Extinction: Where did all the pellets go?

 

Bennie searches the pellet chute for a snack.

Pictured above is Bennie's first day of extinction. She responded to extinction in a fascinating way. Initially, she seemed confused by her lack of reinforcements. It did not take long for her interest in the lever to diminish. She would occasionally bite the lever, but mostly pawed at the pellet dispenser and try to climb up the chute. After getting bored of her pawing, Bennie wandered around the operant box and sniffed each corner for various amounts of time. There was even one moment where she jumped from the floor and attempted to touch something on the ceiling. At one point she stood with her hind legs on the lever and reached up toward the ceiling. I do not know why Bennie developed a fascination with the ceiling, but I assume it was out of boredom. When observing the graph, it may appear that Bennie went through an extinction burst. However, I am not sure if the spike in lever presses significantly differs from her normal responses on FR20. 

I witnessed the spontaneous recovery on day two of extinction. Around minute 25, Bennie began rapidly pressing the lever despite having no interest in it during the earlier session. The amount of excitement I felt when seeing spontaneous recovery was surprising. Bennie had gone ten minutes without pressing the lever. I did not expect her to press it for the rest of the session—so I was thrilled to witness such intense behavior appear out of nowhere.