Concurrent schedules: Quantifying the aversiveness of noise.
Aversive noise produces measurable, quantifiable response bias that can be captured with a tweaked matching equation.
01Research in Context
What this study did
The team worked with hens in a lab. Two keys sat side by side on the wall.
Pecking either key paid grain on variable-interval schedules. One key also turned on loud noise for a moment.
The researchers watched which key each hen preferred. They plugged the counts into a tweaked matching equation to turn noise into a number.
What they found
Every hen moved most pecks to the quiet key. The math showed a clear bias away from noise.
A simple change to the matching law captured the size of that bias.
How this fits with other research
Malouff et al. (1985) used the same hen setup but no noise. They showed that time and response rates line up only when you drop off-task time. The 1996 paper keeps that rule and adds a noise cost.
Witts et al. (2024) tried new lab tools—progressive-ratio and observing tests—to rank how bad stimuli feel for people. Both teams want the same thing: a number for aversiveness. Different species, same goal.
Quinsey (1972) shocked rats for licking. Shock cut behavior hard. Noise in 1996 also cut behavior, but the matching law let the authors measure the cut in fine units instead of just up-or-down.
Why it matters
You now have a ready ruler. If a client avoids a room, task, or voice, set up two easy jobs with different rates of that stimulus. Count responses, drop off-task time, and plug the numbers into the bias term. You will get a quick score that tells you how aversive the stimulus is for that person. Use the score to pick goals, adjust reinforcement, or show progress to caregivers.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Run a five-minute concurrent choice probe: offer two easy tasks, one with the aversive sound and one without, count responses, and see which side the client picks.
02At a glance
03Original abstract
Four hens worked under independent multiple concurrent variable-interval schedules with an overlaid aversive stimulus (sound of hens in a poultry shed at 100dBA) activated by the first peck on a key. The sound remained on until a response was made on the other key. The key that activated the sound in each component was varied over a series of conditions. When the sound was activated by the left (or right) key in one component, it was activated by the right (or left) key in the other component. Bias was examined under a range of different variable-interval schedules, and the applicability of the generalized matching law was examined. It was found that the hens' behavior was biased away from the sound independently of the schedule in effect and that this bias could be quantified using a modified version of the generalized matching law. Behavior during the changeover delays was not affected by the presence of the noise or by changes in reinforcement rate, even though the total response measures were. Insensitivity shown during the delay suggests that behavior after the changeover delay may be more appropriate as a measure of preference (or aversiveness) of stimuli than are overall behavior measures.
Journal of the experimental analysis of behavior, 1996 · doi:10.1901/jeab.1996.65-37