Ms. Jingles and Fixed Ratio Reinforcement

     After Ms. Jingles was shaped to press the bar on her own, we put on her an FR (Fixed Ratio) schedule of reinforcement. We started with FR-2, which meant she would have to press the bar twice to get the reinforcement (the food pellet). The highest schedule Ms. Jingles was able to attain was FR-12. I'm still very impressed that she was able to learn to press the bar 12 times in order to get a single reinforcement. During the FR-12 training session she pressed the bar a total of 482 times in 21 minutes for 41 reinforcements. It was apparent she was learning to press the bar 12 times because after a series of presses, she was check the hopper. If there were no food pellets in the hopper, she would return to the bar and continue to press it until she heard the sound of the food magazine. There were also several instances where she pressed the bar 12 times in a row without stopping to check the hopper.

     One major change I noticed in Ms. Jingles behavior while moving from lower FR schedules to higher FR schedules was her focus on the bar. When she only had to press the bar two or three times to get a reward, she would spend a large portion of the training session moving about the cage rather than pressing the bar. However, with higher FR schedules, such as FR-12, Ms. Jingles stayed around the bar much more than with lower FR schedules.

This is a short video of Ms. Jingles during the FR-12 training session.