Prior fixed ratio training and durable persistence in rats

Following barpress training with different terminal fixed ratios (FR), rats were given the interpolated experiences of runway acquisition and extinction (as part of another experiment) followed by 2 months of vacation. Then they were tested in FR 10 barpress reacquisition, FR 10 barpress extinction, consistently reinforced runway reacquisition, and a second runway extinction. In a start (response initiation) measure, resistance to extinction during the FR 10 extinction and in the second runway extinction was positively related to the terminal FR values of the initial barpress training, an indication of highly durable differential persistence effects attributable to the initial training to different terminal fixed ratios of barpress responding.