Week 2 : Behavioural Analysis of Drug Effects Flashcards
How were the effects of drugs on behaviour studied initially?
Early accounts of the impact of drugs on behaviour were verbal descriptions or written accounts of subjective experience
e.g. Confessions of an English opium eater (first-person chronological account of progression of drug use from initial use to addiction).
e.g. Le Club Des Hachichins (group of wealthy intellectuals that used to take drugs and describe their experiences to each other).
What was the primary problem with early studies of the effect of drugs on behaviour?
Didn’t study their effects in a scientific/ rigorous manner. Instead relied on 1st person accounts/ subjective experiences which are not necessarily generalizable.
Jacques-Joseph Moreau
-Part of the “Club des Hachichins”
-Became interested in doing systematic analysis of the effect of marijuana on the central nervous system
-Using himself and others as test subjects, he documented his results in “Hashish and Mental Illness” in 1945
-He was the first doctor to publish on the effect of drugs on the CNS, and some of his work anticipated modern psychiatry
What are two things that Jacques-Joseph Moreau’s studies lacked?
-Modern chemical techniques for synthesizing the active chemicals in drugs
-Modern refinements in the study of behaviour
Wilhelm Wundt contribution to psychology
-From its establishment by Wilhelm Wundt in 1879, the science of psychology focused mostly on the subjective experience of an individual
-This is known as Introspection. The aim was to break down consciousness into its component parts in order to give an impression of the structure of subjective experience (‘Structuralism’)
e.g. the act of describe an apple in as much detail as possible gives the features that collectively make up someone’s impression of that apple (red, round, shiny etc.)
What came after introspection/ structuralism?
Behaviorist movement (1940s and 1950s)
Behaviorist movement (1940s and 1950s)
-John B. Watson felt that to be a science, psychology should study only observable behaviour, rather than subjective experience
-This way findings can be generalized to more people rather than just being a reflection of the processes happening in a particular individual.
-He and others (Skinner, Pavlov, Thorndike) laid the groundwork for a systematic study of behaviour in both humans and nonhumans
Early studies of behaviour
-Mostly carried out by pharmacologists.
-Involved unstructured observation of laboratory animals after they had been given a drug.
-Monitored degree of running, sleeping, convulsions, or other similar behaviours
-If the drug increased locomotor activity, it was taken to indicate it as a CNS stimulant
-If the drug decreased locomotor activity, it was taken as a CNS depressant
-Some psychologists also studied the effect of drugs on behaviour in mazes and runways
When did a separate discipline for the study of the effects of drugs on behaviour emerge? What caused this?
-The 1950s
-Two things contributed: Chlorpromazine, operant analysis of drug effects.
Chlorpromazine and the psychotherapeutic revolution
-In 1951 chlorpromazine was synthesized in France in the laboratories of Rhone-Poulenc by Paul Charpentier
-First thought of as a potentiator of general anaesthesia (extend length of anaesthesia effect).
-Produced a cooling of body temperature and disinterest without loss of consciousness
-Henri Laborit convinced some colleagues to try the drug on one of their psychiatric patients
-After 20 days of treatment, the man was ready to “resume normal life”
-This was huge as at this time such individuals were institutionalized for life (not any effective treatments available)
-Later in 1952, the drug was marketed as an antipsychotic drug (Thorazine)
-Many had interest in developing other drugs for psychiatric use i.e. Chlorpromazine’s discovery set off a revolution.
Due to Chlorpromazine (psychotherapeutic revolution) what became necessary?
Development of new drugs for wide spread psychiatric use required establishing behavioural techniques for drug screening i.e. needed to prove that the drugs were safe
Peter Drews
-Wanted to study the effects of drugs on behaviour
-Was unsatisfied with the current methods available to him (consisted mainly of just putting animals in a box with dose of given drug and seeing what happened—> not a lot of information provided through this technique).
-After meeting B.F. Skinner, he decided to study the effect of drugs on pigeons pecking for grain reinforcement in an operant chamber
-Published a series of seminal papers in the 1950s which are considered to be the first works of the field of behavioural pharmacology
Peter Drews Pigeon experiment
-1955 (considered some of the first studies in behavioural pharmacology).
