Psych of Learning: Stimulus Control – Flashcards

When certain stimuli determine whether a certain response is performed.

2 pigeons were reinforced on a VI schedule for pecking a red circle key with a white triangle. Reinforcement became available when the key was lit up. The pigeons were trained to peck at the triangle for food. Once trained, Reynolds presented either the red circle or the white triangle to see which one pigeons responded to more. The results were varied, which indicates that there was very little stimulus control over behavior.

The stimulus control of instrumental behavior is demonstrated by variations in responding related to variations in stimuli.

Differential responding to two or more stimuli

Simliar responding to two or more stimuli

Both discrimination and generalization deal with the sensitivity of an organism's response to various stimuli. Discrimination and generalization are essentially opposites. Where discrimination makes responding more specific to a stimulus, generalization makes responding more generalized to stimuli.

Graph responding as a function of how similar each test stimulus is to the original test stimulus. A generalization gradient will provide precise information as to how sensitive an organism's behavior is to variations in a particular aspect of the environment.

The steepness of a generalization gradient gives you a precise measure of the degree of stimulus control attached to each stimulus. A steep generalization gradient means good control of behavior by the stimulus dimension that is tested - responding is differentiated between the two stimuli. A flat generalization gradient means poor control of behavior by the stimulus that is tested.

It would be flat.

1) Poor perception or attention to a stimulus. - for example, a colorblind horse can't perceive colors. 2) Very generalized responding.

The goal of treatment programs is to make treatment as close to the subject's natural environment as possible. - reduce the frequency of reinforcement during training sessions - use the same reinforcers as the subject is likely to encounter in their natural environment anorexia: S+ would be average weight, and S- would be heavy weight. fear of heights: learn to generalize between different heights

Should be as similar as possible to the subject's natural environment. - conduct behavior in various settings (sequential modification) - use numerous examples during training (fear of elevators - use lots of elevators!) - make the behavior instrumental or indiscriminable with other activities (if you're trying to teach a child the names of dolls, just have them play with the dolls and they'll learn the names in the process or if you're trying to teach a child with autism how to interact with other children in social situations, use ball skills) - bring subject into contact with contingencies of reinforcement that are available in their natural environment (so once a response is acquired through special training, it can be reinforced in normal circumstances. Like arithmetic or riding a bike)

Sensory capacity and orientation Salience/overshadowing - the relative ease of conditioning various stimuli Prior conditioning/blocking Reinforcement type (appetitive or aversive pairings with pigeons) Response type (quality-location effect with dogs) Stimulus Elements vs. Configural Cues Predictive validity Belongingness/cue consequence specificity Equivalence training (training a common outcome or response)

Sensory capacity determines which stimuli are included in an organism's sensory world, so if a stimuli is out of a subject's sensory capacity (like high pitched tones that humans cannot hear but dogs can, or a horse's inability to detect the color red)

Overshadowing

Pigeons for appetitive stimulus (food) pigeons paid more attention to visual cues. for aversive stimulus (shock avoidance) pigeons paid more attention to auditory cues. Both tendencies are likely a result of adaptive tendencies, where visual cues are more relevant to food-finding, and auditory cues are more relevant to detecting danger.

Dogs Dogs trained on a left/right leg left pattern responded more to locational tone cues. Dogs trained to lift one leg when they heard one type of cue, and not lift their lift their leg when they heard the other type, responded more to the quality of the tone. The nature of a response can affect which stimuli come control behavior.

A compound cue that the organism experiences as a whole.

When listening to an orchestra, you will tend to hear the greater symphony and not the individual instruments.

There are two ways to conduct discrimination training: Classical: you would pair a CS with a US (a high-pitched tone with a puff of air). You would pair a low pitch with no air-puff. Rats learned to respond 85% more to the high pitch, meaning that rats ended up discriminating their behavior to the high pitch tone, and away from the low pitch tone. Instrumental: how you would teach a child to respond to traffic lights. Children are reinforced when they cross at the walk signal, and not reinforced when they cross at the "do not walk" signal.

Discrimination training will make generalization gradients steeper, because it lessens generalized responding.

Some sensory-cues will be within an organism's sensory capacity, and it will therefore be possible to manipulate animal's behavior in discrimination training. Other sensory cues though will fall outside of an organism's sensory capacity, or it may be less sensitive to it, in which case discrimination training wouldn't work and generalization gradients would remain relatively flat.

Spence argued that discrimination training works as a result of both increased responding around the S+ and inhibitory responding around the S-.

A shift in the highest rate of responding on a generalization gradient away from the S+ and in a direction opposite the S-. Can be thought of as overcompensating. And peak shift tends to be greater if responses are more similar to one another for this reason.

The simultaneously excitatory (S+) and inhibitory (S-) gradients affects peak shift as the two gradients cross. In intradimensional stimulus training, the more similar the S+ and the S- are to one another (for example greater similarity in tonal frequency) the more likely it is that peak shift will occur.

Subjects learn to respond to stimuli based on its relative size. So if S+ is much bigger than S-, the subject learns to respond to S+ based on its relative size in comparison to S- rather than its absolute size. When the sizes are much closer together peak shift happens because it's harder to distinguish between the two stimuli. This approach is a configure one rather than an elemental one.

The pairing of different stimuli with the same outcome creates functional equivalence between those stimuli, with the result that subjects come to respond to all stimuli in a stimulus class in the same fashion. Equivalence training encourages generalized responding. Equivalence training is important for concept formation where it comes to expertise, where telling minute differences between things is important.

An equivalence class consists of 3 properties Reflexivity/sameness: A = A Symmetry: If A=B then B=A Transitivity: If A=B and B=C then A=C Equivalence classes are important in language where the word "apple" = picture of an apple, and an actual apple. All of these descriptive signifiers are part of one equivalence class, which is "apple."

Behavior can be modulated by contexts. For example, it is easier to study in a library than at home or over the holidays, and one is more likely to cheer at a football game than in church.

Contextual cues come to control behavior when they serve as a signal for a US or a reinforcer. But contextual cues can also come to control behavior when they are just background, and there is no particular reinforcer associated with it.

A conditional cue is a modular in that it is conditionally related to a binary relation.

A third stimulus that facilitates or signals the association between two other stimuli.

A modulator is actually in some ways the conceptual opposite of an inhibitor in that at modulator is attached to a stimulus that triggers a reinforced response, where an inhibitor is attached to a stimulus that triggers non-responding.

While modulators work to signal the forthcoming presentation of an excitatory cue, a modulator on its own does not stimulate behavior. Further, during extinction training, getting rid of the modulator didn't change responding, while altering the relation between the CS and the US did.

1) B would come to be the only stimulus that controls (overshadowing) 2) AB would be registered as a configuration (as a configural cue) rather than by its individual elements 3) B would serve as a modulator for the presentation of A