moment later. Abruptly mask a video of a rotating shape or a rapidly melting ice cube and people will overestimate how far they saw the shape rotate or the ice melt. Anticipated motion affects what we see, or at least what we remember seeing. Prior research has argued that representational momentum is strictly limited to anticipated motion, in part by appealing to experiments that found no representational momentum for changes in brightness. Here, we refute this claim with new evidence. In five experiments, we demonstrate that richer stimuli and a more sensitive task reveal people to experience representational momentum for changes in brightness. Participants watched animations of a stationary, achromatic shape that increased in brightness before being masked. Using a slider, they selected a specific frame from each animation to indicate precisely how bright they thought the shape was when it disappeared. Participants reliably judged the shape to have been brighter than what they had truly been shown. We found analogous representational momentum effects for darkening shapes, the brightness of chromatic stimuli, and—generalizing our results beyond 2D shapes—the brightness of the ambient light illuminating a 3D object in a computer-rendered scene. These findings are unlikely to be an artifact of the task design because representational momentum for brightness replicated in a 2AFC version of the task and, most importantly, no analogous effects were observed for changes in hue, which are less intuitively directional and predictable. These results suggest representational momentum is a domain-general phenomenon related to anticipatable change, not one that is narrowly limited to motion. The mind actively anticipates changes in many perceptual domains.