Analyzing Thorndike's Law Of Effect: The Question Of Stimulus-response Bonds.

Malone (1999) re-examines Thorndike’s 1905 idea that rewards glue a stimulus to a response.

The paper pulls together modern lab data where bigger or tastier reinforcers make pigeons and rats keep pecking or pressing longer when extinction hits.

No new experiment was run; the author links old numbers to the century-old bond concept.

The review shows that larger reinforcers produce slower response drop-off when free food or extinction is later given.

This pattern is framed as ‘stronger S-R bonds,’ updating Thorndike with today’s resistance-to-change measures.

Lattal (1974) supplies the key yardstick: response strength equals the exponent of the power function that maps baseline rates to extinction rates. Malone (1999) simply labels that exponent ‘bond strength.’

Dougherty et al. (1994) add the missing piece—sucrose concentration boosts low-rate responding, proving that reinforcer size feeds directly into the same exponent.

Force studies look contradictory at first glance: Anonymous (1995) and Lowe et al. (1995) show that heavier lever presses slow rates, yet Llewellyn et al. (1976) found no loss when force was raised. Malone (1999) resolves the clash by treating force as a cost that weakens the bond, not as a reinforcer that strengthens it, keeping the Thorndikian account intact.

You now have a single old label—‘bond strength’—that unites reinforcer size, response force, and extinction data. When a client’s skill drops fast after you thin reinforcement, think ‘weak bond.’ Boost the reinforcer magnitude or reduce response effort before you fade rewards, then probe again in extinction to check if the bond held.