Reduction of disruptively loud voice volume using a "tok-back" device

This study addressed the disruptively loud voice volume of three adult mentally retarded subjects. A reduction in voice volume was affected through the use of the "tok-back" device, a crescent-shaped device made of lightweight plastic, which when fitted over the face covers the mouth and ears and provides feedback on sounds emitted. In Experiment 1, the tok-back was used with two subjects as an aversive consequence to disruptive screaming. The tok-back was placed over the face after each scream and remained in place until the end of a specified period of quiet. Using a multiple baseline across settings design with each subject, results showed a substantial reduction in screaming following the implementation of the tok-back condition. A multi-element design was used in Experiment 2 to compare the effects of baseline, cueing and tok-back conditions on percent of correct responses, responses given in a soft volume, to simple conversational questions with the third subject. Results showed the tok-back condition to result in a higher percent of correct responding then did either the baseline or cueing conditions.