AE Files

OXFORD UNIVERSITY PRESSTRANSLATED BY G. V. ANREPConditionedReflexesI. P. PAVLOV1927
Named:
1927, Ivan Pavlov
Modeled:
1958, Evgeny Sokolov, Moscow State University
Trigger:
Any new or changed stimulus

The orienting reflex is the automatic turn toward anything new. A sound, a movement or a change in light pulls the head and eyes toward it before any decision is made. Pavlov called it the what-is-it reflex. Heart rate drops, the pupils widen and whatever the animal was doing stops.

The reflex fades when a stimulus repeats and returns when the stimulus changes. Sokolov mapped this in Moscow in the 1950s. Screen media runs on the second half of that finding. A cut, a zoom, a badge and a vibration are all changes, so each one fires the reflex again. The viewer keeps looking because the reflex keeps getting restarted.

FIG. 1 THE TURNNEW STIMULUSHEAD AND EYESHEART RATE DROPSPUPILS WIDENCURRENT ACTION STOPS

The What-Is-It Reflex (1927)

When Pavlov walked in to watch a demonstration, the dog turned to look at him and sniff, and the newly trained response vanished. Pavlov recorded the interruption as a reflex of its own.

Habituation (1958)

Sokolov played the same tone again and again. The response shrank with each repetition and then disappeared. One change in pitch brought it back. The brain keeps a model of what it expects and reacts to the difference.

FIG. 2 RESPONSE TO A REPEATED TONE123456789101112PITCH CHANGESTRIALRESPONSE
FIG. 3 EDITS AGAINST BRAIN ACTIVITYCUTCUTCUTALPHA ACTIVITYTHE RESPONSE FOLLOWS EACH EDIT

The Cut (1985)

Byron Reeves and colleagues recorded brain activity from people watching television. Scene changes and movement on screen each shifted the alpha rhythm, a marker of the orienting response. Editing pace sets how often the reflex fires.

Variable Reward

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