Biting attack by rats in response to aversive shock.

Scientists shocked rats through the cage floor. A wooden stick sat inches from each rat’s mouth.

Every shock made the rat bite the stick hard and fast. The team counted bites to see if pain always triggers attack.

Shock started — bite began. Shock stopped — biting stopped. The link was instant and steady.

Biting gave a clean, automatic score of pain-induced aggression. No training needed.

One year earlier the same lab (H et al. 1967) showed that shock also makes rats lunge and flee. The 1968 paper zooms in on biting alone and gives a simpler way to record it.

Adams et al. (1966) found that escape responses only transfer to brain-stimulated attack when the attack includes a cry. Together these studies say: pain can push out different topographies — bite, flee, or vocalize — and each can be measured separately.

Dawson et al. (2000) later showed human aggression can work like escape from interrupted rituals. The rat data remind us that some aggression is not learned; it is a built-in reflex to aversive events.

When you see sudden self-injury or aggression after a demand or loud noise, think reflex first. Remove the aversive event and watch if the behavior stops just as fast as it started. Quick removal can be your first probe before you run a full FA.