UCLA+PS+147+2025+Lecture+4

Ivan Pavlov: Background and Contributions

  • Name: Ivan Pavlov (1849-1936)
  • Nobel Prize: Awarded in 1904
    • Recognized for his work on the physiology of digestion
    • Transformed and enlarged knowledge on vital aspects of digestion

Laboratory of Genetics of Higher Nervous Activity

  • Location: Koltushi, Russia
    • Focus on observation and its significance in understanding higher nervous activity.

Experimental Setup in Pavlov's Research

  • Basic Arrangement:
    • Includes a tube for collecting saliva from the subject's mouth.
    • An apparatus to record the amount of saliva produced.
    • A harness was used to restrict the movement of the subject to ensure consistent observations.

Conditioning Paradigms

Analysis of Pavlov's Basic Conditioning Paradigm

  • Definitions:
    • Unconditioned Stimulus (UCS): A stimulus that naturally and automatically triggers a response without any conditioning.
    • Unconditioned Response (UCR): The unlearned, naturally occurring response to the unconditioned stimulus.
    • Neutral Stimulus (NS): A stimulus that initially elicits no response until it is paired with the unconditioned stimulus.
    • Conditioned Stimulus (CS): A previously neutral stimulus that, after becoming associated with the unconditioned stimulus, eventually comes to trigger a conditioned response.
    • Conditioned Response (CR): The learned response to a previously neutral stimulus.

Phase 1: Before Conditioning

  • Stimuli and Responses:
    • Neutral Stimulus (NS): Tone
    • Response: No response is elicited by the neutral stimulus.
    • Unconditioned Stimulus (UCS): Meat powder
    • Unconditioned Response (UCR): Salivation

Phase 2: During Conditioning

  • Process:
    • The neutral stimulus (tone) is paired with the unconditioned stimulus (meat powder) to elicit a response (salivation).

Phase 3: After Conditioning

  • Outcome:
    • The neutral stimulus (tone) alone now elicits a response (salivation) without the presence of the unconditioned stimulus, transforming it into a conditioned stimulus (CS).
    • Summary of the Process:
    • Originally neutral stimulus (NS) becomes a conditioned stimulus (CS), resulting in a conditioned response (CR) of salivation.