Experimental Investigation of Drug Effects (Ch2)

Question 1

Independent variable

Answer 1

Manipulated variable (drug dose), range from low to high to produce a DRC

Question 2

Dependent variable

Answer 2

measure of behaviour of the subject (drug effect)

Question 3

Within-subject design

Answer 3

Subject serves as their own control (eliminate individual difference variation). Use with stable behaviour, compare behaviour under drug to not under the drug. All individuals experience all experimental conditions. Fewer participants, longer to run, know effect in each individual.

Question 4

Between-subject design

Answer 4

dependent mesure not stable across days or to compare different doses/drugs. Randomly assign rats to different hours, each group exposed to a different experimental condition and compare groups. Faster, need many more participants, compare average effects between group (don’t know what effect is on each individual)

Question 5

Experimental control

Answer 5

control condition: eliminate method of administration as a source of behaviour change. Make a similar as possible to the drug condition, but no drug. Injection of saline, or sugar pill

Question 6

Placebo effect

Answer 6

pharmacological inert compound administered to an individual. If a person believes they are getting a drug effect (side effect), they frequently report experiencing the effects. Expectation of an effect must be discriminated from the dug effect. Essential aspect of experimental design with humans.

Question 7

Experimenter bias and how to solve issue

Answer 7

Experimenter may unknowingly influence the results if they know who has been given a placebo and who has been given a drug. Double-blind procedure: neither the subject nor the researchers know who has been given a drug and who has been given a placebo.

Question 8

Non-experimental research

Answer 8

Correlation, not causation. Nonexperimental research measures 2 variables and uses statistics to see if there is a relationship between variance in one variable and variance in the other (correlation)

Question 9

SMA (spontaneous motor activity)

Answer 9

place the animal in an open field box and count the number of line crossings within a fixer period of time. The alternative is to use a grid of IR beams.

Question 10

Stereotopy

Answer 10

repetitive movements in a vertical dimension

Question 11

Ambulatory movements

Answer 11

horizontal movements

Question 12

Respondent (Classical/pavlovian) conditioning

Answer 12

The UCS causes a UCR. The CS and the UCS are paired and and UCR happens. Eventually, the CS causes the UCR(CR). The CR (heart rate, salivation, drug effect)

Question 13

Operant behaviour

Answer 13

voluntary, emitted behaviour. Consequences influence the probability of occurrence of behaviour. Reinforcement strengthens and punishment weakens the behaviour.

Question 14

Schedules of reinforcement

Answer 14

Different schedules produce different patterns of motivated behaviour.

Question 15

Rate dependency

Answer 15

the effect of a drug behaviour depends on the rate of occurrence of the behaviour under baseline (no drug) conditions.

Question 16

Test stimulus properties of drug

Answer 16

self-report paradigm: the animal indicates how it feels (levers - press one to inject drug and the other to inject saline. If presented with 2 drugs, can tell preference between them)

Question 17

Tests of abuse potential (3)

Answer 17

1) Rate of responding
2) Progressive ratio
3) choice

Question 18

Rate of responding

Answer 18

larger reinforcers produce higher rates of responding.

Question 19

Complications with using rate of responding

Answer 19

the duration of action (short acting drugs self-administered at higher rates than long-acting), drugs interfere with the ability to make a response (pentobarbital puts you to sleep)

Question 20

Progressive ratio

Answer 20

schedule of reinforcement where response requirement (# lever presses (price)) to obtain a reinforcer increases with each successive reinforcer. The breakpoint is the value that is above the drug.

Question 21

Choice (2 tests)

Answer 21

The operant chamber with 2 levers, associate a drug to each and test for preference. The animal will show a preference for the drug that is more reinforcing.

Conditioned place preference/aversion - inject animal with drug in one context and saline in another context. Let the animal move freely between each, and if drug experience is positive, animal will spend more time in drug context (CPP)

Question 22

Tests for antipsychotic effects (1)

Answer 22

1) escape-avoidance task

Question 23

Escape-avoidance task

Answer 23

light on for 30s and then a 10s shock occurs. The animal can press the lever during the 30s to make shock not happen or press lever during the shock to stop it. Antipsychotics interfere with avoidance .

Question 24

Tests for anxiolytic effects (2)

Answer 24

1) light-dark crossing test
2) elevated plus maze

Question 25

Light-dark crossing test

Answer 25

2 compartment box, one side is brightly lit and the other is dark. The animal is placed in the bright side and the number of crossings is recorded. The time spent in the bright side and total motor activity are measured. Anxiolytics increase these measurements (rats freeze when anxious)

Question 26

Elevated plus maze

Answer 26

cross shaped, 2 open and 2 closed arms. Elevated. If anxious, spend less time on open arms. Measure time on open arms, anxiolytics increase these measurements

Question 27

Tests of analgesic effects (pain relief) (2)

Answer 27

1) tail flick test
2) hot plate test

Question 28

Tail flick test

Answer 28

beam of light project onto an ink blackened spot on a rat’s tail (absorbs light more) measure interval between beam onset and removal of tail. Analgesic increases latency.

Question 29

Hot plate test

Answer 29

metal plate at 50 degrees, initial response is to raise and lick hind paw. Measure interval to paw lick, kicking or attempt to escape apparatus. Analgesic increases latency.

Question 30

Tests of learning and memory (2)

Answer 30

1) Mazes (radial arm maze)
2) delayed matching to sample

Question 31

Mazes

Answer 31

Radial arm maze:
- multiple arms from a central point. Food at end of each. Error: visit an arm more than once. Different variations: bait 1/2 of arms, use cues within (intramaze) or without (extra maze) with a spatial relation to the baited arms.

Question 32

delayed matching to sample

Answer 32

present a sample stimulus. Delay. Present 2 stimuli (one is the stimulus already seen). Matching to sample task: reinforcement if choose stimulus previously seen. Non-matching to sample task reinforcement if chooses stimulus not previously seen.

Question 33

Testing in humans

Answer 33

subjective effect (introspection to generate a testable hypothesis), rating scales (profile of mood states).

Question 34

Perception: absolute threshold and difference threshold

Answer 34

absolute threshold: lowest level of stimulation that can be reliable detected

difference threshold: smallest unit of difference in stimulation that can be reliably detected (JND, just noticeable difference).

Question 35

difference threshold - critical frequency of fusion

Answer 35

CFF (critical frequency of fusion): frequency at which a flickering light appears to be constantly illuminated.

Question 36

Tests of motor activity (3)

Answer 36

1) reaction time
2) body sway (Romberg Sway Test)
- test ability to stand still without swaying
3) pursuit rotor
- hold the end of a stylus on a point on a rotating disk (hand-eye coordination)

Question 37

Test of attention and vigilance

Answer 37

Mackworth clock test: watch a circular dial with a moving clock hand. Hand occasionaly moves 2 steps rather than 1. Push button when this occurs

Question 38

Tests of memory in humans (short and long)

Answer 38

Short term memory:
- N-back test: presented a series of characters on a screen and who target character occurs, must report a character that occurred N back form the target.

Long term memory (explicit and implicit)
- free recall: presented with a list of terms, recall
- cued recall (recognition): resented with a list, shown an array of items, identify those that were on the list.