Classical Conditioning
How can one event acquire meaning because it reliably predicts another?
Prediction changes meaning
Think of a neutral cue that can acquire meaning because it repeatedly predicts something else: a school bell, notification sound, smell, song, or place. What does the cue predict?
What relationship was learned?
By the end of today
- Distinguish US, UR, CS, and CR.
- Explain acquisition as learning a predictive relationship.
- Explain extinction without treating it as erasure.
- Apply spontaneous recovery, generalization, and discrimination.
- Evaluate whether classical conditioning is actually supported by evidence.
conditioned stimulus
Formal definition
A previously neutral stimulus that, after a predictive relationship is learned, elicits a conditioned response.
Student-friendly definition
A cue that gains learned meaning because it predicts another event.
Classical-conditioning language
US / UR
An unconditioned stimulus naturally elicits an unconditioned response without the relevant learning history.
Neutral stimulus / CS
A cue initially lacking the conditioned meaning can become a conditioned stimulus after learning.
CR
The learned response elicited by the conditioned stimulus.
Acquisition
The period in which the predictive relationship is learned.
Extinction / spontaneous recovery
The conditioned response weakens when the CS no longer predicts the US; an extinguished response may later reappear.
Generalization / discrimination
Generalization spreads responding to similar cues; discrimination distinguishes among cues.
Conditioning is learning about prediction
Classical conditioning occurs when organisms learn that one event predicts another. Before conditioning, an unconditioned stimulus can produce an unconditioned response without the relevant learned association. A neutral stimulus does not initially have that predictive meaning. During acquisition, the neutral cue is paired with or otherwise reliably signals the important event. After learning, the cue becomes a conditioned stimulus capable of eliciting a conditioned response.
Timing and predictiveness matter. Two events simply occurring together does not guarantee strong conditioning. A cue that reliably signals when an event will occur is more informative than a cue that appears randomly whether or not the event happens.
Extinction occurs when the conditioned stimulus repeatedly appears without the event it once predicted and the conditioned response weakens. Extinction should not be described as deleting the original learning. Spontaneous recovery—the reappearance of some conditioned responding after time has passed—shows why that language is too simple.
Generalization allows similar cues to elicit related responses. Discrimination occurs when learning becomes specific enough that one cue predicts the outcome while another does not. Both can be adaptive. Generalization can prepare an organism for similar situations; discrimination prevents responding to every vaguely similar cue.
Classical conditioning can contribute to emotional and physiological responses without deliberate conscious choice. But an emotional response is not proof of conditioning. Biology, appraisal, memory, social context, and other learning processes can also contribute.
Tone and food
Before learning: food (US) → salivation (UR). Tone = neutral.
During acquisition: tone + food → salivation.
After learning: tone (CS) → conditioned salivation (CR).
The tone now predicts food. The learning is about that relationship.
Claim audit
Classical conditioning can contribute without deliberate choice. But the observed reaction still does not reveal its full cause. Evidence must distinguish conditioning from biological, cognitive, developmental, and situational alternatives.
Acquisition and extinction
| Trial | Conditioned response strength |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 7 |
| 6 | 8 |
| Extinction 1 | 7 |
| Extinction 4 | 3 |
| Extinction 8 | 1 |
“Any repeated pair of events becomes conditioned.”
Verdict
Too broad. Timing, predictiveness, salience, prior learning, and biological constraints matter.
Better statement
Conditioning is stronger when a cue reliably predicts an outcome under conditions that support learning.
Six conditioning cases
For each fictional case, identify the US, UR, CS, CR, evidence of learning, and one alternative explanation.
Generalization & discrimination
Write two original fictional conditioning cases. One must demonstrate generalization and one discrimination. Explain the predictive relationship and why the evidence fits the concept.