A common language: using B.F. Skinner's verbal behavior for assessment and treatment of communication disabilities in SLP-ABA.

Abstract

Professionals in the field of speech-language pathology (SLP) and applied behavior analysis (ABA) share a common goal in the treatment of communication disorders. The two fields, however, do not share a common language. Skinner's definition of verbal behavior and his classification of verbal operants provide interventionists with a valuable tool for classifying verbal behavior based on controlling variables. An understanding of the primary verbal operants and operants under multiple control are essential for planning efficient verbal behavior intervention. This paper presents a primer on B.F. Skinner's 1957 publication, Verbal Behavior, a description of the primary verbal operants, verbal operants under multiple control, and a discussion of using this taxonomy for writing precise communication goals for effective intervention.

Keywords: Speech-Language Pathology, Applied Behavior Analysis, B.F. Skinner, verbal behavior, verbal operants, communication intervention.

Introduction

During the last decade there has been a growing trend for direct collaboration between the fields of speech-language pathology (SLP) and applied behavior analysis (ABA). A common overlap between the focus of the two fields is in the area of communication assessment and intervention for the purposes of enhanced interaction skills and management of inappropriate behaviors resulting from inadequate communication skills (Koenig and Gerenser, 2006). Disagreements among professionals from both fields often can be a result of a difference in terminology. Take for example, the definition of the term "communication." A definition adopted by the American Speech-Language Hearing Association was developed by the National Joint Committee for the Communicative needs of Persons with Severe Disabilities (1991, p. 2).

   Any act by which one person gives to or receives from another
   person information about that person's needs, desires, perceptions,
   knowledge or affective states. Communication may be intentional or
   unintentional, may involve conventional or unconventional signals,
   may take linguistic or nonlinguistic forms, and may occur through
   spoken or other modes.

This definition emphasizes the shared meaning established between a speaker and a listener. The Joint Committee concluded, "Thus, all persons do communicate in some way." Additionally, the success of a communicative exchange could depend on the listener happening to witness the speaker's behavior and interpreting that behavior as communicative.

The 1957 publication of B.F. Skinner's Verbal Behavior provided the field of ABA with a definition of communication. Skinner refers to "verbal behavior" as "...behavior reinforced through the mediation of other people ... (p.2)" and specified that "... the 'listener' must be responding in ways which have been conditioned precisely in order to reinforce the behavior of the speaker [by the verbal community] ..." In other words, a speaker acts in a manner that is under the stimulus control of an audience (a listener) and the listener then provides the reinforcing consequence. It is through reinforcement of a specific verbal community (the French, the English, the Spanish) that a child learns the grammar and vocabulary of a particular community.

The definitions from both fields emphasize that communication can occur in many modalities, not just the spoken modality. A source of confusion in the field of SLP has been in defining the terms "speech," "language," "communication," and "verbal." Reports of a student including phrases such as "not verbal," or "non-verbal," can lead to erroneous conclusions. A speech pathologist might assume that this means that the student is not yet speaking. A person using Skinner's definition would conclude that the student has no communication skills at all in any modality. The less ambiguous terminology to describe the student who is not speaking would be "non-speaking" or "non-vocal." This could mean that the student has a sophisticated language system in a non-speech modality such as pictures, sign language, or writing.

Skinner's definition also helps us to identify behaviors of a student that are not verbal behavior. Behaviors that lead to direct access to reinforcing consequences are not communicative because access to those consequences is not dependent upon another person. For example if a student goes to a table and picks up a book, we would say that this behavior is not communicative as the action was aimed directly at the book. On the other hand, if the student says to the teacher sitting at the table, "I want that book," and the teacher hands it to the student, we would say that this behavior is verbal behavior.

The purpose of this paper is to provide an overview of Skinner's analysis of verbal behavior and its application to assessment and remediation of communication deficits. A description of Skinner's primary verbal operants will be provided. Then we will discuss analyzing more complex verbal behavior affected by multiple sources of control. Finally, we will describe how an understanding of Skinner's analysis can lead to more effective and efficient teaching strategies.