-Studied the effect of drugs on pigeons pecking for grain reinforcement in an operant chamber (i.e. presented with light —> peck —-> get food).
-Trained pigeons on two different schedules of reinforcement
FR 50 – produces high rates of responding (ratio so reward dependant on response rate)
FI 15 min – produces low rates of responding (interval so reward dependant on time period and so pigeons not incentivized to peck)
-Gave pigeons pentobarbital (drug) in order to compare their behaviour in the operant chamber with and without the effects of the drug.
-The pattern of responding to the drug differs significantly across the schedules i.e. across the baseline behaviour
What is the most important idea that came from Dews (1955)
It depends on what the person or animal is doing when given the drug as to how it impacts on them
-hugely influential idea!!!
Joseph V. Brady
-Believed, unlike Skinner and his students (pure behaviorists only concerned with overt displays), that neuroscience could be useful in understanding the effect of drugs on behaviour
-Also believed that drugs and behavioural pharmacology research could tell us a lot about the function of the brain
-One of the first behavioural neuroscientists
Conducted important research on the relationship between stress and ulcers
Indicated that stress was a physical illness, an idea that became important to psychology and neuroscience (i.e. mental illness can be traced to a physical abnormality in the brain and is not a pure psychological effect).
-Great advocate for funding, urged pharmaceuticals and federal government to support research
What is the primary aim of studies in behavioural pharmacology? What is the independent variable? What is the dependant variable?
-Try to discover the relationship between the presence (or dose) of a drug and changes in behaviour
-Independent variable: what the researcher manipulates (drug or dose)
-Dependent variable-the outcome that is measured (some behavioural measure)
Experimental control
-Not enough to say what happened
-Must be able to say what would have happened without the drug
Within-subjects design
Compare behaviour in the presence and absence of the drug in the same individual
Between- subjects design
Compare behaviour in different groups (one drug, one control)
Placebo controls
-Always use a control condition that involves the administration of something to both groups
e.g. Sugar pill
e.g. Injection of saline
-Is a control for ‘expectancy effects’
Fillmore and Vogel-Sprott (1992)
-Studied the placebo effect
-Participants were given a cup of coffee and then tested on a psychomotor performance task
-Different groups were told that caffeine would improve or impair their performance
-Those told that caffeine would improve performance did best, those told caffeine would impair their performance did the worst, those told nothing about the effects of caffeine had middling performance.
-Important: No one got any caffeine so effects are purely based on expectations (i.e. demonstrating the placebo effect).
Balanced placebo design
-Developed in the mid 1970s. Still the gold standard for research with humans where expectation could influence results
4 groups (can be conceptualized as a table):
-Expect to get a drug, get a drug
-Expect to get a drug, get a placebo (any effect must be due to the expectation of the drug i.e. placebo).
-Don’t expect to get a drug, get a drug (any effect must be due to the drug)
-Don’t expect to get a drug, get a placebo
In other words covers all combinations in drug expectancy and taking
Three-groups design
-Used when a drug is undergoing clinical trials
3 groups:
-Experimental drug
-Placebo
-Established treatment drug
What is the purpose of including an established treatment drug in the three group design?
-Means that can determine whether the experimental drug is better i.e. is this drug doing to benefit individual above what is already provided by existing drugs.
Experimenter bias
-Can impact results as the experimenters knowledge/ behaviour can impact the subject’s behaviour (even without intention to do so)
-Usually both the experimenter and the subject don’t know the nature of the treatment. This is known as a Double-blind procedure.
Non experimental research
-Looks for a relationship between two measured events. In other words, no independently manipulated variable
-Can only look for correlations, can’t establish causality
-Example: Infants born to smoking mothers are more likely to die prematurely
-In the case of unethical experiments, we have to be satisfied with correlation
Unconditioned behaviour
-The simplest measure of behaviour in nonhumans: Spontaneous motor activity (SMA)
-How much behaviour is there? No learning is required just looking at the predisposed response and simply compare in the presence of drug and without.
Examples of unconditioned behaviour experiments…
-Open field: Give a mouse drug, how much do they run around
-Inclined plane test : mouse climbs up an inclined plane. How many times do they slip? Measures the effect that the drug is having on muscle tone and motor coordination.
