This experiment is a replication of one of the most important experiments in the history of psychology. For decades, researchers thought the study of mental images was beyond the reach of science, and questioned their very existence. No one knew how to develop rigorous measures that could indicate mental images existed and explain how we use and manipulate them. The measures had to be clearly interpretable and repeatable by other researchers. Finally, Roger Shepherd, Lynn Cooper, and colleagues developed a methodology in which they rotated two images relative to each other and measured how long it took participants to determine if the images were the same or mirror images. The results provided both a rigorous and a replicable set of findings that allowed mental images to be examined for the first time in a scientific study.
References:
Cooper, L. (1975). Mental rotation of random two-dimensional shapes. Cognitive Psychology, 7(1), 20-43.
Cooper, L. A. & Shepard, R. N. (1973). Chronometric studies of the rotation of mental images. In W.G. Chase (Ed.), Visual information processing (pp. 75-176). New York: Academic Press.
Metzler, J. & Shepard, R. N. (1974). Transformational studies of the internal representation of three-dimensional objects. In R L. Solso (Ed.), Theories of cognitive psychology: The Loyola symposium (pp.147-202). Potomac, MD: Lawrence Erlbaum.
1.2Experiment Setup
Figure 1.1
1.3Instructions
Instructions
You will need to press the space bar to begin the experiment. A fixation mark will then appear in the center of the screen. Please look at this mark. After a brief period, two images will appear, one on either side of the fixation mark. The two images will be the same or mirror images of each other. Your task is to decide, quickly and accurately, if these images are the same or mirror images. You may respond by clicking on the buttons below the images or using your keyboard.
Keyboard Responses
Key
What Response Means
F
same
J
mirror
1.4Experiment
Begin Experiment
Start Experiment
Figure 1.2
1.5Results
Results
Figure 1.3
1.6Quiz
Quiz
Question
1.1
One of the independent variables for this experiment is:
A.
B.
C.
D.
1
Incorrect.
Correct.
The independent variable is the value that is changed by the experimenter. In this case, the angle that the two images are rotated relative to each other is changed by the experimenter, so the correct answer is angle of rotation.
Question
1.2
One of the dependent variables in this experiment is:
A.
B.
C.
D.
1
Correct.
Incorrect.
The dependent variable is the value that the experimenter collects to indicate how you performed in the experiment. In this case, the most important variable we measured was how fast you responded to the images displayed, so the correct answer is reaction time.
Question
1.3
One of the discoverers of this phenomenon is:
A.
B.
C.
D.
1
Correct.
Incorrect.
Although the others are very important cognitive psychologists, the correct answer is Roger Shepherd.
Question
1.4
What statement below best describes the results found in this experiment?
A.
B.
C.
D.
1
Correct.
Incorrect.
What was interesting about the results of this experiment was the finding that as the angle between the two images increases, reaction time increases linearly.
Question
1.5
The results of this experiment suggest that:
A.
B.
C.
D.
1
Correct.
Incorrect.
As the angle between the two images increases, reaction time increases linearly, just as if we were rotating a real object. This finding suggests that mental images exist, and we can manipulate them like real world objects.