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Noncontingent reinforcement as treatment for tub-standing in a toddler.

Noncontingent reinforcement (NCR (NCR Corporation, Dayton, OH, A technology company specializing in financial terminal transactions, retail systems and data warehousing. Until the late 1990s, NCR was heavily invested in the hardware side of the industry, known worldwide as a major manufacturer of computers ) has been widely used in recent years as a treatment for problem behavior in populations diagnosed with developmental disabilities (see Carr et al., 2000 for review). Boe (1977) first described this method of treatment. He used noncontingent presentation of variable-time food (VT) to reduce aggressive behavior in a group of women diagnosed with mental retardation mental retardation, below average level of intellectual functioning, usually defined by an IQ of below 70 to 75, combined with limitations in the skills necessary for daily living. . Similarly, Thelen (1979) used noncontingent delivery of attention to reduce tantrum tan·trum
A fit of bad temper.

n a sudden outburst or violent display of rage, frustration, and bad temper, usually occurring in a maladjusted child or immature or disturbed adult.
 behavior in an 8-year old girl.

Most treatment programs that employ NCR do so in a function-based manner. The reinforcing consequence that maintains the problem behavior is identified through a functional analysis (e.g., Iwata, Dorsey, Slifer, Bauman, & Richman, 1994), and is then presented noncontingently according to according to
1. As stated or indicated by; on the authority of: according to historians.

2. In keeping with: according to instructions.

 some time-based schedule, generally fixed time (FT). During NCR treatment, if the problem behavior occurs, there is generally a response programmed into the intervention. For example, extinction extinction, in biology, disappearance of species of living organisms. Extinction occurs as a result of changed conditions to which the species is not suited.  is widely used in conjunction with NCR for socially maintained problem behaviors (e.g., Vollmer, Iwata, Zarcone, Smith, & Mazaleski, 1993), and another method, such as response blocking, is generally used in conjunction with NCR when problem behavior is automatically reinforced (e.g., Piazza piazza

Open square or marketplace, surrounded by buildings, in an Italian town or city. It was equivalent to the plaza of Spanish-speaking countries. The term became more widely used in the 16th–18th century, denoting any large open space with buildings around it.
, Hanley, & Fisher, 1996).

Noncontingent reinforcement has been shown to be effective for a variety of problem behaviors, including those maintained by attention (e.g., Hagopian, Fisher, & Legacy, 1994; Vollmer et al., 1993), escape from or avoidance of instructional demands (e.g., Khang, Iwata, DeLeon, & Worsdell, 1997), and access to materials (e.g., Lalli, Casey, & Kates, 1997). In addition, NCR has been shown to be an effective treatment for other socially inappropriate behavior, including aggression (e.g., Vollmer, Ringdahl, Roane, & Marcus, 1997), rumination rumination /ru·mi·na·tion/ (roo?mi-na´shun)
1. the casting up of the food to be chewed thoroughly a second time, as in cattle.

 (e.g., Wilder, Draper drap·er  
n. Chiefly British
A dealer in cloth or clothing and dry goods.

[Middle English, weaver or seller of cloth, from Old French drapier, from drap, cloth; see
, Williams, & Higbee, 1997), disruption (e.g., Fisher, Ninness, Piazza, & Owen-DeSchryver, 1996), inappropriate speech (e.g., Carr & Briton, 1999), and pica (e.g., Piazza et al., 1998).