Historical Overview

Skinner developed the study of operant behaviors- behaviors defined by their impact upon the environment rather than by their form. He initially studied fairly simple non-human animals, such as pigeons, in order to see how systematic changes in consequences (i.e., reinforcers) and antecedents (i.e., state of deprivation, discriminative-stimuli, etc.) can lead to systematic changes in behaviors. He took all of his understanding of how learning occurs and began to apply it to language within a graduate level course for his students at Harvard University. His notes for this class became the basis for the book, Verbal Behavior (1957). After the publication of Verbal Behavior, ABA as a treatment methodology became more accepted in the field of SLP, especially in the area of speech production. Many early training protocols for articulation disorders, stuttering, or voice disorders (see Ogletree and Oren, 2001 for a review) used teaching strategies from the field of ABA. Throughout the recent history of the field of SLP and ABA few training protocols have used Skinner's terminology. A review of the literature a decade ago also yielded few publications using Skinner's analysis (Tarleton and Bondy, 1991).

In recent years training protocols have begun to use Skinner's terminology (Sundberg and Partington, 1998) and a plethora of "verbal behavior" or "applied verbal behavior" treatment programs are now widely available. Verbal Behavior does not directly address intervention, but many practitioners use Skinner's analysis to guide the development of their training protocol (Frost and Bondy, 2002). Additionally, assessment protocols based on Skinner's primary verbal operants are available (Partington and Sundberg, 1998).

Skinner considered it is more useful to understand the functional control of verbal behavior than to focus attention upon its form, stating that, "In defining verbal behavior as behavior reinforced through the mediation of other persons, we do not, and cannot, specify any one form, mode, or medium. Any movement capable of affecting another organism may be verbal (p. 14)." In other words, Skinner's analysis was based on defining what he called verbal operants in terms of their consequences and relatively narrowly defined stimulus conditions.

Skinner identified four controlling antecedent variables of verbal behavior: some state of deprivation or aversive stimulation, some aspect of the environment, other verbal behavior, and one's own verbal behavior. He also identified two consequence conditions: something related to the state of deprivation/aversive stimulation or social (what Skinner referred to as "educational") consequences. His analysis was based on these variables as they occur in isolation or in combination. In describing these operants, he developed new terminology to describe these functional relations to minimize confusion with lay terminology or vocabulary from other professions.

The Primary Verbal Operants

The mand (from command, demand and countermand) is a verbal operant "in which the response is reinforced by a characteristic consequence and is therefore under the functional control of relevant conditions of deprivation or aversive stimulation" (p. 35-36). The mand does not occur in response to a specific stimulus. Rather, the mand is under the control of motivational operations (MO), which increase the power or effectiveness of the reinforcer and is under the stimulus control of the presence of the audience which is necessary for all verbal behavior. An MO may momentarily increase the value of a specific reinforcer and thus increase the likelihood of behaviors that have produced a specific reinforcer in the past. For example, extreme thirst would serve as an MO for requesting a drink. Fear of snakes would serve as an MO for asking to leave the reptile house at the zoo. Examples of mands include requesting food and toys, requesting information, saying "no" or "yes" to an offered item, asking for a break, and asking for assistance.

The tact is evoked by "a particular object or event or property of an object or event (p. 82)." Skinner was referring to some contact with the stimulating environment as the evoking stimulus. This operant is commonly referred to as a comment or a label.

Skinner coined the term intraverbal to refer to verbal behavior that is produced in response to other verbal behavior but is not similar in form to the preceding verbalization. Early in development, intraverbals occur in response to verbalizations produced by someone else. As a child's verbal repertoire matures, intraverbals may also occur in response to the child's own prior verbalizations. Common examples of intraverbals would include answering questions such as "Where do you live?" "What's two plus two?" or filling in the blank as when children respond, "farm" after hearing "Old McDonald had a ..."

The echoic is similar to the intraverbal in that it occurs in response to other verbal behavior, but the resulting verbal behavior matches the form of the verbal stimulus. For example, imitation of sounds, words, or entire phrases would be considered echoics.

