Flashcards in Chapter 8 - Stimulus Control of Behavior Deck (43):
How do you experimentally determine whether instrumental behavior has come under the control of a particular stimulus?
The stimulus control of instrumental behavior is demonstrated by variations in responding (differential responding) related to variations in stimuli. If an organism responds one way in the presence of one stimulus and in a different way in the presence of another stimulus, its behavior has come under the control of those stimuli.
Stimulus discrimination (definition)
Differential responding to two different stimuli.
An organism is said to exhibit stimulus discrimination if it responds differently to two or more stimuli
Stimulus generalization (definition)
An organism is said to show stimulus generalization if it responds in a similar fashion to two or more stimuli
Stimulus generalization is the opposite of differential responding.
Stimulus generalization gradient (definition)
A gradient of responding that is observed if participants are tested with stimuli that increasingly differ from the stimulus that was present during training
Some ways to increase generalization of behavior therapy
1) The treatment situation should be made as similar as possible to the natural environment of the client.
2) Generalization also may be increased by conducting the treatment procedure in new settings (sequential modification)
3) Using numerous examples during training
4) Conditioning the new responses (CR) to stimuli that are commonly present in various situations
5) Make the training procedure indiscriminable or incidental to other activities
6) Generalization outside a training situation is achieved if the training helps to bring the individual in contact with contingencies of reinforcement available in the natural environment.
What is the central issue in analysis of stimulus control?
What determines which of the numerous features of a stimulus situation gains control over the instrumental behavior
What is sensory capacity?
The ability of an organism to perceive certain stimuli is a factor in determining what particular feature of a stimulus controls responding
Interference with the conditioning of a stimulus because of the simultaneous presence of another stimulus that is easier to condition
How does reinforcement relate to stimulus control?
The development of stimulus control depends on the type of reinforcement that is used.
Certain types of stimuli are more likely to gain control over the instrumental behavior in appetitive than aversive situations.
Visual vs auditory control
Visual control predominates when the CS acquires positive or appetitive properties (visual cues for food activate the feeding system, food eaten by pigeons and rats is more likely to be identified by visual cues)
Auditory control predominates when the CS acquires negative or aversive properties (responding to auditory cues may be adaptive in avoiding danger - activation of defensive behavior system)
An approach to the analysis of control by compound stimuli which assumes that participants respond to a compound stimulus in terms of the stimulus elements that make up the compound
An approach to the analysis of stimulus control which assumes that organisms respond to a compound stimulus as an integral whole rather than a collection of separate and independent stimulus elements.
What other aspect of stimuli do you need to consider in stimulus control other than whether the stimuli can be detected?
Whether or not certain stimuli come to control behavior depends on what the individual has learned about those stimuli, not just whether the stimuli can be detected
How did Lashley and Wade disagree with Pavlov?
In contrast to Pavlov, Lashley and Wade considered the shape of a stimulus generalization gradient to be determined primarily by the organism's previous learning experiences rather than by the physical properties of the stimuli tested
What does a graph of stimulus discrimination training look like?
The conditioned responding that develops to A+ generalizes to B- at first, but with further training responding to B- declines and a clear discrimination becomes evident
Stimulus discrimination procedure - classical conditioning (definition)
A classical conditioning procedure in which one stimulus (the CS+) is paired with the US on some trials and another stimulus (the CS-) is presented without the US on other trials. As a result of this procedure, the CS+ comes to elicit a conditioned response and the CS- comes to inhibit this response.
Stimulus discrimination procedure - instrumental conditioning (definition)
A procedure in which reinforcement for responding is available whenever one stimulus (the S+, or SD) is present and not available whenever another stimulus ( the S-, or Sdelta) is present
discriminative stimulus (definition)
A stimulus that controls the performance of instrumental behavior because it signals the availability (or nonavailability) of reinforcement.
The S+ is a discriminative stimulus for performing the instrumental response and the S- is a discriminative stimulus for not performing the response
What conclusions do the Jenkins and Harrison experiments provide?
