Chapters 5 & 6 – Learning and Memory

Learning vs. Conditioning

• Learning
  • Relatively permanent change in behavior or mental processes caused by experience.
  • What is learned can be unlearned.
• Conditioning
  • Process of learning associations between stimuli and behavioral responses.

Classical Conditioning

• Ivan Pavlov
  • Russian physiologist; discovered classical conditioning while studying dog digestion.

Key Terminology

• Classical Conditioning: Learning through involuntary paired associations. Occurs when a Neutral Stimulus (NS) is paired with an Unconditioned Stimulus (US) to elicit a Conditioned Response (CR).
• Unconditioned Stimulus (US): Stimulus that naturally elicits an Unconditioned Response (UR) without prior learning.
• Unconditioned Response (UR): Unlearned, automatic reaction to the US.
• Neutral Stimulus (NS): Does not naturally evoke the target response before conditioning.
• Conditioned Stimulus (CS): Previously neutral; after repeated pairings with the US, now elicits the response.
• Conditioned Response (CR): Learned reaction to the CS (usually similar to the UR).

Pavlov’s Standard Paradigm (Dog Example)

1. Before Conditioning
   • \text{NS} (Metronome) → No salivation
   • \text{US} (Food) → \text{UR} (Salivation)
2. During Conditioning
   • \text{NS} (Metronome) + \text{US} (Food) → \text{UR} (Salivation)
3. After Conditioning
   • \text{CS} (Metronome) → \text{CR} (Salivation)

Six Principles of Classical Conditioning

• Acquisition
  • Initial learning phase; \text{NS} + \text{US} pairing produces \text{CR}.
• Stimulus Generalization
  • \text{CR} elicited by stimuli similar to \text{CS} (e.g., fear of all dentist offices, not just drill).
• Stimulus Discrimination
  • Differentiating between \text{CS} and similar stimuli; \text{CR} not produced for non-matching stimuli (e.g., physician’s office ≠ dentist’s office).
• Extinction
  • \text{CS} presented without \text{US}; \text{CR} weakens/disappears.
• Spontaneous Recovery
  • Sudden reappearance of an extinguished \text{CR} after time lapse.
• Higher-Order Conditioning
  • New \text{NS} becomes \text{CS} by pairing with an existing \text{CS} (e.g., dentist sign → fear).

Conditioned Emotional Response (Watson’s “Little Albert”)

• Neutral white rat + loud noise → fear.
• Demonstrates conditioning of likes, dislikes, prejudices, phobias, love.

Operant Conditioning

• Definition: Learning in which voluntary behavior is strengthened or weakened by its consequences.

Key Terms

• Reinforcement: Stimulus added (positive) or removed (negative) following a response, increasing likelihood of repetition.
• Punishment: Stimulus added (positive) or removed (negative) following a response, decreasing likelihood of repetition.

Historical Figures

• Edward Thorndike
  • Law of Effect: Responses producing satisfying consequences are stamped in; discomforting consequences are stamped out.
• B. F. Skinner
  • Extended Thorndike’s ideas to complex behaviors; highlighted the centrality of consequences.

Reinforcement (Strengthening Behavior)

• Positive Reinforcement (+): Add desirable stimulus (e.g., baby’s smile, monetary bonus).
• Negative Reinforcement (−): Remove aversive stimulus (e.g., stop baby’s crying, pain relief from aspirin).
  • Both increase behavior frequency.
• Primary Reinforcers: Satisfy biological needs (food, water, touch).
• Secondary Reinforcers: Learned value (money, grades).

Punishment (Weakening Behavior)

• Positive Punishment (+): Add aversive stimulus (extra laps, electric shock).
• Negative Punishment (−): Remove desirable stimulus (loss of dessert, confiscated toy, bonus revoked).
• Primary Punishers: Unlearned, biological (pain, extreme heat).
• Secondary Punishers: Learned (bad grades, fines).

