Comparing stimulus preference and response force in a conjugate preparation: A replication with auditory stimulation

Cook et al. (2024) asked people to squeeze a hand dynamometer while music played.

Harder squeezes made the song louder in real time.

The team recorded which songs each person said they liked best, then checked if the squeeze force matched those words.

For about two-thirds of the group, the songs they said they loved were the same songs they squeezed hardest for.

Force tracked preference without any extra rewards like food or money.

CHUNG (1965) first showed that once a response takes too much force, rate drops. Cook flips that rule: force becomes the signal, not the barrier.

Stancliffe et al. (2007) saw mice keep pressing even when the lever got heavy, proving force itself is not a punisher. Cook’s humans did the same—willingly working harder for better tunes.

Anonymous (1995) and Lowe et al. (1995) both found higher force requirements slow rats’ fixed-ratio responding. The new study looks like a contradiction, but the difference is purpose. The rat studies used force as a cost; Cook used force as a ruler to measure value. When effort is the currency, not the price, more force simply means “I like this more.”

You now have a quick, objective way to rank auditory reinforcers. Let a client squeeze, watch the force trace, and the highest peak tells you which song to place on a reinforcement schedule. No interviews, no tokens, just data in seconds.