Emergent intraverbal responses via tact and match-to-sample instruction.

Leigh and team worked with two children with autism. They wanted to see if teaching category tacts and match-to-sample would spark untaught intraverbal answers.

The kids first learned to name pictures by category, like saying "fruit" for an apple. They also matched pictures to the same category. No one asked them to list items in a category yet.

After the tact and match lessons, both children could suddenly answer questions they had never been taught. When asked, "Name some fruit," they listed items like apple and banana.

The intraverbal responses popped out without direct training. The study showed positive emergent learning.

Dass et al. (2018) extends this idea. They also taught category tacts to kids with autism, but used smells instead of pictures. Emergent matching still happened, showing the effect works across senses.

Clements et al. (2021) used a different method called matrix training and got even bigger gains. Their kids learned 8–12 new numeral tacts for every one taught. Leigh’s study did not measure that scale, but both show emergent tacts in autism.

Meier et al. (2012) ran a similar single-case study in the same year. They found that teaching one verbal operant, like a mand or tact, made the other operant emerge. Leigh added match-to-sample and got emergent intraverbals instead of just more tacts or mands.

You can save teaching time by pairing category tacts with match-to-sample. Once the child labels and matches, try probing untaught intraverbal questions like "Tell me some animals." If the answers come, you just gained free skills. If not, you know more direct teaching is needed.