Aside from being effective, NCR has several benefits over other treatment options (see Carr & LeBlanc, in press, for discussion). First, most NCR procedures present the reinforcer reinforcer /re·in·forc·er/ (-in-for´ser) any stimulus that produces reinforcement, a positive r. being a desirable event strengthening responses preceding its occurrence and a negative r.  responsible for maintenance of the problem behavior, rather than trying to mask the reinforcing contingency through some other method. Another benefit of NCR is that it appears to be as effective, if not more so, than several other common behavior-change procedures, such as differential reinforcement of other behavior (DRO DRO Digital Readout
DRO Detention and Removal Operations (US Immigration and Customs Enforcement)
DRO Domestic Relations Order
DRO Department of Radiation Oncology
DRO Dielectric Resonator Oscillator
DRO Destructive Read Out
; Vollmer et al., 1993), functional communication training (FCT FCT Faculdade de Ciências e Tecnologia (Portuguese University)
FCT Fundamentals of Computation Theory
FCT Fundação para a Ciência e a Tecnologia (Portuguese Science and Technology Foundation) 
; Hanley, Piazza, Fisher, Contrucci, & Maglieri, 1997), and extinction (Vollmer et al., 1998). In addition, NCR has been shown to be an effective treatment for automatically reinforced problem behavior, particularly when the noncontingent reinforcement is matched to the same or similar stimulus modalities Modalities
The factors and circumstances that cause a patient's symptoms to improve or worsen, including weather, time of day, effects of food, and similar factors.
 as the reinforcer maintaining the problem behavior (Higbee, Chang, & Endicott, 2005; LeBlanc, Patel, & Carr, 2000). Finally, NCR is a more positive procedure for both client and clinician clinician /cli·ni·cian/ (kli-nish´in) an expert clinical physician and teacher.

 than other traditional behavior-reducing procedures, as evidenced by more reinforcer deliveries than under DRO methods (Vollmer et al., 1993), and less extinction-induced behavior than DRO or extinction (Vollmer et al., 1993; Vollmer et al., 1998).

Although many uses of NCR are function-based (present the reinforcer maintaining the behavior as identified through a functional analysis), this need not be the case in order for NCR treatments to be effective. In some cases, identification of the reinforcer maintaining a given problem behavior may be difficult or not possible. Furthermore, in the case of automatically reinforced behavior, it may not be possible for the reinforcer maintaining the problem behavior to be withheld. In these cases, treatment involving arbitrary NCR may be beneficial. For example, Hanley, Piazza, and Fisher (1997) assessed the effectiveness of arbitrary NCR treatment on destructive behavior that was attention maintained. They identified highly-preferred stimuli through a preference assessment and then presented these stimuli noncontingently. Their results showed that noncontingent presentation of a highly-preferred stimulus reduced destructive behavior to the same degree that presentation of noncontingent attention did, suggesting that the tangible items were to some extent substitutable for attention. In this study, the destructive behavior was placed on extinction, but others have shown that arbitrary NCR is effective even when the problem behavior still produces the maintaining reinforcer (e.g., Fisher, Iwata, & Mazalenski, 1997; Lalli et al., 1997). These results suggest that although function-based NCR is preferred when possible, arbitrary NCR can be effective in reducing problem behavior, and is therefore a viable treatment option.

Although extensive research has been conducted on the effects of NCR treatment on a variety of problem behaviors in individuals diagnosed with developmental disabilities and other disorders, there has been relatively little investigation of NCR as treatment for problem behavior in typically-developing children. Thus, the primary purpose of the present case study was to evaluate the effectiveness of NCR as a treatment for a socially relevant problem behavior (problematic standing in the tub at bath time, hereafter In the future.

The term hereafter is always used to indicate a future time—to the exclusion of both the past and present—in legal documents, statutes, and other similar papers.
 tub-standing) in a typically-developing toddler. A secondary purpose was to evaluate the feasibility of conducting a functional analysis on this socially relevant problem behavior in the home environment.


Participant and Setting

The participant, Maude, was a typically-developing 16-month old child. All sessions lasted 20 min and were conducted during her regular bath time at approximately 8:30 P.M. Sessions were generally conducted on Tuesday, Thursday, Saturday, and Sunday. Sessions were not conducted on Monday, Wednesday, or Friday because Maude went swimming on those days, after which she was bathed at the swimming facility.

Response Definition and Measurement

The target behavior was tub-standing, defined as both feet flat on the tub floor and both hands off of the tub floor. Tub-standing is particularly dangerous for young children because they can slip on the smooth surface of the tub and fall. In fact, slips and falls accounted for 82% of bathtub injuries in children in a recent study (Columbus Children's Research Institute, 2005). Thus, interventions that decrease this behavior are desirable. For the purposes of this study, instances where standing was assisted (holding on to the side of the tub, faucet, etc.) or unassisted were not differentiated. Data collected were the number of tub-stands per 20 min session. This method of data collection was chosen because it provides an accessible picture of the overall frequency of the target behavior.

