Feist−Feist: Theories of
Personality, Seventh
EditionV. Learning Theories 15. Skinner: Behavioral
Analysis© The McGraw−Hill^475
Companies, 2009reinforcers can change their value over time and in combination with other stimuli is
“yes,” and in this case nicotine can become even more reinforcing in the presence of
psychomotor stimulants.
How Personality Affects Conditioning
If conditioning can affect personality, is the reverse also true? That is, can personal-
ity affect conditioning? Several thousand studies with both animals and humans have
demonstrated the power that conditioning has to change behavior/personality. With
humans in particular, however, it is clear that different people respond differently to
the same reinforcers, and personality may provide an important clue about why this
may be so.
Returning to research on d-amphetamine and smoking, for example, there ap-
pears to be systematic individual differences on the effect; that is, it works for some
people but not others. Just as in the previous study, Stacey Sigmon and colleagues
(2003) studied the effects that d-amphetamine has on smoking using two different
reinforcers: cigarettes and money. In addition to trying to replicate the finding that
psychomotor stimulants specifically increase the reinforcing value of nicotine com-
pared to money, they wanted to examine whether there were any individual differ-
ences in the effect. If there were, then what might be some possible explanations?
Participants were adult smokers (averaging 20 cigarettes per day) between
the ages of 18 and 45, with a mean age of 21; 78% were European American and
61% were female. To be included in the study, participants had to test negative for
drugs other than nicotine and report no psychiatric problems, and women had to
practice a medically acceptable form of birth control and test negative for preg-
nancy. Participants were informed that they could receive various drugs, including
placebos, stimulants, and sedatives, and that the purpose of the study was to in-
vestigate the effects of these drugs on mood, behavior, and physiology. Participants
were paid $435 if they completed all nine sessions.
The general procedure included nine sessions, the first of which was a 3.5-
hour session to acclimate the participants to the procedures and equipment; no
drugs were administered in the first sessions. Sessions 2 through 9 lasted 5 hours
each and included breath tests to ensure no prior smoking had occurred. Baseline
measures includedpre-session questionnaires and physiological measures such as
heart rate, skin temperature, and blood pressure. Also, each participant lit a cigarette
and smoked at least one puff in order to ensure equal time for all participants since
last exposure to nicotine. The experimental drug (or placebo) was then administered
followed by baseline mood questions and a light meal in order to prevent nausea.
Mood questions included “Do you feel any good effects?” “Do you feel high?” “Do
you feel nervous?” and so forth. Using a double-blind procedure, participants re-
ceived either a placebo or d-amphetamine. The participant then completed a multiple-
choice test that pitted money against smoking to assess baseline levels of the
monetary value of smoking. For example, the participant was given a series of 45
hypothetical choices between smoking and a progressive amount of money. The point
at which the participant stopped choosing smoking and chose money was referred to
as the “crossover point” and was considered an index of drug-reinforcement efficacy.
Chapter 15 Skinner: Behavioral Analysis 469