Summary: Human brains can do more than simply imagine the presence of nonexistent objects. Our minds can automatically create well-defined representations of objects that are merely implied rather than seen, like the obstacles in a mime’s performance. These findings could aid in the development of artificial intelligence related to vision and navigation by helping understand how humans perceive and navigate their environments.
When we watch a mime seemingly pull on a rope, stumble over an obstacle, or push against the sides of a transparent box, we don’t struggle to recognize the implied objects—our minds automatically construct vivid representations of them, even though they are not actually seen.
To explore how the mind processes and identifies these fictitious objects, researchers brought the art of miming into the lab. Their results reveal that humans mentally represent invisible, implied surfaces both rapidly and automatically.
“Most of the time, we know which objects are around us because we can just see them directly. But what we explored here was how the mind automatically builds representations of objects that we can’t see at all but that we know must be there because of how they are affecting the world,” said Chaz Firestone, an assistant professor who directs Johns Hopkins University’s Perception & Mind Laboratory and the senior author on a paper published in the journal Psychological Science. “That’s basically what mimes do. They can make us feel like we’re aware of some object just by seeming to interact with it.”
To study this phenomenon, Firestone and his colleagues had a group of 360 participants watch clips in which Firestone himself mimed colliding with a wall and stepping over a box in a way that suggested those objects were there, only invisible.
Afterward, a black line appeared in the spot on the screen where the implied surface would have been. This line could be horizontal or vertical, so it either matched or didn’t match the orientation of the surface that had just been mimed. Participants had to quickly identify the line’s orientation. The researchers found that people responded significantly faster when the line aligned with the mimed wall or box, suggesting that the implied surface was already represented in their minds—so much so that it affected their responses to the visible surface they saw immediately after.
Participants had been told not to pay attention to the miming, but they couldn’t help but be influenced by those implied surfaces, said first author Pat Little, who helped conduct the research as an undergraduate at Johns Hopkins and is now a graduate student at New York University.
“Very quickly people can realize that the mime is misleading them and that there is no actual connection between what the person does and the type of line that appears,” Little said. “But even if they think, ‘I should ignore this thing because it’s getting in my way,’ they can’t. That’s the key. It seems like our minds can’t help but represent the surface that the mime is interacting with—even when we don’t want to.”
The work is partly inspired by a phenomenon in psychology called the Stroop effect, which emerges when the name for one color is written in ink of a different color—for example, the word “red” is written in blue ink. When a person is tasked with saying the color of the ink (blue), they can’t help but read the mismatched text (“red”), which distracts them and slows them down. In this regard, miming is like the written word: Just as you can’t help but read the text you see, even when you’re supposed to ignore it, you can’t help but recognize the object being mimed, even when that gets in the way of another task.
Although the findings suggest that our brains imagine these objects automatically, the researchers maintain that mimes still deserve credit.
“This suggests that miming might be different from other kinds of acting,” Little said. “If the mime is skilled enough, understanding what’s going on doesn’t require any effort at all—you just get it automatically.”
“If you’re trying to build a self-driving car that can see the world and steer around objects, you want to give it all the best tools and tricks,” Firestone said. “This study suggests that, if you want a machine’s vision to be as sophisticated as ours, it’s not enough for it to identify objects that it can see directly — it also needs the ability to infer the existence of objects that aren’t even visible at all.”
Reference: Firestone, C., & Little, P. C. (2021). Physically implied surfaces. Psychological Science. Advance online publication. https://doi.org/10.1177/0956797620939942
Adopted from the APS Podcast. see https://www.psychologicalscience.org/news/releases/2021-april-mimes-surfaces.html