An experiment by Darley and Batson (1973) gave the following results:

‘As demonstrated by earlier studies by Darley and Batson (1973), a situation that can effectively hinder the experience of empathy for our fellow man is being in a rush. An ingenious experimental setting was put into place where presumed powerful determinants, such as education, professional commitment to helping and an awareness of ethics were juxtaposed against the seemingly mundane factor of time pressure. In the experiment, priest seminar students encountered a man slumped in an alleyway coughing and in apparent need for help. The only aspect that was varied for 16 different subjects was the amount of hurry they were said to be in. The participants were on their way to a discussion with their professors (a few were even getting ready to talk about the Good Samaritan Parable, a Bible verse about the importance of helping strangers in need) and some of the participants were told that they were already late to the meeting and had to hurry up if they were to make it. The surprising result was that time pressure overrode years of education on Christian ethics and a life long commitment to the curing of souls and caused the participants to rush by their fellow human in need, some of them even stepping over the victim in the doorway in order to get faster to the awaiting ethics discussion! It would seem that the lack of time made empathizing with the victim more difficult, even though the priest seminar students presumably had a dispositional tendency for caring about the needy.”

from Dennis T. Kahn, ‘Bystander intervention and norm shifting: A social psychological research overview’, downloaded from www.levandehistoria.se/files/bystander_social%20psychological%20research%20overview.pdf, p.16.

Darley and Batson’s original research was published in:

Darley, J. M. & Batson, C. D. (1973). ‘From Jerusalem to Jericho: A study of Situational and Dispositional Variables in Helping Behavior’. Journal of Personality and Social Psychology, 27, 100-108. weblamp.princeton.edu/~psych/psychology/research/darley/