Learning & Behavior

Front 1

Delay conditioning

Back 1

Conditioned stimulus presented before the unconditioned stimulus (forward pairing); most effective form of classical conditioning because it has predictive value and contiguity

Front 2

Trace conditioning

Back 2

Conditioned stimulus is presented long before the unconditioned stimulus (forward pairing); not as effective since it relies on the subject's trace memory of the conditioned stimulus

Front 3

Most important factors in classical conditioning

Back 3

1) Contiguity: how close the CS and US are temporally
2) Frequency of the pairing: increased pairings leads to a stronger connection between the CS and US
3) Predictive value of the CS

Front 4

Backward conditioning

Back 4

Unconditioned stimulus is presented before the conditioned stimulus; not effective because there is no predictive value

Front 5

Autoshaping

Back 5

In this experiment, the US will come irrespective of the animal's behavior, but when the US is paired with some signal (i.e., button that lights up), the animal will respond to this signal as if it is the US (i.e., pigeons will peck at a light as if it is food because it seems to signal food)

Front 6

Conditioned emotional response

Back 6

1) Train a rat to press a lever for food on a variable interval schedule so that the rat will continuously press the lever because it is not sure when the next reinforcer (food) will come
2) Pair a US (usually aversive, like a shock) with a CS (a tone)
3) Repeat the first step; the rat will press the lever with the same rate, but if the tone is played, the rat will slow down its lever pressing
4) The rat's fear can be measured by observing how much it slows down its lever pressing

Front 7

Stimulus substitution theory

Back 7

Posited by Pavlov; through repeated pairings of the CS and US, the CS becomes a substitute for the US, so that the UR becomes the CR, and the two are comparable; however, the CR and UR are rarely identical

Front 8

Acquisition phase (classical conditioning)

Back 8

Part of an experiment in which the subject first experiences a series of CS+US pairings and during which the CR gradually appears and increases in strength

Front 9

Asymptote (classical conditioning)

Back 9

Maximum level of responding that is gradually approached as the learning experiment continues; stronger CS+US lead to higher asymptotes and faster conditioning

Front 10

Extinction (classical conditioning)

Back 10

Presenting the CS without the US so that the CR is diminished over time

Front 11

Spontaneous recovery

Back 11

Spontaneous reappearance of a CR after an extinction trial even when no CR is recorded at the end of the extinction trial

Front 12

Inhibition theory of spontaneous recovery

Back 12

After extinction is complete, the animal has two counteracting associations: the excitatory CS+US association formed during acquisition and the inhibitory CS-US association developed during extinction; inhibitory associations are more fragile and can be weakened with passage of time, explaining the spontaneous recovery

Front 13

Conditioned inhibition

Back 13

Any CS that reduces the size of the CR or that reduces the size of the CR from what it would otherwise be.
For example, if a dog is trained to salivate at the sound of a buzzer (+food), a light flash can be introduced, which signals no food. At first, the dog salivates when the buzzer and light are presented together, but eventually, it will only salivate when the buzzer is sounded (learns to discriminate).

Front 14

Generalization

Back 14

Transfer of the effects of conditioning to a similar stimuli; put a pigeon on a VI 5 minute schedule when a green light is shown and measure the number of pecks at different wavelengths to compile an excitatory gradient; peak shift can occur in which responses shift away from the negative stimulus (wavelengths that are not green)

Front 15

Discrimination

Back 15

Subjects learn to respond to one stimulus but not a similar stimulus

Front 16

Rescorla's CER study

Back 16

Rats were divided into three groups: 1) standard pairing (each CS was followed by a US), 2) partial pairing (only some CSs were followed by a US), and 3) random control (some USs without CSs), and CER was performed with all groups. It was found that suppression of lever-pressing was the highest in the rats that underwent standard pairing because this type of conditioning had strong contingency (predictive value) and contiguity.

Front 17

Rescorla-Wagner model equation

Back 17

A mathematical theory of classical conditioning that states that, on each trial, the amount of excitatory or inhibitory conditioning depends on the associative strengths of all the conditioned stimuli that are present and on the intensity of the unconditioned stimulus
DeltaVn = k(lambda - Vn-1)
Lambda = asymptote of conditioning, V = measurement of the CR, n = trial number, k = CS salience (0-1, 1 is most salient)

Front 18

CS pre-exposure effect

Back 18

Classical conditioning will proceed more slowly if a CS is repeatedly presented by itself before it is paired with a US because the subject will ignore the CS since it is not predictive of anything, and it will take a longer time to form the CS+US association; Rescorla-Wagner model does not predict this because it would predict no learning occurs; however, it looks like some does occur

Front 19

Blocking effect

Back 19

One group of rats (blocking group) underwent a CER experiment where light flashes were paired with shocks. In the second phase, the blocking group underwear CER with light flashes + tone + shock. A control group underwent the same procedure. In the testing phase, the tone was presented with no shock to measure the strength of the CS. The blocking group did not react to the tone, but the control group did. This indicates that prior conditioning with the light blocked later conditioning since it added no new information about the US.

