You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preshift Reward Magnitude and Positive Contrast in the Rat
Roger L. Mellgren, Jeffrey A. Seybert, Dan M. Wrather and Dennis G. Dyck
The American Journal of Psychology
Vol. 86, No. 2 (Jun., 1973), pp. 383-387
Published by: University of Illinois Press
Stable URL: http://www.jstor.org/stable/1421448
Page Count: 5
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
Four groups of rats were given 24 trials of training in a straight runway with 1, 2, 4, or 8 food pellets, and then shifted to 8 pellets. There was a 20-sec delay of reinforcement on each trial, to prevent a ceiling effect on running speeds. The three shifted groups showed stable positive contrast relative to the unshifted control group. Postshift running speed was inversely related to magnitude of preshift reward.
The American Journal of Psychology © 1973 University of Illinois Press