PS 515 Unit 4 Assignment 2: Learning and Behavior

PS-515-01: Learning and Behavior

Unit 4 Assignment 2


Unit 4 Assignment 2

For this assignment we are to complete exercises 22, 23, and 25 of the Sniffy the virtual rat. We are to get Sniffy trained so that he can associate the sound with food. Sniffy will press the bar in the chamber before he is even trained to do it. Therefore, when he is conditioned to press the bar, he is not being taught to do something that he is incapable of doing. The food will be the reinforcement and his frequency of which bar he is to press will increase (Alloway, Wilson, & Graham, 2011).

Exercise 22: In this exercise Sniffy was trained to recognize the sound of the lever as it dispenses food. This exercise lasted around 17-20 minutes. This was known as magazine training which is a method that involves using what amounts to a classical conditioning procedure to turn a neutral stimulus into a secondary reinforcer. Within the first few minuets Sniffy explored the cage. When he would get close to the hopper the rate of the reinforcement was increased. Sniffy started to press the bar on his own after he developed a 50% association between the sound and reinforcement. Sniffy was reinforced almost immediately after receiving the previous reinforcement. This stopped him from straying away from the food hopper, and the rate of association acquisition was increased (Alloway, et al., 2011).

Exercise 23: Once the operant chamber was programmed to drop a pellet of food into the tray whenever Sniffy pressed the bar, his occasional spontaneous bar presses will be effectively reinforced. It took about 50 minuets to complete this exercise, and Sniffy was shaped into pressing the bar behavior. Shaping is the name for a method used to train an animal to do something by using reinforcements. Reinforcements are used to for progress but then withheld until more progress is made (Alloway, et al., 2011). Both positive and negative reinforcements were used.

Exercise 25: Extinction is the term for the behavior changes that happen when a previously reinforced behavior is no longer producing reinforcement (Alloway, et al., 2011). The main reinforced which is food and the secondary reinforcer which is the magazine sound are turned off. This is known as the standard extinction procedure. At the start of this exercise every time Sniffy pressed the lever there was no food. Sniffy had a extinction burst. In the beginning Sniffy would press the lever several times in a row and sniff for the food and he would continue to press the lever. Once he realized that there was no food being produced, he stopped pressing the lever, and this took around 15-20 minutes. He pressed the lever around 80-85 times to stop the response without the reinforcement.


Alloway, T., Wilson, G., & Graham, J. (2011). Sniffy the virtual rat: Pro version 3.0.

(3rd ed). Boston, MA: Cengage Learning.