LPI Topic 5 Flashcards
Rescorla–Wagner Model (1972)
A mathematical model explaining classical conditioning based on prediction errors. Learning occurs when an outcome is unexpected.
Rescorla–Wagner Model (1972) Formula
ΔV = Change in associative strength
𝛼 = Salience of the conditioned stimulus (CS)
𝛽 = Learning rate of the unconditioned stimulus (US)
𝜆 = Maximum associative strength (1 = US present, 0 = US absent)
∑𝑉= Sum of associative strengths of all present stimuli
Key Predictions of Rescorla–Wagner Model
- Blocking
- Cue Competition
- Conditioned Inhibition
Blocking
If a stimulus (A) already predicts an outcome, introducing another stimulus (B) will not lead to learning about B.
Cue Competition
When multiple stimuli are presented together, they compete for associative strength with the outcome.
Conditioned Inhibition
A stimulus predicting the absence of an outcome can reduce responses to another predictive stimulus.
Kamin’s Blocking Experiment (1969)
An experiment showing that learning does not occur when an outcome is already fully predicted.
Kamin’s Blocking Experiment (1969) Procedure
- Phase 1: A tone (CS1) is paired with a shock (US) – the rat learns to fear the tone.
- Phase 2: A light (CS2) is introduced along with the tone, still predicting the shock.
- Test: When the light is presented alone, the rat does not react, showing no learning occurred.
- Conclusion: Learning depends on surprise—if an outcome is fully expected, no learning happens.
Unblocking (Overcoming Kamin’s Blocking)
- If unexpected events occur (e.g., increasing shock intensity in Phase 2), learning resumes.
- Learning is driven by surprise—bigger surprises create stronger learning.
Dopamine and Learning by Prediction Errors
- Definition: Dopamine neurons signal prediction errors, adjusting behaviour based on expected vs. actual outcomes.
Key Findings (Schultz, 2007):
- Unexpected rewards trigger a dopamine spike.
- With repeated learning, dopamine shifts to the predictive cue (CS).
- If a reward is missing, dopamine drops, signalling a negative prediction error.
Dopamine in the Blocking Paradigm
- When a blocked stimulus is presented, no dopamine activity is detected.
- Supports the idea that learning requires unexpected outcomes.
Classical Conditioning in Drug Tolerance & AddictionClassical Conditioning in Drug Tolerance & Addiction
- Conditioned Compensatory Response (CCR): The body anticipates drug effects and counteracts them.
Example:
- CS: Needle, environment, people associated with drug use.
- US: The drug itself.
- UR: Direct drug effect (e.g., sedation, euphoria).
- CR: Opposite bodily response (e.g., increased alertness to compensate for drug effects).
Tolerance & Overdose
- Tolerance: CCR weakens drug effects over time.
- Overdose: If a drug is taken in a new environment, no CCR occurs, making the usual dose dangerous.
Heroin Overdose Mystery (Siegel, 2016)
- Case Study: A heroin user takes their usual dose in a new environment and overdoses.
- Explanation: Without familiar cues to trigger CCR, the body fails to prepare for the drug’s effects.
Learning Theory Approach to Personality
Personality is shaped by learning through reinforcement, observation, and expectations.
Rotter (Locus of Control)
- Internal locus of control: Belief that personal effort determines success.
- External locus of control: Belief that luck or fate determines success.
Mischel (Delayed Gratification)
Self-control is influenced by learning experiences (e.g., marshmallow test).
Mischel & Shoda (CAPS Model)
Personality is shaped by situational interactions and stable individual differences.
Criticism of Learning Theory in Personality
- Too simplistic—does not account for genetic and biological influences.
- Over-reliance on animal research, which may not generalise to humans.