Functional Analysis

Functional analysis procedures were similar to those used by Iwata et al. (1994). Preliminary observation suggested that tub-standing was not maintained by escape (no incident ever resulted in getting out of the tub or elimination of task demands), and was also not maintained by access to tangibles (bath toys were generally freely available during tub time). Therefore, a brief functional analysis with two conditions, attention and alone, was conducted in an alternating-treatments design in which functional-analysis conditions were alternated across successive days. Each functional-analysis condition was conducted for four days, for a total of eight days of functional analysis.

During the attention condition of the functional analysis, the participant was placed in the tub without access to bath toys or other tangibles, and all incidences of tub-standing resulted in the delivery of contingent attention in the form of a verbal prompt delivered by the experimenter to sit down (e.g., sit down, please, you are going to hurt yourself). This condition was conducted to assess whether tub-standing was maintained by parent attention. During the alone condition, the participant was placed in the tub without access to bath toys or other tangibles and all incidences of tub-standing were recorded. This condition was conducted to determine if tub-standing would be maintained regardless of the social consequences for this behavior (i.e., automatically reinforced). Due to the safety hazard produced by tub-standing, during the attention condition of the functional analysis if tub-standing was not terminated within 5 s following the verbal prompt, the participant was forcibly forc·i·ble  
1. Effected against resistance through the use of force: The police used forcible restraint in order to subdue the assailant.

2. Characterized by force; powerful.
 sat down on the tub floor (modified response blocking). In the alone condition of the functional analysis, there were no verbal prompts on occurrence of tub-standing, but the participant was forcibly sat down on the tub floor 5 s after any instances.

Noncontingent Reinforcement

Following the functional analysis, three sessions of baseline were conducted. These sessions were identical to the alone condition of the functional analysis. Following three baseline sessions, noncontingent reinforcement treatment began. During noncontingent reinforcement sessions, the participant was placed in the tub and the experimenter delivered access to bath toys on a FT schedule in which the participants' behavior did not influence the frequency of reinforcement. The bath toys used were foam alphabet letters and numbers, plastic cups of varying sizes, rubber sea animals that could be filled with water and squirted, and a bath-time book with pictures of various sea animals. These toys were chosen for inclusion on the basis of approximately 6 months of preliminary observation of the participant at bath time and were all highly-preferred toys. When the FT interval timed out, Maude was given access to a randomly chosen bath toy for 30 s, after which the toy was removed from the tub. Following the next elapsed e·lapse  
intr.v. e·lapsed, e·laps·ing, e·laps·es
To slip by; pass: Weeks elapsed before we could start renovating.

 interval, another toy was presented. This treatment regimen regimen /reg·i·men/ (rej´i-men) a strictly regulated scheme of diet, exercise, or other activity designed to achieve certain ends.

 continued until the end of the session. The initial FT schedule value was FT 2 min. This value was then thinned to an FT 5 min schedule. Tub-standing increased under FT 5 min, so the schedule density was increased to FT 3 min. As in the functional analysis, all instances of tub-standing were blocked. Thus, the present treatment constituted a NCR without extinction procedure.

Results And Discussion

Functional Analysis

Figure 1 shows the results of the functional analysis. During the attention condition, tub-standing occurred on average 9.5 times per session. During the alone condition, tub-standing occurred at a higher rate, on average 14.8 times per session. In addition, the number of tub-stands per session during the attention condition was highly variable, while under the alone condition the number of tub-stands was more stable across sessions. These results suggest that tub-standing was maintained simply by stimulation produced by the act of standing itself (i.e., automatic reinforcement).

NCR Treatment

Figure 2 shows that the number of tub-stands during the three baseline sessions was similar to that seen in the alone condition of the functional analysis, with an average of 12.3 times per session. Following implementation of NCR 2 min, tub-standing was decreased to 1 stand per session, and remained low for the four days that NCR 2 min was in effect. Following schedule-thinning to NCR 5 min, tub-standing increased to around eight times per session. When the NCR schedule density was increased to NCR 3 min, tub-standing decreased to one stand per session and did not occur for the last two sessions of NCR treatment.

