ABA Fundamentals

A review of reinforcement control procedures.

Thompson et al. (2005) · Journal of applied behavior analysis 2005
★ The Verdict

Copying a baby’s sounds right away reliably raises imitative babbles, yet total talking may stay flat—check each child.

✓ Read this if BCBAs teaching early vocal skills to infants or toddlers in home or clinic programs.
✗ Skip if Clinicians working only with fluent speakers or with adults.

01Research in Context

01

What this study did

Reid et al. (2005) watched how caregivers shape baby talk.

Each time an infant babbled, the adult copied the sound right away.

They flipped this on and off to see if babies babbled more when adults imitated them.

02

What they found

Every baby started copying the adult sounds more when the adult first copied them.

Total babbling did not always rise; some babies talked less even while copying more.

The procedure works for imitation, but you cannot assume it will boost all vocal output.

03

How this fits with other research

Jorgenson et al. (2020) got the same mixed picture with preschoolers with autism.

They swapped the dog for the imitating adult and still saw child-to-child differences.

Spjut Janson et al. (2022) extended the idea: three months of adult copying toddlers with ASD later helped eye-gaze joint attention once ABA started.

Liberman et al. (1973) showed the root idea decades earlier: reinforcing an imitative response can replace odd gestures in older children with ID.

04

Why it matters

If you want more imitative sounds, immediate copying is a quick win.

Track each child’s total vocal output before you claim the intervention “increased language.”

Probe first, then decide whether to keep, change, or pair the tactic with something stronger.

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Count both imitative and total vocalizations during five-minute baseline, then run ten minutes of contingent imitation and compare the two numbers.

02At a glance

Intervention
differential reinforcement
Design
alternating treatments
Sample size
3
Population
neurotypical
Finding
mixed

03Original abstract

The present study replicated and extended the Pelaez et al. (Journal of Applied Behavior Analysis 44:33-40, 2011) study, which examined the reinforcing effects of mothers' contingent imitation of their infants' vocalizations. Three infants aged 7-12 months who could vocalize sounds but not words participated with two caregivers for each infant (i.e., triads). During the intervention phase, the caregivers were asked to immediately imitate all vocalizations emitted by the child for a 3-min period. During the yoked control phase, the caregivers listened to an audio recording from the preceding condition and provided vocalizations non-contingently on the infants' responses. The procedures yielded different results across participants; one infant emitted a higher frequency of vocalizations during the contingent imitation phases over the control phases, and the other two infants showed higher rates of responding during the control phases. However, all infants emitted more imitative return vocalizations during contingent reinforcement conditions compared with the yoked control condition.

Journal of applied behavior analysis, 2005 · doi:10.1901/jaba.2005.176-03