Experimental Psychology Extraneous Variables

Question

Directions: Identify any errors in the methodology especially in extraneous or confounding variables and failure to control them. Then, give solutions on how these mistakes should be corrected.

Situation: Leanne is experimenting to see if removing the hippocampus in rats' brains affects their memory. She first trains a group of rats to run a maze until they have all memorized their way through the maze. Then the rats are randomly split into two groups. Group A is placed under an operation wherein their brain hippocampi are removed. Group B is left alone. After Group A has been given enough time to recover, Leanne tests all the rats again with the same maze to see if they still remember their way through it.

Errors identified: ?

How to correct the errors: ?

Answer 1

Situation: Leanne is experimenting to see if removing the hippocampus in rats' brains affects their memory. She first trains a group of rats to run a maze until they have all memorized their way through the maze. Then the rats are randomly split into two groups. Group A is placed under an operation wherein their brain hippocampi are removed. Group B is left alone. After Group A has been given enough time to recover, Leanne tests all the rats again with the same maze to see if they still remember their way through it.

Errors identified: Were the rats randomly selected? Does the experimenter know which rats are in group A/B? Could the forgetting be due to the amount of time the "recovery" took (confounding variable), Could something else (lack of reward, etc...) be causing the rats to forget their way? (confounding/extraneous variable)

How to correct the errors: Random selection, Double-Blind Experiment, limit confounding/extraneous variables