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).
. By giving one a motor set (to respond-“get ready to grab it”), which is faster than a sensory
set (to observe-“watch for it to drop”).
. By letting one subject but not the other, see you “prepare” to release the stimulus.
7. Using any of the above (or in combination), your hypothesis will again be “proven”. Have the
students list the biases in this test. Repeat, using more subtle differences each time.
DISCUSSION
The discussion should lead to the notion of relevant versus irrelevant variables in an experimental
situation. Relevant variables are those likely to affect the dependent measure (reaction time), such as those
used to bias this experiment. Irrelevant variables are those unlikely to affect the results, such as, in this case,
barometric pressure, hair color, socioeconomic level, etc. This should lead to discussion of the need for
experimental control procedures in order to identify and control relevant variables so that both
experimental conditions are the same in every regard except the independent variable. Then, any differences
in results can be attributed to the independent variable.
ADDITIONAL RESOURCES
Stanovich, K.E. (1992). How to Think Straight About Psychology. 3rd Ed. New York: Harper Collins.
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SALIVATING FOR PAVLOV
OBJECTIVES
1. To have students personally experience what it means to be conditioned to elicit a classical salivary
response.
2. To perform a simple but effective demonstration of Pavlovian conditioning on the entire class.
3. To collect conditioned response data on acquisition and extinction that will provide the impetus for
discussing applications and extensions of conditioning principles in everyday life.
OVERVIEW
Many students find the usual discussion of Pavlov’s discovery of the principles of conditioning
uninteresting and without any personal relevance. Having them salivate–as did Pavlov’s experimental
dogs–may ring a bell for them!
1. Do not begin by stating the principles of conditioning, but request that the students read Psychology
and Life, chapter 9 before this demonstration.
2. Do assess the students’ knowledge of the meaning of US-UR, CS-CR; acquisition and extinction.
3. Perform the following demonstration, which was developed by Dennis and Rosemary Cogan
(Texas Tech University) and described in detail in their article in Teaching of Psychology, 1984, Vol.
11, pp. 170-171.
GENERAL INTRODUCTION
Although conditioning represents one of the most important discoveries in psychology, students fail to
appreciate its significance. In part, this is due to the description in terms of dogs salivating to bells, hardly
of apparent personal relevance to students. By making the students salivate to an arbitrary signal (CS) –the
name “Pavlov” –they will be in a better position to appreciate how virtually any neutral stimulus can come
to have the power to elicit powerful biological responses.
Following the demonstration, you should be sure that the class understands the significance of the research
on conditioning of drug responses–and lethal overdoses–as one “real-world” consequence.
PROCEDURE
Materials
. One can of sweetened lemonade powder (such as Minute Maid).
. Small paper cups, one per student, of the kind used for ketchup and mustard in some cafeterias.
. Pour enough of the lemonade powder in each cup so that a student can taste some on each of about
70 conditioning trials. (Try it first yourself to determine the approximate amount.)
Method
1. Tell students to moisten the tip of the index finger of their preferred hand and watch for the
instructor to signal them to “Dip.”
2. At the visual cue of the instructor pointing down, students dip their moistened fingers in the
lemonade powder and put a small amount of it on their tongues.
3. The CS is the spoken name “Pavlov” said between (0.5 and 1.5 seconds) prior to the “Dip” signal.
4. These conditioning trials are spaced at intervals of 10 to 15 seconds.
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5. Test trials are given after 8 to 12 conditioning trials. In a test trial, instead of the “Dip” signal, the
instructor holds up a card with the word “Experience?”