The Duplic and Codic: the Importance of a Consistent Taxonomy of Verbal Behavior.

The authors looked at how we talk about 'transcription' in verbal behavior. They said the word is fuzzy. It can mean copying spoken words or copying written words.

They proposed two clean labels. 'Duplic' for copying spoken words. 'Codic' for copying written words. They want every book and chart to use these terms.

No new data were collected. The paper is a map. It shows how one muddy term splits into two clear streams.

The map helps teachers, supervisors, and app makers speak the same language.

Abbott (2013) set the stage. That paper told us to stop arguing about definitions and look at what makes us use them. Smit et al. (2019) follow the same rule: they looked at how the verbal community uses 'transcription' and offered a fix.

Becker et al. (2022) extends the idea. Their aphasia review says clinicians should use Skinner’s verbal operants. The duplic/codic split gives those clinicians sharper tools when they test copying skills after brain injury.

Embregts (2000) refined 'establishing operation.' Smit et al. (2019) repeats the trick for another concept. Both papers tidy up the vocabulary so practitioners can write clearer protocols.

If you write lesson plans, supervise RBTs, or build data sheets, pick one label and stick with it. Say 'duplic' when the client repeats what you say. Say 'codic' when the client copies text. Your team will score responses the same way every time. No more guessing if 'transcription' means spoken or written. Clear words make clean data.

A duplic is a verbal operant in which the response has both point-to-point correspondence and formal similarity with its controlling verbal stimulus: the response duplicates the stimulus in the same sense mode. The duplic family includes the echoic (hear a word, say the same word), motor imitation of signs (see a sign, produce the same sign), and copying a text (see written words, write the same words). Jack Michael proposed the term to give these three a common label.

A codic is a verbal operant with point-to-point correspondence but no formal similarity: each unit of the stimulus controls a unit of the response, but the stimulus and the response product are in different forms. The codic family includes textual behavior (see the written word 'ball,' say 'ball') and taking dictation (hear the word 'ball,' write 'ball'). The response encodes the stimulus into a different medium rather than duplicating it.

The umbrella terms exist because Skinner's original taxonomy left this corner messy. The word 'transcription' has been used by different textbooks to mean taking dictation only, or copying a text, or both, and this paper documents those inconsistencies across published behavior-analytic references. When a term means different things in different training materials, targets get misclassified and data stop lining up, which is the authors' core argument for adopting duplic and codic consistently.

Run each example through two questions. Does each part of the stimulus control a matching part of the response (point-to-point correspondence)? And does the response resemble the stimulus in the same form (formal similarity)? Both yes means duplic. Correspondence without resemblance means codic.

Duplic examples: a therapist says 'cookie' and the learner says 'cookie' (echoic: vocal stimulus, vocal response, same form). A therapist models the sign for 'more' and the learner produces the sign (imitation as verbal behavior: visual stimulus, motor response of the same topography). A student sees the written word 'dog' and writes 'dog' (copying a text: written to written).

Codic examples: a student sees the written word 'dog' and says 'dog' out loud (textual: written stimulus, vocal response). A student hears 'dog' and writes it down (taking dictation: vocal stimulus, written response). In both cases every letter or sound maps to a response unit, but the form changes, so there is no formal similarity and no duplication.

For BCBA exam preparation the discriminations to rehearse are exactly these: echoic, sign imitation, and copying text are duplics; textual and dictation-taking are codics. If you are tempted to write 'transcription' on a program, name the actual operant instead so the next clinician measures the same behavior you did.