Operant reinforcement of an autonomic response: two studies.

Gibbon (1967) asked a simple question: can we reward a sweat response? The team wired adults to a meter that tracks tiny skin-moisture changes called GSR. When the meter jumped above each person’s own average, the room lamp brightened for two seconds. That light flash was the reinforcer.

Two separate experiments ran. In both, half the people got the light only after big GSR spikes. The other half saw the same light on a fixed schedule no matter what their skin did. Each session lasted one hour.

The paid-off group produced more sweat spikes than the yoked controls. The difference showed up in the first ten minutes and held steady. The effect repeated in the second study with new volunteers.

Size mattered: bigger light flashes pushed GSR even higher. The skin response was tiny, but it moved exactly like a bar press or a key peck.

Thrailkill et al. (2018) seems to disagree. They show that rich reinforcement during training makes behavior return later after you stop paying. Gibbon (1967) shows rich reinforcement helps right away. The gap is timing. J looks at the gain during acquisition; Thrailkill looks at relapse after extinction. Same coin, opposite sides.

LeBlanc et al. (2003) extend the story. They prove that higher pay rates not only lift response count but also make the behavior tougher to disrupt. J showed the lift; A et al. show the shield.

Kuroda et al. (2018) add a twist: the correlation between response and reward, not just the timing, drives the learning. J used a tight one-to-one correlation, so the GSR result fits neatly with their rule.

If reinforcement can grow a sweat drop, it can grow anything. When you see a client’s heart-rate or skin-tone change, ask what payoff might be fueling it. Before you treat a “physiological symptom,” test an extinction or differential-reinforcement plan. You might be shaping the very thing you are trying to measure.