Pavlov: The Conditioned Reflex

Five experiments into how a reflex is learned

A course on the thought of Ivan Pavlov.

Psychology

What you will learn

Name the four parts of the mechanism — unconditioned stimulus and response, conditioned stimulus and response — and the pairing that creates a conditioned reflex.
See conditioning as a measurable, reproducible process built over trials (acquisition), not a metaphor.
Define extinction — the fading of a conditioned response when the signal is given repeatedly without reinforcement — and distinguish it from forgetting.
Grasp spontaneous recovery, and see why it shows extinction suppresses the conditioned bond rather than erasing it.
Define stimulus generalization — the spread of a conditioned response to stimuli resembling the trained one, less as they differ.
Define discrimination as the learned narrowing of the response to only the reinforced signal, achieved by reinforcing one and extinguishing the others.
State the principle of signalisation — that the cerebral hemispheres let a great number of otherwise-unimportant stimuli signal the few agencies of real importance to the organism.
See the conditioned reflex not as a laboratory trick but as the atom of how an animal anticipates and meets its world.

The Salivating Dog — The accidental observation in a digestion study that became the first science of learning — and how a neutral signal comes to trigger a reflex.
Making and Breaking a Reflex — How a conditioned reflex fades when the signal stops being kept — and why its return after rest proves the bond was hidden, not destroyed.
Telling Signals Apart — Why a conditioned response spreads to signals resembling the trained one — and how the animal is taught to draw a fine line between them.
The World as Signals — my central claim — the conditioned reflex is the elementary way an animal's brain lets distant, unimportant signs stand in for the vital things they precede — and the objective method that let this…
Conditioning in Your Own Life — The laws of the salivating dog, read back into human craving, fear, and its treatment — and where the Foundations end and the deeper tiers begin.

Conditioned Reflexes (1927) — my synthesis, translated by Anrep — twenty-three lectures turning salivary conditioning into a general account of the brain's higher activity.
Lectures on Conditioned Reflexes (1928) — the Gantt translation of my addresses and papers on the conditioned reflex and its laws.
The Work of the Digestive Glands (1902) — the digestion research that won the 1904 Nobel Prize — and where the conditioned reflex was first glimpsed as a nuisance in the data.

conditioned stimulus, extinction, signalisation

Part of the Simposeum course library.