Research Design Behavioral Pharmacology

Experimental Research Design Experimental control is essential in behavioral pharmacology research. –Independent Variables –Dependent Variables The type of experimental design may depends on the type of dependent variable being measured. –Within Subjects Designs –Between Subjects Designs

Experimental Design Importance of Placebo Controls –Placebo Effects Three-Groups Designs

Studying Drugs & Behavior Psychopharmacology –psychology + pharmacology OR OR –psychiatry + pharmacology Behavioral Pharmacology –behavior + pharmacology

Psychopharmacology OR Behavioral Pharmacology The distinction is not always clear. The term “psychopharmacology” was coined a few decades before the science of behavior analysis was developed. –Some people distinguish these specializations based on the accepted methodology to study drug effects. (i.e., a broader range of methods in psychopharmacology.) –Others distinguish them based on emphasis of research questions. –Others don’t distinguish them at all.

Behavioral Pharmacology A specialization of behavioral science that applies the methods and concepts of behavior analysis to explain the behavioral effects of drugs. –Behavior Analysis is a unique natural science approach to study behavior and a philosophy of science that was popularized by B.F. Skinner.

Science of Behavior Analysis Environmental events are emphasized because: –such variables clearly influence behavior –they are directly observable –we have the technology to study them –they are subject to direct manipulation

Behavior Analysis a natural science emphasizing effects of environmental variables on behavior concerned with behavior in its own right, not as an indication of events at another level of analysis a proven practical approach to deal with a wide variety of behavioral problems (including drug use and abuse)

Behaviorism in the Early 20 th Century Ivan Pavlov –Respondent conditioning –Some of Pavlov’s early work examined drug effects on respondent conditioning. –This work preceded the formal development of Behavioral Pharmacology. John Watson –Introduced Behaviorism –First to put forth a strong natural science approach for psychology –Attempted to explain behavior primarily in terms of respondent conditioning –Methodological Behaviorism (deals only with publicly observable events)

Radical Behaviorism Philosophical Position Adopted and Promoted by B.F. Skinner –conceptualizes behavior as involving both public and private events –assigns no special status to private events –Private events (e.g., thoughts, feelings) do not cause overt behavior: they are stimuli that function similar to directly observable stimuli they are difficult to study

Experimental Analysis of Behavior Essential features of EAB Research JEAB (founded in 1958) continues to be an important outlet for EAB research

Uses of EAB in Behavioral Pharmacology Main Assumptions –Behavior is important in its own right. –An intensive study of a few subjects is a fruitful research strategy. –Graphic analysis of data is desirable. –Direct and repeated measures are invaluable. –Variable data are best dealt with by isolating and controlling responsible extraneous variables. –Studies of nonhuman subjects under controlled experimental conditions can be of great value to understand variables that control human behavior.

Historical Landmarks in Behavioral Pharmacology

Research Areas in Behavioral Pharmacology Behavioral Loci –what aspects of behavior are altered by the drug (e.g., reaction time) Behavioral Mechanisms of Action –the stimulus functions of the drug; the effects of the drug on the capacity of other stimuli to control behavior Variables that Modulate Drug’s Behavioral Effects –e.g., other stimuli, alternative reinforcers etc…

Measuring Psychoactive Drug Effects on Behavior Levels of Arousal –EEG activity and Sleep –Arousal and Mood States –Arousal and Activity

Measuring Performance in Humans Perception –Psychophysical measures of threshold absolute and differential thresholds critical frequency at fusion test Cognitive Performance and Intellectual Functioning –vigilance, attention, learning & memory tasks mental arithmetic digit symbol substitution test Motor Performance –reaction time, hand-eye coordination e.g. pursuit rotor test

Measuring Behavior in Nonhumans Unconditioned Behavior –Spontaneous motor activity measured in an open field apparatus –Stereotypic behaviors

Measuring Behavior in Nonhumans Respondent Conditioning –Conditioned Place Preference –Conditioned Taste Aversion

Measuring Behavior in Nonhumans Operant Conditioning –emphasis on antecedents, responses, consequences, and contingencies of reinforcement –the process of modifying some characteristic of behavior by altering its consequences

Schedules of Reinforcement Ratio Schedules vs. Interval Schedules –Some drugs have been shown to exhibit “rate dependency” –e.g., Stimulants increase responding under FI schedules but suppress responding under FR schedules Escape-Avoidance Tasks –Some drugs (e.g., anxiolytics) block avoidance behavior without affecting escape behavior. Punishment Schedules –Responding maintained by appetitive rewards (e.g., food) may be suppressed by punishing stimuli (e.g., electric shocks). –Some drugs increase behavior that has been suppressed by punishment (e.g., CNS depressants)

Other Common Operant Procedures in Behavioral Pharmacology Drug Discrimination –analyzing drugs according to their stimulus properties –tool for classifying novel drugs –determining neurochemical mechanisms of drug action Drug Self-Administration –analyzing drugs for reinforcing properties –common model to assess abuse liability