In one well-known study on empathy, participants were required to watch a confederate ("elaine") receive electric shocks. they were told either that they had to watch her receive 10 full trials of shocks, or that they could leave after watching the first two trials only. they were also told that their values and interests were similar to elaine's (similarity group), or that their values and interests were different from elaine's (non-similarity group). after the first two trials were completed, participants were told that elaine was unusually upset by the shocks due to a negative childhood experience related to electricity. participants were asked whether they would be willing to switch places with elaine. in this study, the 10-trial versus two-trial instruction was designed as a manipulation of and the similar versus dissimilar information was designed to be a manipulation of