Animal psychophysics: improvements in the tracking method.

Harrison et al. (1975) worked with rats in a tracking task. The rats pressed a lever to change the loudness of a tone. If they pressed at the wrong time, the next tone got louder. Near the quiet threshold, the rats only had to lick once to earn water. Everywhere else they had to lick many times.

The goal was to keep the rats locked on the faint edge of hearing and cut goof-off lever presses.

The new rules worked. The animals stayed right at threshold and rarely pressed when no tone was on.

Stable thresholds and clean data came from two simple twists: penalize errors with a tougher next trial, and keep reward effort equal across loud and soft sounds.

MOORHEARSKELLEHER et al. (1964) showed that inserting darkness during a delay boosts response rate. M et al. echo this idea: add a clear consequence (brighter tone) and performance tightens.

Wolchik et al. (1982) warned that paying for errors can blur discrimination. M et al. dodge the trap by making the penalty a tougher stimulus, not a food reward. Same concern, different fix.

Schwartz et al. (1971) gave pigeons an extra pecking key to bridge long waits. M et al. thin the licking work near threshold for the same reason: give the animal a helper that evens out reinforcement density. Both tricks raise accuracy without touching the main contingency.

If you run auditory discrimination with clients, steal the two moves. First, program an error to raise the next stimulus value; the learner feels the mistake immediately. Second, keep the response cost for reinforcement the same across easy and hard trials so the easy ones don’t become mini-parties. Together you get cleaner thresholds and fewer off-task responses in any sensory assessment or teaching program.