Week 3 - Research Methods in Behavioural Pharmacology

Question 1

What is a between-subjects design?

Answer 1

• Experiments conducted with 2 (or more) different groups
o IV operationalized as different groups
• Usually interested in the difference between the means of these groups

Question 2

What are the advantages of a BS Design?

Answer 2

• Easier and more time efficient to run

* Allows observation of variables that are not stable (i.e. habituation, practice effects)

Question 3

What are the disadvantages of BS design?

Answer 3

• Many variables are unable to be controlled (e.g. systematic differences between the groups_)
o Need more participants so these effects average out
• Results are presented in terms of group differences; masks change within the individual
• Method of allocating to groups (randomized controlled trial; consecutive case design?)

Question 4

What is a within subjects design (repeated measures)?

Answer 4

• Same participant involved in every level of the experiment
o IV is operationalized as different levels/testing occasions that all participant receive

Question 5

What are the advantages of a WS design?

Answer 5

• Requires fewer participants

* Each participants acts as their own control

Question 6

What are the disadvantages of a WS design?

Answer 6

• Not amenable to measurement of unstable variables
• Time and money
• May need alternate forms to assess DV to counteract practice effects
• May need to counteract cross-over effects

Question 7

What are control groups, and what are they used for?

Answer 7

• Used to ensure the effect observed is due to the variable we manipulated and not some other variable
• Especially important in between-subjects designs
• A control group will be identical to the groups being tested, except for the manipulation

Question 8

What is a placebo and what are they useful for?

Answer 8

• A placebo control conditions similar to experimental condition, except rather than receiving the drug (or no drug) they receive a substance containing no active ingredients (a placebo)
• Placebo controls are extremely useful for investigating whether any benefits derived from a drug are due to placebo effects

Question 9

What is the Nocebo Effect?

Answer 9

if the side effects told to be negative then can start to actually experience them

Question 10

What is the expectation mechanism hypothesis?

Answer 10

hypothesized that you need the priming of pain reduction to actually experience pain reduction

Question 11

What is a three groups design?

Answer 11

1. Given a new drug
2. Given a proven drug
3. Given a placebo

Question 12

What does a three groups design allow?

Answer 12

• allows a comparison between new drug and placebo
• allows comparison between new and established drugs
• allows experimenter to see if measures are sensitive enough to detect change (i.e. compare proven drug and placebo)

Question 13

What are alternative combinations of groups used to answer questions of?

Answer 13

o Effectiveness of drugs vs. non-pharmacological interventions
 E.g. CBT group vs. drug-treated and placebo-groups
o Specificity of drug effects:
 E.g. include groups comprising people with different mental illnesses
• Does the drug work in depression exclusively?

Question 14

How else may effects be assessed?

Answer 14

over time (multiple measurements (longitudinal design) or once-off (cross-sectional design)) 
Sources of Bias

Question 15

What are some sources of bias

Answer 15

o	Experimenter and participants expectations/bias (double blind studies) 
o	Selection bias: experimental controls 
	Demographic differences (age/gender) 
	Cultural differences 
	Personality differences 
	Education ect

Question 16

What is the level of control for experimental designs from low to high?

Answer 16

Introspection -> Naturalistic Observation -> Case History -> Survey -> Test -> Correlation -> Experiment

Question 17

What are potential variables?

Answer 17

• Depending on the drug and its action, some of the domains in which we may look for effects are:
o Arousal
o Cognition
o Perception
o Motor function
o Mood
• We might also want to measure side effects/biochemical or physiological drug effects

Question 18

What is the outcome of more performance measures?

Answer 18

• The more measures we use:
o The more comprehensive our assessment
o The more costly our experiment (financial and time)
o The greater the need to consider experimental controls and logistics (e.g. order we administer measures)

Question 19

What does assessing change in performance across domains tell us?

Answer 19

tells us something about how the drug works, and the effects it produces (primary and side effects)

Question 20

What are the levels of arousal from low to high?

Answer 20

Death -> Coma -> Sleep -> Drowsy -> Normal -> Aroused -> Highly excited -> mania -> convulsions -> death

Question 21

What is one brain scanning way to measure arousal?

Answer 21

• EEG: a measure of arousal/detects potential differences between points on the scalp and neutral points on the body

Question 22

What are other ways to measure arousal?

Answer 22

o Introspection?
 Unstructured introspection
 Systemic introspection
o Ask an observer?

Question 23

How to measure mood?