Discrimination training increases the stimulus control of instrumental behavior.
A particular stimulus dimension (such as tonal frequency) is most likely to gain control over responding if the S+ and S- differ along that stimulus dimension.
The 1000 and 950 cps tone trial pigeons had the steepest generalization gradient and thus the strongest stimulus control
positive patterning (definition)
A discrimination procedure in which reinforcement is provided when two stimuli (A and B) are presented simultaneously (AB+) but not when those stimuli appear by themselves (A- and B-).
negative patterning (definition)
A discrimination procedure in which reinforcement is provided when each of two stimuli appear by themselves (A+ and B+) but not when the two stimuli appear simultaneously (AB-).
What did Spence say about discrimination learning?
That suppression of responding evident in the experimental group shows that a stimulus that is a signal for nonreinforcement (S-) in a discrimination procedure acquires active inhibitory properties
What do discoveries regarding inhibitory processes in discrimination learning have to do with addiction
Drug seeking can be reduced by inhibition even if excitatory processes remain intact.
What does it mean for S+ and S- to be related?
S+ and S- might be related if they are similar except for one feature or attribute.
A discrimination between stimuli that differ only in terms of the value of one stimulus feature, such as color, brightness, or pitch
peak-shift effect (definition)
A displacement of the highest rate of responding in a stimulus generalization gradient away from the S+ in a direction opposite the S-.
1) The peak-shift effect is a result of intradimensional discrimination training
2) The peak-shift effect was a function of the similarity of the S- to the S+ used in discrimination training
excitatory generalization gradient (definition)
A gradient of responding that is observed when organisms are tested with the S+ from a discrimination procedure and with stimuli that increasingly differ from the S+. Typically the highest level of responding occurs to stimuli similar to the S+; progressively less responding occurs to stimuli that increasingly differ from the S+. Thus, the gradient has an inverted-U shape.
How does Spence explain the peak-shift effect?
Because of overlap, inhibition to S- may generalize to S+ and suppress responding to S+, resulting in a peak-shift effect. More inhibition from S- to S+ is expected if S- is closer to S+ and this should result in a greater peak-shift effect.
stimulus equivalence (definition)
Responding to physically distinct stimuli as if they were the same because of common prior experiences with the stimuli.
common outcome training (definition)
Involves linking each of several different stimuli to a common outcome.
common response training (definition)
Involves training the same response to several physically different stimuli.
common response training diagram
Initial training - animals learn that (A1, A2, A3, A4) and (B1, B2, B3, B4) elicit R1 which is reinforced by food
Reassignment - animals learn that (A1, A2, A3, A4) elicit R3 which is reinforced by food
Test - see if (B1, B2, B3, B4) elicit R3
If A leads to B (A -> B) then symmetry requires that B leads to A (B -> A)
How do contextual cues control behavior?
Contextual cues can come to control behavior if they serve as a signal for a US or a reinforcer
Contextual cues can develop without one context being more strongly associated with reinforcement than another.
conditional relation (definition)
A relation in which the significance of one stimulus or event depends on the status of another stimulus.
Ex: if context 1, then 90+/0- and if context 2, then 90-/0+
What does lesioning the hippocampus do to context conditioning
It eliminates the capacity of context conditioning without affecting the capacity to learn that a discrete cue (e.g., a tone) predicts shock)
This is because fear conditioning depends upon the basolateral region of the amygdala
perforant path and mossy fibers
Stimulating axons of the perforant path shows that a strong input produced a long-lasting increase in the response elicited in cells of the mossy fiber pathway
AMPA receptors vs NMDA
AMPA are associated with action potentials (Na+)
NMDA are associated with Ca++ influx after Mg++ is displaced
A stimulus that signals the relation between two other events. A modulator may signal that a CS will be followed by a US or that an instrumental response will be reinforced. The modulator is part of a conditional relation in which the status of a binary relation depends on the status of the modulator.
the relation of a modulator to the binary relation that it signals
A procedure in which one cue designates when another cue will be reinforced