These results are related to several areas. First, the results of the functional analysis suggested that tub-standing was maintained by automatic reinforcement. This type of automatic reinforcement may be, and probably is, different from the type that is thought to influence other types of problem behavior. For Maude, who has been walking for a relatively brief period of time, standing and walking appear to be reinforcing in and of themselves, and the results of the functional analysis suggest that simply standing may have been reinforcing enough to maintain itself even in the absence of other differential consequences. This result suggests that highly preferred activities, particularly those that have been relatively recently learned, may be "automatically" reinforcing. If this were the case, one might expect tub-standing to decrease without intervention as the novelty of it fades. Conclusions as to whether this type of "automatic" reinforcement is similar in kind to other types of automatic reinforcement, such as perceptual (e.g., visual) or sensory (e.g., oral) stimulation must await further research.



The results of the present case study provide further support for the efficacy of NCR as treatment for problem behavior. Previous NCR studies have generally been conducted in extremely-controlled clinical settings, and little research has been conducted on the feasibility or utility of NCR as an intervention in naturalistic nat·u·ral·is·tic  
1. Imitating or producing the effect or appearance of nature.

2. Of or in accordance with the doctrines of naturalism.
 settings (see Carr et al., 2000, for discussion). The results of the present case study suggest that implementation of an effective NCR treatment for problem behavior in a typically-developing child may be accomplished in a relatively brief amount of time in a naturalistic setting. Future research should more clearly delineate and circumscribe cir·cum·scribe  
tr.v. cir·cum·scribed, cir·cum·scrib·ing, cir·cum·scribes
1. To draw a line around; encircle.

2. To limit narrowly; restrict.

3. To determine the limits of; define.
 the types of problem behaviors, natural settings, and conditions that contribute to or limit the use of NCR as an effective problem-behavior reducing procedure.

The results from the present functional analysis are encouraging because they suggest that empirically-validated methods for determining behavioral function that have long been employed in structured settings such as laboratories, clinics, and schools may also be used by practitioners, parents, or other caregivers in the home. Specifically, these results suggest that the reinforcer maintaining common problem behaviors in typically-developing children may be identified using an easily-implemented functional analysis in the child's home environment. Future research should assess the utility of functional analyses in identifying behavioral function of other commonly-encountered problem behaviors in typically-developing children.

The primary limitation of the present case study is that it involved only one subject. There are no other data on treatments for tub-standing in toddlers, and therefore the generality gen·er·al·i·ty  
n. pl. gen·er·al·i·ties
1. The state or quality of being general.

2. An observation or principle having general application; a generalization.

 of the present results is unclear. Another limitation of the present case study was that, due to the dangerous nature of tub-standing, any instances of tub-standing were followed by forcibly sitting the child down in the tub. Particularly during the alone condition of the functional analysis, this course of action could be argued to have produced a consequence for tub-standing, thus undermining the function of the alone condition. Aside from structural changes to the tub, however, this was the only viable approach. Furthermore, the different results from the attention and alone conditions of the functional analysis, both of which included this modified response blocking, suggest that the reinforcer maintaining tub-standing was differentiated by these conditions. Thus, notwithstanding the response-blocking procedure, the results of the functional analysis appear valid.

Another potential limitation of the present case study is that the items delivered under the NCR schedules were not chosen on the basis of a formal preference assessment. It has been shown that arbitrary NCR without extinction (as in the present study) is effective only when highly preferred items are delivered during NCR (e.g., Fisher, O'Connor, Kurtz, DeLeon, & Gotjen, 2000). In the present case study, preference for stimuli delivered during NCR was not formally assessed, but observation for several months prior suggested that all of the stimuli used were highly preferred items. In addition, the results of the NCR manipulations are clear; NCR resulted in large and lasting decreases in tub-standing. Thus, although the lack of formal preference assessment in the present study is less desirable from an experimental standpoint, the treatment data clearly show that the intervention was effective nonetheless. A final limitation is that formal interobserver agreement data were not collected during the case study. While the target behavior was clearly defined and easily detected, this may limit the validity of the current results. Future researchers should examine the effects demonstrated in the present study utilizing more formal research controls.

In conclusion, the decreases in tub-standing under NCR provide further evidence that NCR is an effective problem-behavior reducing procedure. In addition, because the nature of the NCR was not specifically matched to any known reinforcing stimulus Noun 1. reinforcing stimulus - (psychology) a stimulus that strengthens or weakens the behavior that produced it
reinforcer, reinforcement

stimulant, stimulus, stimulation, input - any stimulating information or event; acts to arouse action
 properties, these results may lend support to the assertion that arbitrary NCR can be a productive treatment intervention when behavioral function cannot be identified. Finally, these results suggest that NCR may be an effective treatment to reduce dangerous or problem behaviors in typically-developing children in naturalistic settings.


