By Matt Harrington, BCBA · Behaviorist Book Club · April 2026 · 12 min read

Teaching Intraverbal Behavior: Building Conversational and Academic Language in ABA

Overview & Clinical Significance

Intraverbal behavior is one of Skinner's primary verbal operants, defined as a verbal response that is controlled by a prior verbal stimulus — another person's speech or the learner's own prior verbalizations — without a point-to-point correspondence between the controlling stimulus and the response. When a child fills in the blank 'Twinkle, twinkle, little ___,' answers 'What sound does a dog make?' with 'Woof,' or responds to 'What do you do when you're hungry?' with 'Eat,' they are demonstrating intraverbal behavior.

For learners with autism spectrum disorder and related language delays, intraverbal deficits are among the most clinically significant and practically impactful aspects of their language profile. Intraverbal skills are the foundation of conversational exchange, academic participation, and social communication. A learner who can tact visible objects and mand for preferred items but cannot answer simple questions, complete fill-in sentences, or engage in back-and-forth conversation has a language profile that will limit educational integration, peer relationships, and independence despite apparent verbal ability.

From a behavior analytic standpoint, intraverbal behavior is distinct from tact behavior (naming visible objects) and mand behavior (requesting) and requires separate, systematic instruction. Many practitioners make the error of assuming that learners who have mastered tacts and mands will naturally develop intraverbal skills — that conversational language will emerge from strong labeling repertoires. The evidence does not support this assumption. Intraverbals require direct instruction using the same systematic teaching procedures applied to other verbal operants.

For RBTs and ABATs who implement intraverbal training programs, understanding the verbal operant distinction — and specifically the difference between intraverbal responses and tact responses — is prerequisite to correct implementation. A learner responding to 'What color is the sky?' by looking out the window and naming what they see is tacting, not producing an intraverbal. The instruction that produces true intraverbals requires the verbal stimulus alone to control the response, without support from visible environmental stimuli.

Background & Context

Skinner's 1957 analysis of verbal behavior introduced the intraverbal as a distinct operant class, but its clinical application received relatively limited attention until the verbal behavior movement in ABA gained momentum in the 1990s. Sundberg and Partington's work on teaching language to children and the development of the VB-MAPP assessment tool brought intraverbal assessment and programming to the forefront of ABA practice.

The VB-MAPP includes intraverbal skills across its Milestones Assessment at multiple developmental levels, from early fill-in responses ('Peek-a-___') through simple question answering and category responses to complex multi-turn conversational exchanges. This developmental progression guides the sequencing of intraverbal instruction in practice: earlier, more rudimentary intraverbal forms are targeted before complex conversational exchanges that require extended intraverbal chains.

The stimulus control challenges in intraverbal teaching are more complex than in mand or tact teaching. In mand training, the motivating operation provides clear evocative control. In tact training, the present stimulus provides a clear discriminative stimulus for the response. In intraverbal training, the controlling stimulus is a prior verbal event, which is brief, transient, and must compete with a range of other environmental stimuli for control over the response. This makes intraverbal errors highly informative diagnostically: when a learner responds to an intraverbal question with a tact of a visible stimulus, the clinician learns that the verbal SD is not exerting adequate control.

Research in JABA has documented the effectiveness of multiple instructional procedures for establishing intraverbal behavior, including errorless learning with prompt fading, transfer of control from tact to intraverbal, multiple-exemplar training, and differential reinforcement of correct verbal responses. The field continues to investigate the conditions under which intraverbal behavior generalizes beyond the specific trained exemplars — an area of ongoing clinical importance because intraverbal skills must ultimately be flexible and generative, not rigidly stimulus-specific.

For staff training purposes, intraverbal instruction is challenging to implement correctly because errors in stimulus control are easy to make and difficult to detect. A supervisor who hears a learner producing correct responses during an intraverbal program may not realize that the learner is tacting a visible prompt card rather than responding to the verbal SD alone. Direct observation with systematic error analysis is essential for maintaining intraverbal program integrity.

Clinical Implications

Establishing intraverbal behavior in the repertoire of learners with significant language delays typically requires a transfer-of-control sequence. For many learners, the progression begins with tact training — establishing a verbal response under control of a visible stimulus — and then transfers that response to intraverbal control by presenting the verbal stimulus and systematically fading the visual stimulus. This tact-to-intraverbal transfer is documented in the applied literature and represents a clinically reliable pathway for learners who have tact repertoires but no corresponding intraverbal behavior.

Fill-in tasks are often the entry point for early intraverbal training because they provide a partially complete verbal stimulus that limits the response options and reduces the complexity of the intraverbal demand. 'You eat with a ___' or 'Ready, set, ___' are examples of fill-in tasks that require minimal intraverbal control to produce correct responses. As fill-in mastery is established, the verbal stimulus can be modified toward full questions, reducing the phonological cue provided by the sentence stem.

Category intraverbals — responding to 'Name some animals' or 'What do you do at school?' — require a different skill than simple question answering. They involve generating multiple responses to a single verbal stimulus and are among the most generative and flexible intraverbal skills. Teaching category intraverbals begins with single-item responses and systematically builds toward multi-item fluent responding. Multiple-exemplar training — teaching the same category response across multiple antecedent forms — supports the emergence of generative category behavior.

