Psychology 100: Learning & Memory

Psychology 100: Learning & Memory

Definition of Learning and Memory

• Learning

  • Defined as a lasting change in behavior resulting from experience.

• Memory

  • Consists of information that is encoded and stored in the brain resulting from a learning experience.

  • Not visible externally; inferred through observable behavioral changes following experiences.

Who Can Learn & Remember?

• The nervous systems exhibit plasticity, implying that changes can occur in response to experiences.

Multiple Kinds of Learning

• Types of Learning:

  • Simple Associations (e.g., responding to commands like "Sit!")

  • Motor Skills (e.g., complex actions)

  • Complex Skills (e.g., classical & operant conditioning)

  • Cognitive Skills

Classical Conditioning

Overview

• Also known as Pavlovian Conditioning.

Ivan Pavlov

• A Russian physiologist recognised for studying the digestive processes.

• Nobel Prize: Won in 1904 for his discoveries that contributed to the study of conditioned reflexes and behavior associations in the brain.

• Developed a series of laboratory instruments, including:

  • Saliva collection chamber

  • Response recording device

  • Food container

  • Saliva collection tube

  • Observation screen

Key Terms in Classical Conditioning

1. Unconditioned Stimulus (UCS): Stimulus that naturally and automatically triggers a response (e.g., presentation of food).

2. Unconditioned Response (UCR): The unlearned response that occurs naturally in reaction to the UCS (e.g., salivation in response to food).

Conditioning Process

• Phase 1 (Before Conditioning)

  • Presentation of food (UCS) triggers the salivation response (UCR).

• Phase 2 (During Conditioning)

  • Pairing a neutral stimulus with UCS leads to feelings of hunger, autonomic reflexes, hormone release.

• After Conditioning:

  • Conditioned Stimulus (CS): Previously neutral stimulus (like a bell) that starts to trigger a learned response, now called the Conditioned Response (CR).

  • Example: The bell gains meaning, prompting salivation in anticipation of food.

Higher-Order Classical Conditioning

• Chaining Associations Together: Enables more complex associations through further pairings with CS.

  • Example structure:

  • PHASE #1: Presentation of food (UCS) + Conditioned Stimulus (CS1)

  • PHASE #2: CS1 is now referred to as CS2, creating a second-order association.

Extinction of Conditioned Responses

• A conditioned response will extinguish if the conditioned stimulus is no longer paired with the unconditioned stimulus.

• Strength of CR (e.g., amount of saliva decreases) will drop over trials where no pairings occur.

Real-World Applications of Classical Conditioning

• Acquired 'likes' and 'dislikes': Preferences to tastes, smells, situations, etc.

• Emotional reactions: Learned fears, anxieties, joys, disgust, etc.

• Automatic thinking patterns may develop biases and stereotypes related to stimuli associated with emotions.

The Case of “Little Albert”

• An experiment by Watson & Rayner (1920) exploring conditioned emotional reactions.

• Process outlined:

  • Before Conditioning: Exposure to a white rat (neutral stimulus).

  • During Conditioning: Paired white rat with a loud noise (UCS), provoking fear (UCR).

  • After Conditioning: White rat (CS) elicits a conditioned fear response (CR) involving behavioral, emotional, physiological, and hormonal reactions.

Operant Conditioning

Overview

• Also referred to as Instrumental Conditioning.

Edward Thorndike

• Pioneer in educational psychology.

- Studied learning processes using trials with "puzzle boxes" to observe behavior.

Law of Effect:

• States that organisms learn from the consequences of their actions.

• Behaviors leading to good outcomes are repeated, while those leading to bad outcomes are avoided.

Thorndike’s Puzzle Boxes

• Design where cats had to perform specific actions (like pressing a pedal) to escape and receive food as a reward.

• Demonstrates trial-and-error learning.

Learning Curve

• Illustrates how trial-and-error learning improves efficiency over time, characterized by a gradual increase in successful behaviors.

The “Law of Effect” Visual

• Likelihood of Behavior Repeating:

  • If something rewarding follows behavior, it increases likelihood.

  • If something punishing follows behavior, it decreases likelihood.

B.F. Skinner and Operant Conditioning

• Defined an operant as a voluntary behavior that acts upon the environment.

• Used the Skinner Box to study reinforcement.

  • Contains features like a food pellet dispenser, lever for bar pressing (operant), and environmental controls.

Reinforcement

• Reinforcement leads to increased behavioral responses:

  • Positive Reinforcement: Receiving something desirable post-behavior (e.g., food).

  • Negative Reinforcement: Removal of something undesirable post-behavior (e.g., escape from confinement).

Types of Reinforcement

1. Primary Reinforcers: Require no prior experience for value (e.g., food, water).

2. Secondary Reinforcers: Acquire value through classical conditioning linked with primary reinforcers (e.g., money, praise).

Neurobiology of Reinforcement

• Dopamine: Critical to reinforcement processes, particularly in the nucleus accumbens (the brain's reward center).

• Involvement of brain structures:

  • Hypothalamus: Regulates life-sustaining drives and links to the endocrine system.

  • Hippocampus: Involved in memory formation.

  • Amygdala: Plays a role in emotion and threat response.

Punishment

• Leads to a decrease in behavioral responses:

  • Positive Punishment: Introduction of an aversive stimulus post-behavior (e.g., physical punishment).

  • Negative Punishment: Removal of a pleasant stimulus post-behavior (e.g., taking away privileges).

Extinction in Operant Conditioning

• Previously reinforced behaviors can extinguish if reinforcement is withdrawn.

B.F. Skinner’s Insights on Reinforcement

• Emphasizes that the execution style of positive reinforcement is more crucial than the amount of reinforcement provided.

Schedules of Reinforcement

• Details on how reinforcement is generally not provided continuously, rather through ratio or interval schedules, impacting behavior response rates.

Types of Schedules

1. Fixed Interval Schedule: Provides reinforcement after a set time.

   • Example: Payroll periods, studying habits, which can lead to varying response patterns.

2. Variable Interval Schedule: Rewards at unpredictable times.

   • Example: Checking social media or email, leading to steady, frequent responding.

3. Fixed Ratio Schedule: Reinforcement after a specific number of responses.

   • Example: Loyalty cards or commission-based earnings.

4. Variable Ratio Schedule: Unpredictable reinforcement after an average number of responses.

   • Example: Gambling behavior and how it leads to persistent responding.

Extinction Susceptibility Summary

• Likelihood of extinction varies with the reinforcement schedule used.

  • Continuous: Very easy to extinguish.

  • Fixed/Variable Interval: Relatively easy to extinguish.

  • Variable Ratio: Very difficult to extinguish due to unpredictability.

Behaviorism’s “Black Box” Concept

• Emphasizes that internal mental states (e.g., thoughts and feelings) are not observable.

• Behaviorism primarily focuses on observable behaviors and the stimuli-response mechanisms rather than the cognitive processes.

Cognition & Learning

Learning By Observing

• Vicarious Learning: Learning that occurs through observing consequences of another’s actions (Bandura, 1961).

  • Example: The “Bobo Doll” experiment.

Learning Without Reinforcement

• Explored by Edward Tolman, known for his concept of Cognitive Maps.

Tolman’s Cognitive Maps Experiment

• Different groups explored mazes under varying conditions of food reinforcement to demonstrate latent learning, revealing the unobserved learning potential without immediate reinforcement.

Psychology's Cognitive Revolution

• Marked by a shift towards understanding internal processes and their role in learning, rather than just focusing on observable behaviors.