Schedules of Partial (Intermittent) Reinforcement

• Ratio = Response-Based | Interval = Time-Based
  • Fixed Ratio (FR): Reinforcement after predetermined number of responses—high rate with post-reinforcement pause (e.g., free flight after \text{N} miles).
  • Variable Ratio (VR): Reinforcement after varying number of responses—highest, steady rate; resistant to extinction (slot machines).
  • Fixed Interval (FI): Reinforcement after fixed time period—scalloped response pattern (monthly paycheck).
  • Variable Interval (VI): Reinforcement after unpredictable time periods—low steady rate (pop quizzes).

Side-Effects of Punishment

• Passive aggressiveness
• Avoidance behavior
• Inappropriate modeling
• Temporary suppression vs. elimination
• Learned helplessness
• Rewarded & perpetuated aggression

Cognitive-Social Learning

• Emphasizes internal thought processes + social context.

Cognitive Learning

• Insight Learning (Köhler): Sudden “aha!” understanding (e.g., rotate chair sideways through door).
• Latent Learning (Tolman): Hidden learning without immediate behavior; demonstrated when incentive appears (dog sits once offered treat).
• Cognitive Maps: Mental representations of 3-D space navigated.

Observational Learning (Modeling)

• Learning by watching others.
• Four Steps
  1. Attention: Focus on the model.
  2. Retention: Store observation.
  3. Reproduction: Imitate behavior.
  4. Reinforcement/Motivation: Repeat if model (or self) is rewarded.

Memory

Constructive Nature

• Actively organizes & shapes information through encoding → storage → retrieval.

ESR (Encoding–Storage–Retrieval) Model

1. Encoding: Enter data (keyboard analogy).
2. Storage: Save data (hard drive).
3. Retrieval: Access data (open file).

Three-Stage Memory Model

1. Sensory Memory
   • Purpose: hold sensory input.
   • Duration: visual \approx \frac{1}{2} sec (iconic); auditory \approx 4 sec (echoic).
   • Capacity: large.
2. Short-Term / Working Memory (STM)
   • Temporary processing; organizes & sends to LTM.
   • Duration: up to 30 sec without rehearsal.
   • Capacity: 5–9 items; extended via chunking and maintenance rehearsal (repeat, repeat, repeat).
3. Long-Term Memory (LTM)
   • Relatively unlimited capacity & duration.
   • Retrieval sends info back to STM.

Varieties of LTM

• Explicit (Declarative) – conscious recall
  • Semantic: Facts/general knowledge.
  • Episodic: Personal events.
• Implicit (Non-Declarative) – no conscious recall
  • Procedural: Motor skills, habits.
  • Classically Conditioned: Phobias, attitudes.
  • Priming: Earlier exposure facilitates recall.

Improving LTM

1. Mnemonic Devices: Acronyms, method of loci.
2. Organization: Chunking; some occurs during sleep.
3. Rehearsal: Elaborative > maintenance; focus on meaning.
4. Retrieval Cues
   • Specific (recognition) vs. general (recall).
5. Encoding Specificity: Recall improves when context matches learning context.
6. Mood Congruence: Mood at encoding = mood at retrieval.
7. State-Dependent Retrieval: Internal state (e.g., caffeine) consistency aids recall.

Forgetting

• Ebbinghaus Curve: Rapid initial drop, then levels.
• Relearning is faster than first learning.
• Optimal practice occurs just before forgetting would happen.

Reasons for Forgetting

• Encoding Failure: Never entered LTM.
• Decay / Disuse: Memory trace fades over time.
• Proactive Interference: Old info disrupts new.
• Retroactive Interference: New info disrupts old.

Memory Loss & Disorders

• Traumatic Brain Injury (TBI)
  • Leading neurological disorder (ages 15–25); causes include car accidents, falls, gunshots.
  • Amnesia: Memory loss due to brain trauma.
• Alzheimer’s Disease
  • Progressive deterioration; severe decline in explicit/declarative memory.
  • Implicit/procedural memory often spared in early stages.