Repetition kills warnings

Behaviour Change

In its 2020 regulartion, the U.S. Food and Drug Administration (FDA) required that its various graphic warnings about the risks of cigarette smoking (the increased likelihood of cancer, heart disease, and so forth) be rotated quarterly. Suppose that you see a graphic warning depicting someone in a hospital with lung cancer. The warning might scare you that first time, or even the first five times. But after a while, you might habituate. The depiction might become like background noise. That was exactly the FDA’s concern. It believed that rotation of the various warnings was likely to reduce habituation and capture attention. So the solution was to portray someone in a hospital with lung cancer for a certain period, but then someone with rotting yellow teeth next, and so on.

A warning can remain horrifying and become invisible. Repetition manages this apparently contradictory trick with depressing efficiency.

The first graphic packet interrupts. The fifth is recognised. By the twentieth, the photograph has joined the keys, till receipt and ordinary clutter of purchase. Its medical content has not softened. Its position has become predictable.

Regulation tends to answer fading attention with intensity: larger type, harsher copy, a worse lung, more red. That improves the object while ignoring the viewer’s capacity to learn the pattern. The nervous system is not submitting a complaint about insufficient gore. It is classifying a familiar stimulus and conserving attention.

Rotation restores surprise briefly. Then rotation itself becomes familiar: another grim picture inside the same rectangle. People can recall the message perfectly in an interview and barely inspect it during an ordinary hurried transaction. Understanding and interruption have separated.

This makes one-off research wonderfully flattering. Show the image in a session, ask what it means, record excellent comprehension. The packet’s real habitat—pocket, queue, shop counter, repeated purchase—has been removed from the evidence.

A fresh image enters circulation in April. Early eye-tracking shows longer glances. The next rotation is scheduled before six months of behaviour can be observed. Shops continue placing the packet on the same shelf.