The autoclitic is the most complex of the verbal operants. The autoclitic is under the control of the speaker's own verbal behavior ('auto-clitic' means 'self-leaning') and serves to cause a subtle impact on the listener. For example in the phrase, "I think it's going to rain," versus "I'm sure it's going to rain," the speaker is not referring to some aspect of the rain, but rather is referring to some aspect of himself or something that controls his verbal response. The phrases "I think" and "I'm sure" tell the listener about the intensity of the speaker's conviction regarding the impending rain. If it doesn't rain, the potential negative response from the listener is less severe in response to the autoclitic "I think," than it would be in response to "I'm sure."

Skinner defined two broad categories of reinforcement. The mand is unique in that it specifies its own consequence. In other words, the speaker makes clear what the reinforcer should be. The other operants are established and maintained by the verbal community through what Skinner called "educational reinforcers" such as "Right!" "Good job." These reinforcers are commonly referred to as social reinforcers. Table 1 presents a summary of the three-term contingency for each of the primary verbal operants.

Multiply Controlled Verbal Operants

The primary verbal operants described above are specifically defined by the controlling variables. When only those stimulus and consequence conditions are present, Skinner refers to these operants as "pure." Skinner also describes these operants in terms of multiple control. When there is "...a mixture of controlling relations...We might speak of [these as] 'impure'... (p.151)." For example, if a teacher were to hold up a picture of a house and say, "What's this?" the student's response, "house" would be under the control of two antecedent conditions- the teacher's question and the picture. Similarly, if the teacher routinely held up items and said, "What's this?" and then gave those items to the student after he answered, then the source of the mixed control is in the ambiguous consequences the teacher provides.

Many potential sources of "impurity" exist, depending on various combinations of stimulus and consequence factors. A variety of multiply controlled verbal operants controlled by combinations of both stimuli and controlling consequences are listed in Table 2. It is this multiple control that often sets the stage for a student's "failure" to master a particular communication objective. For example, a common complaint of teachers about their students is that the students are not "spontaneous" or that they are "prompt dependent." Rather than a symptom of a disability or a student's level of intellectual functioning, a lack of spontaneity may be directly related to the teacher's use of controlling variables during training. A teacher might report that a student only asks for desired items upon hearing, "What do you want?" or when the available items are in sight. If the only lesson a teacher has arranged is one in which the question is asked and the items are shown, then the student will learn to ask for items only in response to these two variables (in addition to the MO). It is the teacher's responsibility to manipulate the controlling variables at play during a lesson.

A Skinnerian analysis of the generic treatment goal, "Student will request desired items," identifies a variety of stimulus conditions that could result in the student engaging in this behavior as depicted in Table 3.

Finding the source of the student's lack of spontaneity involves analyzing the antecedent conditions present during training. If a teacher routinely shows a student available items while asking "What do you want?" then we should not expect the student to ask for a cookie in the absence of the cookie or the question. The same problem arises when teachers report that a student has "failed to generalized" from treatment to more naturalistic settings. For example, if the treatment goal is "name items" a variety of stimulus combinations could yield this outcome (Table 4).

A more precise description of the original goal of training would be important in identifying the specific operant to teach. For example, "Student will request desired items," could be rewritten as "Student will respond to "What do you want?" when the item is present." The intended final operant in this case would be the intraverbal/mand/tact. If the intention is for the student to use a pure mand (spontaneously request), then the goal should be written as follows: "Student will ask for desired items without the item in sight and without questions/prompts from the teacher." In this case, the teacher must ensure that the MO is the only controlling antecedent variable and that the appropriate reinforcement (direct) is supplied. If the teacher initially teaches this goal by asking the question, "What do you want?" and by showing the student the available items, then the teacher's verbal behavior and the presence of the items also influence the student's behavior. Across training opportunities the teacher must eliminate these additional sources of control using various stimulus transfer or stimulus fading procedures.

