Frank Durgin and Zhi Li's Work on Slope Perception Featured in ScienceNOW

Majandra Rodriguez Acha '12

Frank Durgin and Zhi Li's Work on Slope
Perception Featured in ScienceNOW

by Majandra Rodriguez Acha '12
12/8/2009

Frank Durgin
Frank Durgin at work in the lab with a student

Swarthmore's Crum Woods are not only a site for joggers, dog walkers, and impromptu hikers - they can also be a location for scientific discovery. Professor of Psychology Frank Durgin and research associate Zhi Li's findings on steep slope perception, born out of a walk in the Crum and later published in the Journal of Vision, were recently featured in Science magazine's ScienceNOW.

When approaching a steep bank on the side of Crum Creek, Durgin and Li came to the realization that steep slopes appear less steep the closer one gets to the ledge. They then tested this finding through numerous laboratory experiments in which students estimated the angle of a slope at different distances from the slope. These experiments also involved the creation of a virtual environment in which participants were placed on top of a hill and then asked to guess the slope's angle as they came closer to the edge.

Durgin and Li found that students were consistently more accurate in their angle estimations the closer they came to the edge; when they were farther away, they tended to overestimate how steep the slope was. This is "surprising", as psychologist Bruce Bridgeman of the University of California, Santa Cruz states in the ScienceNOW article, for Durgin and Li's finding goes against the "danger hypothesis." This hypothesis predicts that we ought to exaggerate a dangerous slope the closer we get to it. Nonetheless, as Durgin and Li realized on their walk in the Crum, our actual perception performs in the opposite way.

Frank Durgin specializes in human perception and cognition and directs the Psychology Department's Perception Laboratory.