Answer 23

• Can be studies experimentally (e.g. we can test drug effect by inducing mood states) or using a b-g design (e.g. depressed vs. non-depressed patients)
• Measurement could be by self-report, doctor’s assessment, informant report, questionnaire, tests of biological markers of depression etc.
o Consider the adv and dis of these ways of assessing drug effects on mood

Question 24

What does perception research study?

Answer 24

• Perception research often investigates the changes in the sensitivity of a person’s perception brought about by changes in the internal or external environment (e.g. drug use)
• Changes in sensitivity = thresholds (two types)

Question 25

What are the two types of thresholds

Answer 25

Absolute and difference thresholds

Question 26

What is critical frequency at fusion (CFF)

Answer 26

The sensitivity to drug effects

Question 27

What is cognitive performance?

Answer 27

• Ability to process, store and retrieve information (e.g. attention, memory, learning etc); can also include higher-level processes such as planning, set-shifting and response inhibition

Question 28

How is this manipulated experimentally?

Answer 28

o Effect of drug at different stages of cognitive process can be assessed (e.g. may affect storage of information, or earlier attention processes)

Question 29

How to measure motor performance?

Answer 29

simple or choice reaction time, tapping, pursuit rotor, ect.

Question 30

What are the methods to study side effects/physiological effects?

Answer 30

o Questionnaire (e.g. yes/no questions; rating scale etc)
o Biochemical assay
o Doctor’s check-up/physical examination
o Informant report
 Strengths and weakness
• Some methods of assessing physiological effects: biochemical assays, MRI scans, PET scans

Question 31

What are factors to be considered in drug studies?

Answer 31

o Wash out effects (esp. in w/g designs)
o Deprivation of drug administered
o Dose of drug used (e.g. P. compliance with instruction)
o Inclusion of biochemical assays
o Controls for routine/habitual or other drug use
o Non-specific treatment effects
o Special group selection factors (mild, moderate, and severe depression?)
o Time frame for assessing effect
o Reporting of adverse events/non-compliance/attrition

Question 32

What are some major considerations in drug development?

Answer 32

1. Medical need
2. Commercial potential
3. Feasibility for mass production
   • “Orphan drugs”

Question 33

What are the 4 stages for FDA approval?

Answer 33

1. Preclinical investigations (basic science; tests on cells & animals; effects of drugs noted for side effects ,toxic effects, addiction, cancerous tumors, fetal deformities, pharmacodynamics)
2. Clinical investigation (human testing, 4 phases, incl. 3 phases of clinical trials)
3. Review of NDA (New Drug Application)
4. Post marketing studies

Question 34

What is step 1 of animal testing in drug development?

Answer 34

Step 1: Determining toxicity
• Acute toxicity (for single doses)
• Sub acute toxicity (short term use of drug)
• Chronic toxicity (longer-term drug use)
• Special toxicity (carcinogenic? Taratogenic?)

Question 35

What is step two of animal testing in drug development?

Answer 35

Direct and indirect pharmacological studies?

Question 36

What are direction pharmacological studies?

Answer 36

o To locate direct measures of changes induced by drugs via tools such as:
 Rating scales. Objective measures (e.g. jiggle-case/tail suspension test), conditioning studies, sites of action studies

Question 37

What are indirect pharmacological studies?

Answer 37

o To identify markers or signs of effects rather than evidence of the effect itself or
o To observe effects on behaviors that are induced in animals

Question 38

How is conditioned behaviour measured in nonhumans?

Answer 38

• Schedules of Reinforcement: patterns that determines when reinforcement are to to be given

Question 39

What are the different types of schedules and their subgroups?

Answer 39

o	Ratio Schedules 
	Fixed ratio (FR) 
	Variable ratio (VR) 
o	Interval Schedules 
	Fixed Interval (FI) 
	Variable Interval (VI)

Question 40

What is the stimulus property of a drug?

Answer 40

 Ability to act as a discriminate stimulus in a discrimination learning task

Question 41

What are the processes for determining the reinforcing properties of drugs?

Answer 41

o Rate of Responding
o Progressive Ratio
 Breaking point (organism will stop responding)
o Choice
 2 levers; one has consequences. Exposure to 2 drugs over separate sessions; then observe animals’ choice of drug A or B
o Conditioned place Preference
 Animal will spend time in area of reinforcement

Question 42

What are the stages for clinical investigation (human volunteers?

Answer 42

o Phase 1: human testing to determine toxicity and side effects in healthy human (paid) volunteers
o ‘Phase 2: human testing in clinical samples (i.e. patient groups) to assess potential therapeutic effects (+adverse)
o Phase 3: expanded clinical trials using basic 3-group design
o > approval or rejection of new drug for licensing and marketing
o Phase 4: accumulation of data on drug effects