Tall people are better than short people at gauging how far away they are from objects in the middle distance, a new study reports. The researchers say the results are evidence for the idea that people’s spatial perception abilities are influenced by their height, and develop over time.
The human brain depends on a certain model to provide “the best guess of where objects could be located,” said study co-author Teng Leng Ooi, a professor of optometry at The Ohio State University.
That model, or “intrinsic bias,” is typically revealed when people have very little information about where an object is located, e.g., literally in the dark, and must make an educated guess. People usually underestimate the distance between themselves and an object, and as objects get farther away, the effect gets larger. In the new study, 24 people were split into two groups of 12, based on their height. The average height (measured at the eyes) in the groups were 4 feet 11 inches (149.3 cm) and 5 feet 8 inches (173.4 cm). Over three experiments, objects were presented in different levels of light, with different amounts of information to help determine location. The people then guessed the distances to objects by a variety of means, such as pacing out the distance with their eyes closed, so the study was not dependent on the subjects’ sense of units of measure.
The results showed that the people in both tall and short groups showed the bias, increasingly misjudging the distance to far-away objects. However, the taller participants were more accurate in their guesses, and the difference in performance between groups was consistent across all conditions, the researchers said.