Effects of a pre-aversive stimulus upon oddity performance in monkeys.

Scientists gave monkeys an oddity task. The animals had to pick the picture that did not match.

While the monkeys worked, a tone sounded. The tone meant a mild shock was coming. The team wanted to know if the warning would hurt the monkeys’ choices.

The monkeys pressed the button less when the tone played. Their accuracy stayed the same.

Even when shock strength went up, the monkeys still picked the right picture.

Snapper et al. (1969) saw the opposite. Rats lost timing skill when the same tone-shock pair played. The jobs differ: monkeys matched pictures, rats judged time.

Blackman (1970) later showed rats also lost timing control with a pre-shock cue. That study builds on the 1968 work but finds a weaker spot in timing tasks.

Garcia et al. (1973) found the cue broke a counting chain in rats. All three later papers show some loss of control, yet the 1968 monkeys kept perfect accuracy.

The data tell you that aversive events can slow behavior without hurting accuracy. If a learner stalls during hard tasks, check whether fear cues are present. You might keep the skill intact by adding extra prompts or reinforcement while you remove or fade the scary signal.