Lecture 9 - Stimulus Control Flashcards
What is stimulus discrimination?
Differential responding to two stimuli
What is stimulus generalisation?
Stimulus generalization is the opposite of differential responding, or stimulus discrimination. An organism is said to show stimulus generalization if it responds in a similar fashion to two or more stimuli.
What is a stimulus generalization gradient?
a gradient of responding as a function of how similar each test stimulus was to the original training stimulus
the steepness of a stimulus generalization gradient provides a precise measure of the degree of stimulus control
What are the Stimulus and Reinforcement Variables affecting stimulus control?
Sensory Capacity and Orientation
Relative Ease of Conditioning Various Stimuli (overshadowing)
Type of Reinforcement
Stimulus Elements Versus Configural Cues in Compound Stimuli
What is the stimulus-element approach?
treating the simultaneous presentation of a light and tone as consisting of separate visual and auditory cues
What is the configural-cue approach?
treating a compound stimulus as an integral whole that is not divided into parts or elements
Stimulus Discrimination Training
What is the Effects of Discrimination Training on Stimulus Control?
Narrowing of generalisation gradient
What are the mechanisms of stimulus control by drug stimuli?
Discrimination Training Focused on Interoceptive Cues
similar to the mechanisms for the control of key pecking by auditory cues in pigeons
What are the types of Discrimination Training Focused on Compound or Configural Cues?
positive patterning
A- B- AB+
negative patterning
C+ D+ CD-
Not fast but evident learning
What Is Learned in Discrimination Training
What is Spence’s Theory of Discrimination Learning?
The theory assumes that reinforcement of a response in the presence of the S+ conditions excitatory response tendencies to S+. By contrast, nonreinforcement of responding during S– conditions inhibitory properties to S– that serve to suppress the instrumental behavior. Differential responding to S+ and S– reflects both conditioned excitation to S+ and conditioned inhibition to S–
Interactions Between S+ and S–: The Peak-Shift Effect
What type of discrimination is involved?
intradimensional discrimination
S+ and S– differ only in terms of the value of one stimulus feature
What is Spence’s Explanation of Peak Shift?
When S+ and S– are both colors, the generalization gradients of excitation and inhibition may overlap, with the degree of overlap depending on the degree of similarity between S+ and S–. Because of this overlap, inhibition to S– may generalize to S+ and suppress responding to S+, resulting in a peak-shift effect
What is an Alternative Account of Peak Shift?
(Spence’s model of discrimination learning is an absolute stimulus learning model. It predicts behavior based on the net excitatory properties of individual stimuli.)
The alternative approach assumes that organisms learn to respond to a stimulus based on its relation to other cues in the situation
What are some methods of Stimulus Equivalence Training?
common outcome training
common response training
What are the properties of an equivalence class?
Reflexivity/sameness - A = A, B = B, and C = C.
Symmetry - relationship is bidirectional.
Transitivity - integration of two relationships into a third one.
