Humans can recognize an action like biting regardless of whether they see a man eating a sandwich or a dog gnawing on a bone. But what in the brain helps to explain the innate similarities of the two, and does this reasoning change depending on the visual cues?

Those are the questions Alon Hafri, Russell Epstein, and John Trueswell of the Department of Psychology in the School of Arts & Sciences set out to answer.

Their research confirmed previous findings, which showed that parts of the brain within the inferior parietal, occipitotemporal, and premotor cortex are vital for recognizing actions. But more importantly, they discovered that how human beings understand these actions doesn’t change irrespective of whether they happen in a photo or video. The researchers published their findings in The Journal of Neuroscience.

“This is one of the essential aspects of perceiving the visual world: understanding not just what’s there, but what’s going on,” says Epstein, a psychology professor. The work goes a step beyond comprehending how the brain recognizes objects and scenes, previously an area of focus for Epstein’s lab.

For this research, the trio picked a set of eight simple actions, and then made two separate stimulus sets.

“We created a dynamic set, the video format. These are carefully controlled, the same two actors from the same viewpoint, in the same setting, performing these actions,” says Hafri, a fourth-year graduate student. “We also created a static set, the image format. Here there is no motion and there is huge variety in terms of what they look like, what objects and viewpoints you see, and in what setting.”

Because of how the two differ, any commonalities must relate to the action itself, Hafri adds. In other words, in dynamic and static depictions of hair brushing, the only similarity is what is happening—the action.

Hafri and colleagues then showed 15 college-age adults several sets of these videos and photos in five-minute increments, while scanning them with fMRI and having them perform an unrelated task to keep them engaged.

“For every image and every video, we have [data on] how their brains responded during viewing,” Hafri says. “An individual’s pattern of brain activity when he or she observes actions is surprisingly consistent no matter how different these actions, like biting, look in the world.”

Next up, the researchers will try to determine whether reading a sentence about an action—for example, “Jim pushes Joe”—leads to the same result as viewing a picture or video of that very thing. It’s all in the name of seeing life more clearly.