ABA Exam CoachVerbal operants: mand, tact, echoic, intraverbal
The word "ball" can be a mand, a tact, an echoic or an intraverbal. That's the whole difficulty with this topic, and the whole key to it. Skinner classified verbal behavior by its controlling variables, not by the words a person says. Sautter and LeBlanc (2006) summarise it the same way: each verbal operant is defined by its functional relation to antecedents and consequences, not by its form or meaning.
The BACB's 6th edition outline has a task for identifying and distinguishing among verbal operants (B.19) and a separate task on multiple control (B.20).
Two questions decide it
For any verbal response, ask:
- What evoked it? A motivating operation, a nonverbal thing in the environment, or someone else's verbal behavior?
- What followed it? The specific thing the person asked for, or general social reinforcement such as "That's right!"
If the antecedent is verbal, ask a third question: does the response match the stimulus? Two features matter:
- Point-to-point correspondence: each part of the stimulus controls a matching part of the response.
- Formal similarity: the stimulus and the response are in the same sense mode and look or sound alike.
The operants in one table
| Operant | What evokes it | Correspondence with the stimulus | What usually reinforces it | Original example |
|---|---|---|---|---|
| Mand | An MO (deprivation, an aversive stimulus) | n/a | The specific item or event named | A thirsty child says "juice" and gets juice |
| Tact | A nonverbal stimulus (an object, event or property) | n/a | Generalized conditioned reinforcement | A child sees a fire engine and says "fire engine!", and Dad says "Yes, it is!" |
| Echoic | A spoken verbal stimulus | Point-to-point and formal similarity | Generalized conditioned reinforcement | The therapist says "apple" and the learner says "apple" |
| Intraverbal | A verbal stimulus | No point-to-point correspondence | Generalized conditioned reinforcement | Someone asks "What do cows say?" and the learner says "moo" |
| Textual | Written words | Point-to-point, but no formal similarity (seen → said) | Generalized conditioned reinforcement | Reading the word "exit" aloud from a sign |
| Transcription | Spoken words | Point-to-point, but no formal similarity (heard → written) | Generalized conditioned reinforcement | Writing down a phone number as it's read out |
Autoclitics sit on top of these. They are verbal responses that modify how the listener reacts to the speaker's other verbal behavior, such as "I think it's raining" or "I definitely saw it".
Mand vs tact: the most tested pair
Both can involve the same word, so look past the word.
- Mand: the learner hasn't had a snack all afternoon, sees nothing, and says "crackers". The MO evokes it, and only crackers will reinforce it.
- Tact: the learner has just eaten, sees a box of crackers on the table, and says "crackers". An adult says "Yes, crackers". The box evokes it, and praise reinforces it.
A quick check: would handing them the item satisfy the response? If giving the crackers is the reinforcer that maintains the response, it's a mand. If they'd be just as content with "yes, those are crackers", it's a tact.
Non-example: a learner points to crackers when an adult says "show me the crackers". That's listener behavior (often called receptive identification), not a tact. Nothing was said by the learner.
Echoic vs intraverbal
Both are evoked by someone else's speech. The difference is whether the response copies it.
- "Say bubbles" → "bubbles" is an echoic. The sounds match.
- "You blow..." → "bubbles" is an intraverbal. The response doesn't match the words that evoked it.
- "Ready, set..." → "go" is an intraverbal, even though it's short and automatic.
If an exam item describes a fill-in-the-blank, a song completion or an answer to a question, think intraverbal.
Common traps
- Deciding from the word. "Water" tells you nothing. Find the MO, the nonverbal stimulus or the verbal stimulus.
- Calling every naming response a tact. A learner who has been sitting in the heat sees a fan and says "fan!", then stops talking once someone switches it on. The fan is in view, but the heat (an MO) and the specific consequence (the fan running) make it a mand.
- Forgetting textual behavior has no formal similarity. Print and speech are different sense modes, so reading aloud isn't echoic.
- Treating answers to questions as tacts. "What color is the sky?" with no sky in view evokes an intraverbal. With the sky in view, the response may be under multiple control: the question and the sky together.
- Ignoring multiple control. Michael, Palmer and Sundberg (2011) argue that multiple control is the rule rather than the exception. A single response often has more than one source. Exam items about B.20 ask you to spot those extra sources.
Practise it
For each verbal response in a scenario, write three words before you choose an answer: MO, thing or words. Then check the consequence. With practice, mand and tact questions become quick wins.
The lesson on B.19: telling the verbal operants apart walks through each operant with examples, and B.20: multiple control covers the follow-up. To see how you're doing across B. Concepts and Principles, take the free diagnostic.
FAQ
What is the difference between a mand and a tact? A mand is evoked by a motivating operation and reinforced by the specific thing it specifies. A tact is evoked by a nonverbal stimulus and maintained by generalized conditioned reinforcement such as praise.
Is answering a question an intraverbal? Usually, yes, when the question is the main controlling stimulus and the answer doesn't copy it. If the thing being asked about is also present, the response may be under multiple control.
What's the difference between echoic and textual? Both have point-to-point correspondence. An echoic copies spoken words with spoken words, so it also has formal similarity. Textual behavior turns written words into speech, so it doesn't.
Is pointing to a picture a tact? No. Pointing on request is listener behavior. A tact is the learner's own verbal response to a nonverbal stimulus.
Sources
- BACB, BCBA Test Content Outline (6th ed.): https://www.bacb.com/wp-content/bcba-outline-6thEd (tasks B.19 and B.20)
- Sautter, R. A., & LeBlanc, L. A. (2006). Empirical applications of Skinner's analysis of verbal behavior with humans. The Analysis of Verbal Behavior, 22, 35–48: https://pmc.ncbi.nlm.nih.gov/articles/PMC2774593/ (verbal operants defined by functional relations rather than form or meaning)
- Michael, J., Palmer, D. C., & Sundberg, M. L. (2011). The multiple control of verbal behavior. The Analysis of Verbal Behavior, 27, 3–22: https://pmc.ncbi.nlm.nih.gov/articles/PMC3139558/ (multiple control as the rule rather than the exception)