Efficient teaching involves establishing a goal to teach a specific verbal operant and then designing lessons that will require the fewest number of steps to reach that goal. If the final goal is a pure mand, the most effective teaching strategy would involve beginning with the fewest possible sources of control so that there are fewer to eliminate. For a more complete description of this type of analysis of communication training protocols, see Bondy, Tincani, and Frost, 2004. Conclusion

The benefit of a common system of analysis with precise labels for specific behaviors across both the SLP and ABA disciplines is in the impact on teaching verbal behavior to children in a therapeutic setting. Table 5 demonstrates how using the specific vocabulary of Skinner's verbal operants can help clarify some of the ambiguous terminology in use within the SLP literature.

The power behind the book Verbal Behavior lies in its systematic analysis of factors that influence communication. By identifying the controlling factors for a child's current communication skill we can begin to plan how to move from the current situation to our teaching goal. In this manner, we can see the steps (and how many may be needed) between what the child currently can do and what we would like to see the child perform. With the beginning and end of our lessons clearly identified we will be able to design and implement more effective lessons using any modality.

References

Bondy, A., Tincani, M. & Frost, L. (2004). Multiply controlled verbal operants: An analysis and extension to the Picture Exchange Communication System. The Behavior Analyst, 27,247-261.

Frost, L. & Bondy, A. (2002). The Picture Exchange Communication System (PECS) Training Manual, 2nd Edition. Newark, DE: Pyramid Educational Products, Inc.

Koenig, M. and Gerenser, J. (2006). SLP-ABA: Collaboration to support individuals with Communication Impairments. Journal of Speech Language Pathology and Applied Behavior Analysis, 1 (1), 2-10.

National Joint Committee for the Communicative Needs of Persons with Severe Disabilities. (1992, March). Guidelines for meeting the communication needs of persons with severe disabilities. [Electronic Version] Asha, 34, 1-8. Retrieved May 2, 2006, from http://www.asha.org/NJC/njcguidelines.htm

Ogletree, B.T. & Oren, T. (2001) Application of ABA principles to general communication instruction. Focus on Autism and Other Developmental Disabilities. 16, (2), 102-109

Skinner, B. F. (1957). Verbal behavior. Englewood Cliffs, NJ.: Prentice-Hall.

Sundberg, M.L. & Partington, J.W. (1998). Teaching language to children with autism or other developmental disabilities. Behavior Analysts, Inc.: Danville, CA.

Tarleton, R. and Bondy, A. (May, 1991). Tumbling the Tower of Babel: An analysis of verbal operants in JABA. Presented at the Association for Behavior Analysis convention, Atlanta, GA.

Author contact information:

Lori Frost, M.S., CCC-SLP 

Pyramid Educational Consultants, Inc.

226 W. Park Place

Suite 1

Newark, DE 19711

Phone: [phone]

E-mail: [e-mail]

Andy Bondy, Ph.D.

Pyramid Educational Consultants, Inc.

226 W. Park Place

Suite 1

Newark, DE 19711

Phone: [phone]

E-mail: [e-mail]

Table 1. Elementary Verbal Operants and Controlling Variables

   Antecedent           Consequence        Verbal Operant

X MO                X direct               Mand
? Environment       ? educational/social
? Verbal behavior

? MO                ? direct               Tact
X Environment       X educational/social
? Verbal behavior

? MO                ? direct               Intraverbal
? Environment       X educational/social
X Verbal behavior

? MO                ? direct               Echoic
? Environment       X educational/social
X Verbal behavior

? MO                X direct               Autoclitic
? Environment       ? educational/social
X Verbal behavior

   Antecedent             Example

X MO                Mary walks into kitchen where Mom is
? Environment       sitting and says, "I want some milk!"
? Verbal behavior   Mom opens the refrigerator and gives
                    Mary some milk

? MO                Johnny, looking out the window, turns
X Environment       to his teacher and says, "It's hot today."
? Verbal behavior   His teacher says, "It sure is!"

? MO                Mom asks Tomasina, "How'd you do on
? Environment       your project?" Tomasina says "I got a
X Verbal behavior   B." Mom says, "Great!"

? MO                Mrs. Thompson says to Mary, "The
? Environment       capital of New Jersey is Trenton." Mary
X Verbal behavior   says, "The capital of New Jersey is
                    Trenton." Mrs. Thompson says, "Yes!"