Conversational intraverbals — the back-and-forth verbal exchanges that constitute everyday social interaction — are among the highest-priority clinical goals for learners with autism. These exchanges require not only that the learner respond to the verbal stimulus but that they produce responses that are topically coherent, socially appropriate, and connected to the conversational context. Naturalistic teaching procedures, including incidental teaching and natural environment training, are particularly well-suited to building conversational intraverbals because they allow instruction to occur in the actual conversational contexts where the skills will be used.

Error patterns in intraverbal programs provide important diagnostic information. Consistent echoing of the question stem may indicate echoic control of the response rather than intraverbal control. Consistent pointing to visible stimuli before responding indicates that tact control is competing with verbal control. Repeating the same limited set of responses regardless of the question indicates limited generalization. Each error pattern suggests a specific instructional adjustment.

Ethical Considerations

Code 2.01 requires behavior analysts to apply scientifically supported interventions. Intraverbal training procedures — including transfer of control, multiple-exemplar training, and differential reinforcement of verbal responses — are supported by a growing applied literature in JABA and verbal behavior journals. BCBAs who implement intraverbal programs are applying evidence-based methods and should be able to describe the procedural basis and empirical support for the specific teaching formats they use.

Code 2.09 requires least-intrusive procedures. For intraverbal training, this means applying the minimum level of prompting necessary to evoke correct responding, selecting prompt fading procedures that systematically reduce support, and avoiding prompt dependency by attending carefully to the stimulus control exerted by visual or physical prompts. The goal of intraverbal instruction is verbal behavior under verbal control — and prompts that substitute visual or physical stimuli for verbal ones must be faded deliberately.

Code 1.05 addresses cultural responsiveness, which is particularly relevant in intraverbal programming. The conversational topics, question formats, and culturally expected responses used in intraverbal programs should reflect the learner's cultural and linguistic background. Standard English question-answer formats used in many ABA intraverbal programs may not align with the conversational norms of a learner's home community. BCBAs should consult with families and culturally competent colleagues to ensure that intraverbal programs target skills that are functionally relevant and culturally appropriate.

Code 4.05 applies to supervision of RBTs implementing intraverbal programs. The stimulus control subtleties of intraverbal training make it particularly important that supervisees receive direct observation and specific feedback. RBTs who unknowingly prompt intraverbal responses with visual cues, who reinforce echoed responses as correct, or who fail to detect tact intrusions into intraverbal responding are undermining program integrity in ways that self-report in supervision meetings cannot detect.

Assessment & Decision-Making

VB-MAPP Intraverbal assessment provides a developmental framework for identifying the specific intraverbal skills that are present and absent in the learner's repertoire. Assessment items span fill-in tasks, simple questions, category responses, and conversational exchanges at progressive complexity levels. Identifying the specific intraverbal milestones that are not yet mastered guides the selection and sequencing of instructional targets.

Pre-instructional stimulus control assessment clarifies whether a learner is responding to verbal stimuli alone or whether responses are under the control of visual prompts. This can be tested by presenting intraverbal questions in an environment that removes visible related stimuli and observing whether response accuracy is maintained. If accuracy drops dramatically in the absence of visual supports, the intraverbal program needs to address stimulus control before expanding to new targets.

Selection of initial intraverbal targets should be guided by functional relevance, motivational salience, and current repertoire. Fill-in tasks based on preferred songs, games, or phrases are excellent starting points for early intraverbal instruction because the motivating conditions for the response are naturally embedded in activities the learner already enjoys. Targeting intraverbals that generalize to high-frequency social contexts — greetings, common classroom questions, snack and play interactions — maximizes the functional impact of early instruction.

Decision rules for intraverbal programs should specify mastery criteria, generalization criteria, and data review schedules. Given the generative nature of intraverbal behavior, mastery of a small set of trained exemplars may not be sufficient — programs should include multiple-exemplar training and generalization probes to ensure that trained responses are not rigidly stimulus-specific.

What This Means for Your Practice

Intraverbal deficits are often the gap between a learner who 'talks' and a learner who 'communicates.' Identifying and systematically addressing intraverbal skills is one of the most important things you can do for learners who have emerging verbal behavior but limited social language. Do not wait for conversational language to emerge naturally from mand and tact repertoires — it rarely does without direct instruction.

When training RBTs and ABATs in intraverbal procedures, invest time in teaching the conceptual distinction between verbal operants. Staff who understand the difference between a tact response, a mand, and an intraverbal are far better equipped to detect and correct the stimulus control errors that undermine intraverbal programs.

Naturalistic teaching opportunities for intraverbals occur constantly in the learner's day. During snack, 'What are you eating?' During transitions, 'Where are you going?' During play, 'What do you want to do next?' Training families and teachers to capitalize on these moments — to ask the question and wait for the response rather than narrating for the learner — dramatically increases the density of intraverbal practice and supports generalization to the natural environment.

Regularly audit your intraverbal programs for evidence of genuine verbal control. Conduct periodic probes in novel environments without visual supports. Check whether responses generalize across novel question forms that address the same content. Examine error patterns for evidence of echoic or tact intrusion. Intraverbal programs that are technically being implemented but that are actually producing tact or echoic behavior rather than intraverbal behavior need immediate revision.

Finally, target conversational intraverbals even for learners who are in early stages of language development. Simple conversational exchanges — greeting routines, turn-taking with single-word responses, commenting on ongoing activities — are age-appropriate and functionally significant targets that can be built into naturalistic teaching from early in a program.