Some children with autism spectrum disorder do not imitate vocalizations made by others. This skill is known as echoics. Some children will mand (request items they want) but have difficulty developing echoics. Other children may babble with spontaneous sounds or word approximations but struggle with echoics.

To increase vocalizations, Carbone (2012, PPT) reports that the following interventions have been found effective:

1. Reinforcing all Vocalizations
2. Stimulus-Stimulus Pairing (Automatic Reinforcement)
3. Echoic Training
4. Alternative Communication Methods- Manual Sign Language and PECS
5. PECS and Manual Sign Mand Training with Time Delay and Differential Reinforcement Procedures
6. Shaping Vocal Productions. (Phonetic Transcription)
Koegel, O’Dell and Dunlap (1998) demonstrated that reinforcement of all attempts to speak strengthen the rate and
accuracy of speech productions in children with autism with severe deficits of vocal production. This suggests that reinforcing all spontaneous vocalizations that a child makes is likely to increase frequency of vocalizations.
Additionally, stimulus-stimulus pairing procedures may increase spontaneous vocalization frequency and variety. Stimulus-stimulus pairing refers to repeatedly presenting a vocalization target with a stimulus. The child eventually learns that the sound or word is associated with the stimulus. This is particularly effective when the speech sound is paired with a reinforcing stimulus.
For echoic training, Carbone suggests selecting targets to teach based on the following considerations:
1. Developmentally easy sounds
2. High frequency sounds the learner produces during free operant procedures
3. Sounds and words associated with reinforcers and for reinforcers for which the child mands
Carbone suggests the following procedure for echoic training:
1. Once echoic targets are selected, list on the probe data sheet echoic responses that will be taught first.
2. Begin the teaching procedure by having strong reinforcement available and visible to the learner to establish motivation for correct responding.
3. Present the echoic.
4. If the learner reaches parity, reinforce immediately.
5. If the learner does not reach parity, re-present the word 2-3 more times (based upon the learner).
6. At any point the learner reaches parity or a better response occurs, reinforce.
7. If the learner does not reach parity or give a better response following 2-3 echoic trials, drop to an easier echoic or motor imitation response and differentially reinforce.
See the Carbone powerpoint for more information about vocalization training in children with autism.
image credit: via Fotalia