Week 10 Lecture 1 Video 2 Pavlovian Conditioning

Introduction to Classical Conditioning

• Focus on a specific type of learning studied by researchers: classical conditioning.

Example: Japanese Wax Tree

• The Japanese wax tree (scientific name: Toxicodendron).

  • Some individuals are severely allergic to this plant; exposure can lead to severe rashes or blistering.

  • The name means "poisonous trees," highlighting the severity of its effects on allergic individuals.

Hypothetical Scenario

• Scenario: An allergic person is informed about being touched with a leaf from the wax tree and an identical-looking leaf is used instead.

• Questions posed: What might happen to the allergic person during this scenario?

• Possible reactions include:

  • Rash

  • Blistering

  • Similar allergic responses have been observed.

Connection to Pavlovian Conditioning

• Explanation tied to classical conditioning, also known as Pavlovian conditioning.

• Introduction of Ivan Pavlov:

  • Recognized in psychology but was initially a physiologist and not a psychologist.

  • Planned to become a priest initially, but shifted to studying physiology at St. Petersburg University.

  • Worked on digestion and won a Nobel Prize for Physiology.

Pavlov's Observations with Dogs

• Pavlov observed dogs' behavior concerning food:

  • Dogs salivated when food was presented, which was a reflexive behavior, not learned.

  • Noted salivation occurred with stimuli present at feeding time (e.g., food bowl, person bringing the food).

Neutral Stimulus vs. Conditioned Response

• A neutral stimulus can evoke a reflexive response after being paired with an unconditioned stimulus.

  • Example: The dog salivating at the food bowl even when there's no food.

Experimental Setup

• Methodology:

  • Pavlov paired a neutral stimulus (tone) with an unconditioned stimulus (meat powder) that caused salivation.

  • The experiment involved:

  • Dogs placed in a quiet room, in a harness to limit movement.

  • Repeated pairings of tone and meat powder to measure salivation.

• Results:

  • After repeated pairings, the tone alone could elicit salivation, demonstrating conditioning.

Steps of Classical Conditioning

• Process broken down:

  • Before Conditioning:

  • Unconditioned Stimulus (UCS): Meat powder -> produces salivation (Unconditioned Response - UCR).

  • Neutral Stimulus (NS): Tone -> no response initially.

  • During Conditioning:

  • NS (tone) paired with UCS (meat powder) leading to salivation.

  • After Conditioning:

  • The tone alone becomes a Conditioned Stimulus (CS) -> now elicits salivation (Conditioned Response - CR).

Application to Japanese Wax Tree Example

• Mapping the example to classical conditioning:

  • Before Conditioning:

  • Poison (UCS) -> allergic reaction (UCR).

  • Leaf (NS) -> no reaction initially.

  • During Conditioning:

  • Poison paired with leaf, leading to learned response.

  • After Conditioning:

  • Leaf (now CS) -> elicits the same allergic reaction (now CR).

Impact of Pavlov's Findings

• Pavlov's work ignited interest in classical conditioning in psychological research, extending studies to other animals and humans.

• Emphasis on observable behaviors rather than internal thoughts highlighted by:

  • John Watson, called the father of behavioral psychology.

  • Encouraged examination of measurable behavior.

Case Study: Little Albert Experiment

• Conducted by John Watson and Rosalie Rayner:

  • Demonstrated that classical conditioning could induce fear behaviors in humans.

  • A nine-month-old baby, Little Albert, was conditioned to fear white rats through the addition of a loud sound.

  • Resulted in this fear generalizing to similar stimuli (any white and fluffy objects).

  • Ethical implications: The use of a child raised significant concerns regarding the morality of the experiment.