The effects of tact training on stereotypic vocalizations in children with autism

This study was a systematic extension of Karmali, Greer, Nuzzulo-Gomez, Ross, and Rivera-Valdes (2005) and Ahearn, Clark, MacDonald, and Chung (2007). We investigated the effects of a tact correction procedure on stereotypic vocalizations in 4 children diagnosed with autism who ranged in age from 6 to 16 years. Participants had limited vocal verbal repertoires and were primarily dependent on prompts for the emission of appropriate vocalizations. A multiple-baseline design across participants was used. Data were collected on instances of stereotypic vocalizations and independent tacts during baseline conditions and on instances of stereotypic vocalizations, independent tacts, and echoic-tacts during intervention. Procedural integrity and social validity data were also obtained. The results indicated a decrease in stereotypic vocalizations for 3 of the 4 participants and a slight increase in appropriate vocal verbal behavior (i.e., tacting) for all participants. The study provides support for the use of tact correction procedures to decrease stereotypic vocalizations and increase appropriate vocalizations in children with autism.     

General Outcome Measures for Verbal Operants

A general outcome measure (GOM) can be used to show progress towards a long-term goal. GOMs should sample domains of behavior across ages, be sensitive to change over time, be inexpensive and easy to use, and facilitate decision making. Skinner''s (1957) analysis of verbal behavior may benefit from the development of GOM. To develop GOM, we conducted a review of the literature on mands, tacts, echoics, and intraverbals. The four areas reviewed included (a) an examination of the participant''s response form (i.e., vocal or nonvocal), (b) the type of prompt used, (c) types of materials used, and (d) timing of responses or sessions. Based on the review of the literature, we developed GOM for mands and tacts. This paper attempts to bridge the concept of GOMs with Skinner''s analysis of verbal behavior.     

Using a Lag Reinforcement Schedule to Increase Phonemic Variability in Children With Autism Spectrum Disorders

Shaping functional vocal language is difficult when an individual has not yet acquired an echoic repertoire and does not emit sufficient phonemes (i.e., speech sounds) for shaping. Few studies have evaluated interventions to increase the frequency and breadth of phonemes. The current study extended Esch, Esch, and Love (2009) by evaluating the effects of a Lag 1 reinforcement schedule on vocal variability and limiting the definition of variability to responses that incorporated a novel phoneme. For 2 of the 3 participants, the cumulative number of novel phonemes, the percentage of trials with variability, and the number of different phonemes emitted per session increased during the Lag 1 intervention phase.