? MO                Michael wakes his dad up during the
? Environment       night and says, "I think I'm going to be
X Verbal behavior   sick." His dad rushes him to the
                    bathroom."

MO= Motivational Operation
Environment= Stimulating aspect of the environment
Verbal behavior= verbal behavior of someone else
Direct= Related to MO
Educational/social= social consequence provided by a listener

Table 2. Complex Verbal Operants and Controlling Variables

   Antecedent           Consequence            Verbal Operant

X MO                X direct
X Environment       X educational/social   Mand-Tact
? Verbal behavior

X MO                X direct               Intraverbal-Mand
? Environment       X educational/social

X Verbal behavior

X MO                X direct               Intraverbal-Mand-Tact
X Environment       X educational/social
X Verbal behavior

? MO                ? direct               Intraverbal-Tact
? Environment       X educational/social
X Verbal behavior

? MO                ? direct               Echoic Tact
? Environment       X educational/social
X Verbal behavior

? MO                ? direct               Intraverbal-Echoic
? Environment       X educational/social
X Verbal behavior

? MO                ? direct               Echoic-Intraverbal-Tact
X Environment       X educational/social
X Verbal behavior

   Antecedent             Example

X MO                Terrence walks into the classroom, sees
X Environment       cupcakes and shouts "Cake!" His
? Verbal behavior   teacher gives him cake.

X MO                At the store while looking at school
? Environment       supplies, Mom asks, "What color note
                    book do you want? Sam answers
X Verbal behavior   "Blue." Mom buys blue.

X MO                Holding a ball, Mr. Johnson says, "What
X Environment       do you want?" and Nathan responds,
X Verbal behavior   "Ball." Mr. Johnson gives the ball.

? MO                Pointing to a picture on the wall, Ms.
? Environment       Baker asks, "Who's that?" and Sue
X Verbal behavior   responds, "Mom."

? MO                Standing next to a window and
? Environment       observing a rain shower, Ms. Reed,
X Verbal behavior   says, "rain," and Amanda responds,
                    "rain."

? MO                Ms. Tuil says, "What's two plus two?
? Environment       Say "four" and Julie responds "Four,"
X Verbal behavior   and Ms. Tuil says, "That's right."

? MO                Mr. Ryan holds up a pencil and says,
X Environment       "Say "pencil.'" John responds, "Pencil."
X Verbal behavior   Mr. Ryan says, "Great!"

MO= Motivational Operation
Environment= Stimulating aspect of the environment
Verbal behavior= verbal behavior of someone else
Direct= Related to MO
Educational/social= social consequence provided by a listener

Table 3. Potential Sources of Multiple Control of the Mand

Operant                 Antecedent                    Student Behavior:

Pure Mand               MO- no cookie around          "Cookie"
Tact/Mand               Cookie in sight               "Cookie"
Echoic/Mand             MO + teacher                  "Cookie"
                          says "Cookie"
Intraverbal/Mand        Teacher says, "What do        "Cookie"
                          you want?"
Intraverbal/Mand/Tact   Cookie in sight, Teacher      "Cookie"
                          says, "What do you want?"

Table 4. Multiple Control of the Tact

    Operant                  Antecedent              Student Behavior

Pure Tact          Sound of fire truck               "Fire truck"
Intraverbal/Tact   Sound of fire truck and           "Fire truck"
                     teacher asking,
                     "What do you hear?"
Echic/Tact        Sound f fire truck, Teacher        "Fire truck"
                     saying, Fire truck"
Intraverbal/       Sound of fire truck and           "Fire truck"
  Echic/Tact       teacher asking, What do
                     you hear? Say, 'fire
                     truck.'"

Table 5. Terminology for Verbal Behavior and
Speech Language Pathology

VB terms                SLP terms
Pure Mand               Request
Tact-Mand               Request
Echoic-Mand             Request
Intraverbal-Mand        Request
Intraverbal-Mand-Tact   Request
Pure Tact               Comment
Intraverbal Tact        Comment
Echoic Tact             Comment