Boe, R. B. (1977). Economical procedures for the reduction of aggression in a residential setting. Mental Retardation, 15, 25-28.

Carr, J. E., & Britton, L. N. (1999). Idiosyncratic id·i·o·syn·cra·sy  
n. pl. id·i·o·syn·cra·sies
1. A structural or behavioral characteristic peculiar to an individual or group.

2. A physiological or temperamental peculiarity.

 effects of noncontingent reinforcement on problematic speech. Behavioral Interventions, 14, 37-43.

Carr, J. E., Coreaty, S., Wilder, D. A., Gaunt gaunt

thin plus obvious diminution in abdominal size, indicative of reduced feed intake leading to reduced gut fill.
, B. T., Dozier Dozier may be:

  • Gwen Dozier, singer
  • James L. Dozier, US Army general
  • James C. Dozier, Medal of Honor Recipient
  • Kimberly Dozier, CBS News correspondent
  • Lamont Dozier, musician
  • Dozier, Alabama, a town in the United States
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Carr, J. E., & LeBlanc, L. A. (in press). Noncontingent reinforcement (NCR) as antecedent ANTECEDENT. Something that goes before. In the construction of laws, agreements, and the like, reference is always to be made to the last antecedent; ad proximun antecedens fiat relatio.  behavior support. In J. K. Luiselli (Ed.), Antecedent intervention: Recent developments in community focused behavior support. Baltimore, MD: Brookes.

Columbus Children's Research Institute (2005, May 09). Slips and falls most frequent cause of bathtub injuries despite adult supervision. Retrieved April 5, 2006, from

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1. The maintenance of one attitude for a long period.
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Piazza, C. C., Hanley, G. P., & Fisher, W. W. (1996). Functional analysis and treatment of cigarette pica. Journal of Applied Behavior Analysis, 29, 437-450.

Thelen, M. H. (1979). Treatment of temper tantrum temper tantrum Pediatrics A prolonged anger reaction in an infant or child, characterized by screaming, kicking, noisy and noisome behavior, or throwing him/her self on the ground to get his/her way from a parent/caretaker/warden. Cf Adult temper tantrum.  behavior by means of noncontingent positive attention. Journal of Clinical Child Psychology, 8, 140.

Vollmer, T. R., Iwata, B. A., Zarcone, J. R., Smith, R. G., & Mazaleski, J. L. (1993). The role of attention in the treatment of attention-maintained self-injurious behavior: Noncontingent reinforcement and differential reinforcement of other behavior. Journal of Applied Behavior Analysis, 26, 9-21.

Voller, T. R., Progar, P. R., Lalli, J. S., Van Camp, C. M., Sierp, B. J., Wright, C. S., Nastasi, J., & Eisenshink, K. J. (1998). Fixed-time schedules attenuate To reduce the force or severity; to lessen a relationship or connection between two objects.

In Criminal Procedure, the relationship between an illegal search and a confession may be sufficiently attenuated as to remove the confession from the protection afforded by the
 extinction-induced phenomena in the treatment of severe aberrant behavior. Journal of Applied Behavior Analysis, 31, 529-542.

Vollmer, T. R., Rindahl, J. E., Roane, H. S., & Marcus, B. A. (1997). Negative side effects Side effects

Effects of a proposed project on other parts of the firm.
 of noncontingent reinforcement. Journal of Applied Behavior Analysis, 30, 161-164.

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Ryan D. Ward and Thomas S. Higbee

Utah State University Utah State University, mainly at Logan; coeducational; land-grant and state supported; chartered 1888, opened 1890. It publishes Utah Science, Western Historical Quarterly, and Western American Literary Journal.  

Correspondence to Thomas S. Higbee, Dept. of Special Ed. and Rehab., Utah State University, 2865 Old Main Hill, Logan, UT 84322-2865; email:
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Author:Ward, Ryan D.; Higbee, Thomas S.
Publication:Education & Treatment of Children
Article Type:Report
Geographic Code:1USA
Date:May 1, 2008
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