a method and apparatus for conducting an operant conditioning paradigm designed to maintain the absence of vocal behavior , by a subject infant , which is equal to or above a predetermined audible level , thereby decreasing the probability of abusive behavior directed toward the subject infant by a parent or care provider . a specific schedule of reinforcement is utilized to maximize the effects of positive reinforcement , with the operation of the appropriate mode of the schedule of reinforcement being a function of the continuously monitored vocal behavior of the subject infant . a maintenance mode of said schedule of reinforcement includes the intermittent presentation of positive reinforcers , with the operation of said mode continuing indefinitely and independent of subject infant behavior until and unless the predetermined audible level is exceeded . a reacquisition mode of said schedule of reinforcement includes the contingent presentation of positive reinforcers , with the presentation of said positive reinforcers being contingent upon the cessation of vocal behavior which exceeds the predetermined audible level . a novel stimulus presentation mode is utilized to elicit a pause in vocal behavior which has exceeded the predetermined audible level for a predetermined period of time . an apparatus functioning per the present method may be enclosed in a unitary package adapted for attachment to a crib , playpen , or other appropriate child care device .