ABA Fundamentals

Experimental analysis of human vocal behavior: applications of speech-recognition technology.

Wirth et al. (2000) · Journal of the experimental analysis of behavior 2000
★ The Verdict

A computer can listen, score, and pay for vocal responses during equivalence training — and the new words still pop out.

✓ Read this if BCBAs running verbal behavior labs or teaching college courses on stimulus equivalence.
✗ Skip if Clinicians who only work on daily living skills with no vocal component.

01Research in Context

01

What this study did

Researchers used speech-recognition software to train adults to say nonsense words.

The computer listened for the right sounds and gave points right away.

Each person got two rounds of training to see if new words would pop out without more teaching.

02

What they found

Most adults started saying new words that belonged to the same group as the trained words.

The speech-recognition setup worked — it caught the words and paid off fast.

Only two short training rounds were enough to see this transfer.

03

How this fits with other research

Pérez‐González et al. (2026) took the same idea further. They used the same equivalence training but pushed adults to solve analogies like 'A is to B as C is to ?' after training.

Cox et al. (2025) also used computers to handle reinforcement, but instead of shaping speech they used AI to guess the next response. Both papers show that pairing tech with ABA can speed things up.

Becraft et al. (2020) gives you the tool to pool many small studies like this one. Their primer shows how to meta-analyze single-case data, so future replications of the speech-recognition method can be combined into one big picture.

04

Why it matters

You can run vocal equivalence drills without sitting next to the learner. The computer scores and pays for correct sounds in real time. This frees you to watch body language or run other kids at the same time. Try it next time you need clean data on emergent verbal relations.

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→ Action — try this Monday

Record three nonsense words into free speech-recognition software and set it to play a ding plus a point when the learner says each word — run a quick probe for emergent relations.

02At a glance

Intervention
stimulus equivalence training
Design
single case other
Sample size
8
Population
neurotypical
Finding
positive

03Original abstract

Recent developments in speech recognition make it feasible to apply the technology to study vocal behavior. The present study illustrates the use of this technology to establish functional stimulus classes. Eight students were taught to say nonsense words in the presence of arbitrarily assigned sets of symbols consistent with three three-member experimenter-defined stimulus classes. Computer-controlled speech-recognition software was used to record, analyze, and differentially reinforce vocal responses. When the stimulus classes were established, students were taught to say a new nonsense word in the presence of one member of each stimulus class. Transfer of function was tested subsequently to determine if the novel stimulus names transferred to the remaining stimulus class members. Most subjects required two iterations of the training and testing procedures before transfer occurred. The data illustrate the usefulness of recording vocal behavior during stimulus control procedures and demonstrate the use of speech-recognition technology. The paper also describes the current state of speech-recognition technology and suggests several other areas of research that might benefit from using vocal behavior as its primary datum.

Journal of the experimental analysis of behavior, 2000 · doi:10.1901/jeab.2000.74-363