Chapter 13

critical feature of normal adaptive behavior
Examples:
- Hugging a friend or family member is appropriate, but not a stranger.
- Taking a snack and putting it into your pocket is acceptable when departing from home, but not when departing from a grocery store.

Environmental stimuli are complex; for instance:
- Stoplights vary in colors, shapes, brightness, and positions.

Differential Responding (alternation): Response controlled by stimulus if the response is altered after changes in that stimulus. This alteration is termed differential responding and is crucial for determining stimulus control.

Sensory Capacity: Limitations of an organism's perception.
- Example: Humans cannot respond to sounds above 20,000 cycles/sec, whereas dogs can.
Limitations of Sensory Capacity: It's merely a precondition; it does not guarantee influence on behavior by any particular stimulus.
Sensory Orientation: Concerns how accessible a stimulus is to the relevant sense organ. For example:
- To perceive a small stimulus, an organism must orient itself towards it.
- Ambient sounds and lights continuously affect the environment regardless of the organism's orientation, thus often used in experiments.

Stimulus Intensity: Intense stimuli are more likely to gain behavioral control than weak ones.
- Intense stimuli lead to more rapid learning and more vigorous responses.
Overshadowing: Occurs when intense stimulus gains control at the expense of a weaker stimulus.
Motivational State: Changes in the emotional state of an organism can shift attention from one stimulus to another, functioning as a form of filtering.

Behavior is influenced by the significance of a stimulus. Two conditioning types ensure significance:
1. Pavlovian Conditioning: Establishes association between a CS and an US, making an initially unimportant stimulus significant.
2. Instrumental Conditioning: Establishes significance based on responses to specific features of the environment, such as a lever or response key.
Limitations: These procedures cannot determine which aspects of the environment will be most significant, hence the role of explicit discrimination training.

Stimulus control involves:
1. Discrimination: Responding differently to different stimuli.
2. Generalization: Responding similarly to different stimuli.
These two phenomena are considered two sides of the same coin.
Methods of Discrimination and Generalization:
- Different methods exist for teaching these concepts, including simultaneous and successive discrimination methodologies.

Simultaneous Discrimination: Responding to stimuli presented at the same time.
Successive Discrimination: Conducting trials where stimuli are presented one after the other, emphasizing learning across a series of trials.

STIMULUS GENERALIZATION GRADIENT TESTING - Conduct training on a Variable Interval (VI) schedule and test randomly on an extinction (EXT) schedule to investigate generalization gradients.

Stimulus discrimination training - Involves differential reinforcement in the presence of various stimuli, leading to different outcomes based on exposure to these stimuli.
Requires at least two stimuli in both Pavlovian and Instrumental conditioning procedures.
- Differential reinforcement associates the unconditioned stimulus (US) or reinforcer with one cue (S+), but not with another cue (S-).

Initial generalization occurs where responding to S+ is extended to S-.
- Over time, response to S+ increases while response to S- decreases, resulting in strong discrimination between the two responses.
In INSTRUMENTAL SUCCESSIVE DISCRIMINATION TRAINING, target response is reinforced ONLY in the presence of S+, NOT S-.
Training consists of procedures such as S+ → R → O trials and S- → R → No O trials, utilizing a multiple schedule of reinforcement.

Stimulus generalization - defined by reinforced responding to one stimulus also occurring for other similar stimuli.
Generalization gradients reflect how steep gradients indicate stronger control by specific stimulus dimensions:
- STEEP Gradient = STRONG Control
- shallow Gradient = weak Control

Pavlov's Theory: Spread-of-effect - activation in one brain area influences nearby regions.
Lashley & Wade's Theory (1946): Generalization occurs due to the organism not having learned to distinguish between stimuli.
Implication: If correct, discrimination training can modify stimulus generalization rates.

SPENCE’S THEORY OF DISCRIMINATION LEARNING - Centers on the association of excitation and inhibition with S+ (reinforced) and S- (nonreinforced) stimuli.
Paired with reinforcement, a gradient of excitation develops around a stimulus, with the peak excitation at the training stimulus, decreasing orderly with distance.
Paired with nonreinforcement results in a gradient of inhibition surrounding that stimulus, with similar orderly decreases.

Honig studied pigeons trained with varying line stimuli and observed predicted behaviors aligning with the peak shift phenomenon, demonstrated Spence’s theory.
Peak Shift Phenomenon: The predicted peak of intradimensional generalization gradient shifts away from S+ towards points distinct from S-.

Acquired Distinctiveness: Increased precision in stimulus control resulting from differential reinforcement, which decreases generalization.
Acquired Equivalence: A decrease in precision of stimulus control often arising from non-differential reinforcement, which increases generalization.
These concepts bolster Lashley & Wade's assertion of learning's crucial role in stimulus control, particularly in perceptual concept learning.

Discrimination between compound stimuli (e.g., AX and BX) can be taught through differential reinforcement or through repeated exposure for habituation leading to familiarity, but differential reinforcement is faster.

STIMULUS EQUIVALENCE TRAINING -Trains participants to respond similarly to different stimuli (e.g., a square and circle), promoting generalization but slowing later discrimination.
In perceptual concept learning, responding uniformly across varied perceptually distinct stimuli creates equivalence classes (e.g., naming all fruits similarly) and supports the theory of learning significantly affecting stimulus control.

Response timing and location are determined by stimulus control which involves differential responding measured by the steepness of generalization gradients across training procedures.
Influencing factors include:
- Sensory capacity
- Sensory orientation
- Stimulus intensity
- Motivational state
- Emotional state.
Overall role of Discrimination Training: The primary mechanism for establishing stimulus control; can involve both interdimensional and intradimensional stimuli, with the latter yielding more acute stimulus control in expert performances such as wine tasting.
Importance of Stimulus Equivalence: Essential in various learning contexts such as simple equivalence, perceptual concept learning, language acquisition, and applied behavioral analysis.