Contrast effects with a shift in work load

TLDR: In this paper, both positive and negative contrast effects resulted from switching lever counterweights from heavy to light and light to heavy in a standard bar-pressing situation, and the results were interpreted as supporting a relative position concerning perception.

Abstract: Both positive and negative contrast effects resulted from switching lever counterweights from heavy to light and light to heavy in a standard bar-pressing situation. Ss under the above two conditions were compared to control groups which continued with either heavy or light counterweights througfiout the study. Differences between postshift performance and the controls were significant (p <.01), but they did not persist in extinction. Tlie results were interpreted as supporting a relative position concerning perception.