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Would it be possible
to introduce your suggestions for such change to the administration of your school or to those in
charge of the life-space unit in which you conducted your personal experiments?
5. Compare your reactions to those of other students who have done this exercise. What is the value of
experiential learning?
6. What are the psychological differences between being without sight versus being without hearing?
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Comparison of Anticipated & Actual Reactions to Being Blind for a
Day
Anticipated After Experience
Date: Date:
Time: Time:
Total Blind Time:
1. Most difficult motor skill or
response to make
2. Sense you will rely on most
3. How long it will take to adjust
to the situation to function
appropriately
4. What, if any, will be the
major problem or difficulty
in:
a) dressing
b) eating
c) attending class
d) engaging in a hobby or
favorite recreation
e) social relations
5. Sources of anxiety
6. Sources of gratification
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REACTION TIMES CAN BE REVEALING
OBJECTIVES
1. To sensitize students to the needs for experimental controls that help minimize experimenter bias.
2. To illustrate that without proper controls an experimental procedure can yield false conclusions.
3. To encourage students to design an experiment that answers the question, “Which sex has the
faster reaction time?”
4. To generate an operational definition of reaction time without the use of a clock.
5. To have some fun while demonstrating some important principles of research methodology.
OVERVIEW
The “experiment” is the most powerful analytical tool used in science. Cause-effect relationships can be
established only using well-controlled experiments. Psychologists employ this tool in the investigation of
virtually all aspects of behavior, including perception, learning, memory, cognition, motivation,
physiological processes, sensory processes, social behavior, development, and therapeutic procedures.
While the specific details of the methodology vary within each of these areas of investigation, the logic of
experimentation is essentially the same.
The following classroom demonstration and discussion should help elucidate the need for, and logic of,
experimental methods in the study of behavior.
GENERAL INTRODUCTION
You (the instructor) are to role-play as seriously as you can a biased-sexist orientation in the attempt to
confirm “what you already believe is true”; namely, that members of your sex are faster reactors than those
of the opposite sex. You will violate a series of experimental controls to prove your point. The class has to
catch you in the act.
PROCEDURE
Materials
Reaction-time device constructed from light cardboard (see template).
Instructions
1. Propose a hypothesis: “Males react faster than females” (if you are male), or “Females react faster
than males” (if you are female). This will usually draw protests from the hypothesized “slower”
sex.
2. Define reaction time: the time interval between stimulus presentation and a subject’s reaction.
Using our reaction time meter, it is converted into centimeters of distance between the signal
“Drop” and the subject’s reaction of stopping the falling reaction time meter.
3 . Select a student of the sex hypothesized as slower. Ask the student to come to the front of the room
and stand with his or her hand about even with the tip of the meter, with the thumb and forefinger
about two inches apart. Then, without explanation or warning, drop the meter between the
subject’s fingers. The subject will probably catch it. Record the reading, measuring from the top of
the thumb. Reaction time is measured in centimeters here rather than in seconds. Give only one
trial. Write the subject’s score on the board.
4. Then, ask for a volunteer of the opposite sex. Have this student come to the front of the room, sit
down, relax, and tell you his or her preferred hand. Then define the task: to stop the meter as soon
as possible when it is dropped after the signal “Drop” is given. Hold the meter so that the point is
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two inches above the student’s fingers (instead of even with them). Give the subject two practice
trials and a verbal warning signal of “Ready. ” Then give two test trials and record only the fastest
one. Then announce that the “obvious” conclusion has been confirmed.
5. At this point, the “losing sex” will protest, pointing out some of the biases you introduced. List
them:
. The first student was selected, while the other volunteered.
. The first student had to use cognitive processes (since the task wasn’t explained before the
trial); the second student used simple reaction time.
. The first student started with the point at fingertip level; the second started with it two
inches above the fingertips (leads to a discussion of accuracy of measurement).
. The first student had no “ready” signal; the second did.
. The first student was standing; the second was sitting.
. The first student had no practice; the second had practice trials.
6. Now pretend to run an unbiased test following the class suggestions. Eliminating all of the
previous biases (by essentially following the procedure for the second subject), you can still easily
bias the results:
. By having a fixed foreperiod (warning signal to stimulus onset) for one subject versus a
widely variable one for the other.
. By using different motivating instructions or feedback (“that wasn’t very good now, was
it?”
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