PSYC 104 Chapter 5- Learning

1. Learning Overview

• Definition: Learning is a relatively permanent change in an organism’s behavior due to experience. This contrasts with innate behaviors, which are genetically programmed (e.g., salmon migration).

• Associative Learning: Learning that involves associating two events.

  • Classical Conditioning: Learning to associate two stimuli (e.g., a tone and food).

  • Operant Conditioning: Learning to associate a behavior with its consequences (e.g., pressing a lever for food).

Basic Forms of Learning

• Classical Conditioning: Learning to associate two stimuli (Pavlov's dog experiment).

• Operant Conditioning: Learning the consequences of behavior (Skinner’s experiments).

• Observational Learning: Learning by watching others (Bandura’s Bobo Doll experiment).

2. Classical Conditioning (Pavlov)

• Ivan Pavlov: A Russian physiologist who discovered classical conditioning through experiments with dogs.

• Key Concepts:

  • Unconditioned Stimulus (US): A stimulus that naturally triggers a response (e.g., food).

  • Unconditioned Response (UR): The natural response to the unconditioned stimulus (e.g., salivation).

  • Neutral Stimulus (NS): A stimulus that initially produces no specific response (e.g., a tone).

  • Conditioned Stimulus (CS): Previously the neutral stimulus, now triggers a conditioned response after association with the US.

  • Conditioned Response (CR): A learned response to the conditioned stimulus (e.g., salivation to the tone).

Classical Conditioning Process

• Acquisition: The initial stage when the neutral stimulus becomes associated with the unconditioned stimulus. For conditioning to be effective, the neutral stimulus should precede the unconditioned stimulus by about half a second.

• Extinction: When the conditioned stimulus is presented without the unconditioned stimulus, the conditioned response gradually weakens and eventually disappears.

• Spontaneous Recovery: The reappearance of the conditioned response after a period of extinction, although it may be weaker.

• Stimulus Generalization: The tendency to respond to stimuli similar to the conditioned stimulus.

  • Example: Pavlov’s dogs salivated when vibrations were applied to different parts of their bodies, not just the thigh.

• Stimulus Discrimination: The learned ability to distinguish between the conditioned stimulus and other similar stimuli that do not signal the unconditioned stimulus.

Biological Predispositions

• Some associations are easier to learn due to biological factors. For example, certain tastes are more easily associated with illness (taste aversion), as shown in John Garcia’s experiments.

3. Applications of Classical Conditioning

• Drug Addiction: Cues (people, places) associated with drug use can trigger cravings.

• Immune System: Through classical conditioning, a taste associated with a drug that influences the immune response can trigger the same response when only the taste is presented.

• Advertising: John Watson applied classical conditioning to create emotional responses in advertising, e.g., Maxwell House’s "coffee break."

4. Operant Conditioning (Skinner)

• Operant Conditioning: Learning where behavior is influenced by its consequences (rewards or punishments).

Thorndike’s Law of Effect

• Law of Effect: Behaviors followed by favorable consequences are more likely to be repeated, and behaviors followed by unfavorable consequences are less likely to be repeated.

Skinner’s Experiments

• Operant Chamber (Skinner Box): An enclosure where animals can press a lever or peck a key to receive a reward (e.g., food), which helps study behavior patterns.

• Shaping: A process in operant conditioning in which reinforcers guide behavior toward a desired target behavior through successive approximations.

Reinforcement

• Reinforcer: Any event that strengthens the behavior it follows.

  • Primary Reinforcer: Innately reinforcing (e.g., food, water).

  • Conditioned (Secondary) Reinforcer: Gains its power through association with a primary reinforcer (e.g., money, praise).

• Immediate vs. Delayed Reinforcers:

  • Immediate Reinforcer: Occurs instantly after a behavior (e.g., giving a treat to a pet right after a trick).

  • Delayed Reinforcer: Delayed gratification, such as receiving a paycheck at the end of the month.

Punishment

• Definition: Any event that decreases the behavior it follows.

  • Positive Punishment: Administering an aversive stimulus (e.g., spanking).

  • Negative Punishment: Withdrawing a desirable stimulus (e.g., taking away privileges).

• Negative Effects of Punishment:

  • Results in unwanted fears.

  • Justifies pain to others.

  • May lead to aggression or unwanted behaviors in the absence of punishment.

5. Observational Learning (Bandura)

• Definition: Learning by observing and imitating others.

• Bandura’s Bobo Doll Experiment: Showed that children learn aggression by watching others being rewarded or punished for aggressive behavior.

• Mirror Neurons: Neurons in the frontal lobe that activate when we observe others performing an action, helping us imitate and empathize.

6. Limits of Conditioning

• Biological Constraints: Some associations are easier to learn because they are more biologically relevant. For instance, taste aversion is easier to condition than visual or auditory cues.

• Cognitive Processes:

  • Animals learn to predict events (cognitive maps), as shown in studies where rats develop mental representations of mazes even without rewards.

Summary of Key Learning Theories

• Classical Conditioning: Learning associations between stimuli (involuntary responses).

• Operant Conditioning: Learning associations between behaviors and their consequences (voluntary behaviors).

• Observational Learning: Learning by watching and imitating others’ behaviors.