Front 20

Basic concepts of the Rescorla-Wagner model

Back 20

Learning will only occur if the subject is surprised.
Strength of US > strength of subject's expectations = excitatory conditioning (acquisition)
Strength of US < strength of subject's expectations = inhibitory conditioning (extinction)
Strength of = strength of subject's expectations = no conditioning, asymptote (blocking)
The larger the discrepancy between the strength of the expectation and the strength of the US, the greater the conditioning that occurs while more salient CSs will condition faster than less salient ones.

Front 21

Thorndike's law of effect

Back 21

Thorndike placed animals inside a cage and measured their escape latency. He found that the behaviors that did not decrease escape latency were decreased while behaviors that decreased escape latency were increased. The greater the satisfaction or discomfort experience by an animal, the more likely or less likely they are to repeat that behavior. Behavior is governed by its consequences.

Front 22

Shaping

Back 22

Method of successive approximations; makes use of a conditioned reinforcer, which is a previously neutral stimulus that has been repeatedly paired with a primary reinforcer; behaviors that approximate the desired behaviors are rewarded.

Front 23

Continuous reinforcement

Back 23

Schedule of reinforcement in which every occurrence of the operant response is followed by a reinforcer; rare in the real world

Front 24

Discrimination hypothesis of schedules of reinforcement

Back 24

In order for a subject's behavior to change once extinction begins, the subject must be able to discriminate the change in reinforcement contingencies; this is difficult to do in schedules of reinforcement other than continuous reinforcement because there is always a time when the reinforcer is not present, so they are resistant to extinction.

Front 25

Generalization decrement hypothesis of schedules of reinforcement

Back 25

An animal on a continuous schedule of reinforcement will show decreased responding when the test stimuli becomes less and less similar to the training stimulus (when the reinforcer is no longer presented every time they make an operant response) since they never learned to continuously respond. Animals on other schedules of reinforcement have learned to continuously respond and see no decrement in the testing stimuli; therefore, these schedules are resistant to extinction.

Front 26

Differential reinforcement of low rates schedule

Back 26

A response is reinforced if and only if a certain amount of time has elapsed since the previous response; the animal cannot perform an operant response before this time

Front 27

Differential reinforcement of high rates schedule

Back 27

A certain number of responses must occur within a fixed amount of time

Front 28

Concurrent schedule

Back 28

Subject is presented with two or more response alternatives, each associated with its own reinforcement schedule

Front 29

Chained schedule

Back 29

Subject must complete the requirement for two or more schedules in a fixed sequence; each schedule is signalled by a different stimulus; strength of responding decreases as a schedule is further and further removed from the primary reinforcer

Front 30

Multiple schedule

Back 30

Subject is presented with two or more different schedules, one at a time, and each schedule is signalled by a different stimulus.

Front 31

Fixed ratio schedule

Back 31

Reinforcer is delivered after every n responses; animal will have a postreinforcement pause (show no responses), which will eventually give way to an abrupt continuation of responding at a constant, rapid rate until the next reinforcer is delivered (i.e. piecework method in factories)

Front 32

Variable ratio schedule

Back 32

Exact number of required responses is not constant from reinforcer to reinforcer; postreinforcement pauses are brief because after each reinforcer there is a possibility that another reinforcer will be delivered after a few responses (i.e., gambling)

Front 33

Fixed interval schedule

Back 33

The first response after a fixed amount of time has elapsed is reinforced; subjects tend to make many more responses per reinforcer than is required; postreinforcement pause occurs, but the subject will begin responding slowly and respond more rapidly the closer it gets to the reinforcer time (i.e., waiting for a bus to show up, and the operant response = staring down the street, looking for the bus)

Front 34

Variable interval schedule

Back 34

The amount of time that must pass before a reinforcer appears varies unpredictably; long pauses after a reinforcer are not advantageous because a reinforcer could appear at any moment; tend to sustain a steady response rate (i.e., checking the mail)

Front 35

Higher order conditioning

Back 35

Does a second CS help the animal predict the US originally paired with the first CS? Pair CS1+US then pair CS1+CS2. This works but a third CS does not work as well.

Front 36

Habituation

Back 36

Decrease in the strength of a response after repeated presentation of a stimulus that elicits a response.