JOURNAL OF APPLIED BEHAVIOR ANALYSIS

BEHAVIORAL MOMENTUMJN THE TREATMENT OF NONCOMPLIANCE

F. CHARLES MACE RUTGERS UNIVERSITY

MICHAEL L. HOCK UNIVERSITY OF VERMONT

JOSEPH S. LALLI, BARBARA J. WEST, P-Huup BELFIORE, AND ELIzABETH PINTER LEHIGH UNIVERSrrY

D. KIRBY BROWN LANCASTER-LEBANON INTERMEDIATE UNIT

Behavioral momentum refers to the tendency for behavior to persist following a change in envi- ronmental conditions. The greater the rate of reinforcement, the greater the behavioral momentum. The intervention for noncompliance consisted of issuing a sequence of commands with which the subject was very likely to comply (i.e., high-probability commands) immediately prior to issuing a low-probability command. In each of five experiments, the high-probability command sequence resulted in a "momentum" of compliant responding that persisted when a low-probability request was issued. Results showed the antecedent high-probability command sequence increased compliance and decreased compliance latency and task duration. "Momentum-like" effects were shown to be distinct from experimenter attention and to depend on the contiguity between the high-probability command sequence and the low-probability command. DESCRIPTORS: behavioral momentum, compliance latency, excessive task duration, noncom-

pliance, high-probability command sequence

Noncompliance is one of the most commonly reported behavior problems in developmentally dis- abled populations (Schoen, 1983). In addition to its prevalence, treatment of noncompliance is im- portant because of its covariation with other aber- rant and adaptive behaviors. For example, several studies have demonstrated that increased compli- ance often results in collateral reductions in aggres- sion, disruption, self-injury, and tantrums (e.g., Cataldo, Ward, Russo, Riordan, & Bennett, 1986; Parrish, Cataldo, Kolko, Neef, & Egel, 1986; Rus-

This research was funded in part by a grant from the Pennsylvania Office of Mental Health/Mental Retardation. The authors gratefully acknowledge the support of Richard J. Smith, Timothy Boyer, and Al Deibler of Lehigh County MH/MR that made this work possible.

Experiment 1 and the concepts of applied behavioral mo- mentum and the high-probability command sequence were presented at the 12th annual ABA convention (Hock & Mace, 1986). Experiments 1-5 were presented in a symposium at the 13th annual ABA convention (Mace, 1987).

Reprint requests may be addressed to F. Charles Mace, Graduate School of Applied and Professional Psychology, Rutgers University, Box 819, Piscataway, NewJersey 08854.

so, Cataldo, & Cushing, 1981). Conversely, re- duced noncompliance has been associated with in- creased appropriate behavior (Baer, Rowbury, & Baer, 1973). Thus, intervention to increase com- pliance appears to be an efficient means of im- proving a range of socially important behaviors. A variation of noncompliance is slowness to re-

spond to instructions or complete assigned tasks. Individuals who are excessively slow at completing tasks may receive less reinforcement (e.g., income from vocational tasks) and may incur punitive social responses from peers or staff.

Considerable research has evaluated procedures for increasing compliance and, to some extent, for reducing excessive compliance latency and task du- ration. However, much of this research has been conducted with children (Breiner & Beck, 1984; Fjellstedt & Sulzer-Azaroff, 1973; Forehand & McMahon, 1981). Procedures commonly used to increase compliance indude time-out (e.g., Parrish et al., 1986) and guided compliance (e.g., Neef, Shafer, Egel, Cataldo, & Parrish, 1983). However,

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1988,211,123-141 NUMBER2 (summER 1988)

F. CHARLES MACE et al.

a potential liability of these procedures is that they often require physical contact with a client to achieve treatment integrity, which for large, uncooperative, or aggressive clients may be ill-advised. Alterna- tively, the effectiveness of differential reinforcement of compliant behavior depends on reinforcement for compliant responses being rich relative to re- inforcement produced by noncompliant or daw- dling behavior (cf. Ayllon, Garber, & Pisor, 1976; Cuvo, 1976; Holt, 1971). Unless a more powerful reinforcer or richer schedule can be applied to com- pliant behavior compared to the reinforcer and schedule maintaining noncompliance, differential reinforcement may not have the desired effect and punishment-based alternatives may need to be con- sidered (Myerson & Hale, 1984).

Alternative approaches to increasing compliance with developmentally disabled adults may be de- rived from consideration of advances in basic op- erant research (e.g., Deitz, 1978; Hayes, Rincover, & Solnick, 1980; Michael, 1980; Pierce & Epling, 1980). For example, Nevin has discussed the re- lationship between response strength and rate of reinforcement (see Nevin, 1974, 1979, for re- views). Behavior maintained at steady states by interval or ratio schedules of reinforcement has been shown to persist over time following a change in reinforcement conditions (de Villiers, 1977; Nevin, 1979; Zeiler, 1977). This resistance to change in the face of altered contingencies has been referred to as "response strength" (Herrnstein, 1970; Nev- in, 1979). Response strength may be relatively low when response patterns change readily or relatively high when response rates are slow to change under modified conditions. In general, behavior controlled by a multiple schedule will be more resistant to change during the schedule component that has a comparatively higher rate of reinforcement. That is, a relatively higher rate of reinforcement will result in relatively greater resistance to change or greater response strength.

Nevin, Mandell, and Atak (1983) suggested a parallel between a behavior's resistance to change and the momentum of objects in motion as de- scribed by Newton's first law of motion. They argued that it may be worthwhile to consider be-

havior at possessing the property of momentum. Accordingly, behavioral momentum can be ana- lyzed in terms analogous to the product of mass and velocity in classical physics (Nevin et al., 1983, p. 49). Behavioral mass was considered formally analogous to response strength and behavioral ve- locity as corresponding to response rate. Nevin et al. demonstrated that behavior controlled by a two- component multiple schedule procedure was more resistant to change in the component with a rela- tively higher rate of reinforcement when reinforce- ment was provided noncontingently, or when all reinforcement was discontinued. Thus, factors that influence rate of reinforcement may be expected to affect a behavior's resistance to change.

Consideration of Nevin et al.'s (1983) work on behavioral momentum prompted us to develop a novel intervention for noncompliance and excessive compliance latency and task duration. This pro- cedure, referred to as the high-probability com- mand sequence, indirectly manipulates rate of re- inforcement to establish what appears to be a "momentum" ofcompliant behavior that may per- sist when subjects are asked to perform a task with a low probability of compliance. Our objectives in the following series of experiments were (a) to eval- uate the effectiveness of the high-probability com- mand sequence in increasing compliance to "do" and "don't" commands (Neef et al., 1983) (Ex- periment 1), (b) to conduct preliminary investi- gations regarding the appropriateness of the be- havioral momentum analogy (Experiments 2 and 3), and (c) to evaluate the generality of the pro- cedure to reduce excessive compliance latency and task duration (Experiments 4 and 5).

EXPERIMENT 1

METHOD Subject and Setting

Bart, a 36-year-old man with severe mental re- tardation (IQ = 42), served as the subject in this experiment. Bart had resided in large, state-oper- ated institutions for most of his life and had a long history of noncompliance and aggression. Bart's

124

BEHAVIORAL MOMENTUM

large physical stature (height 6'1", weight 200 lb) contributed to the severity of his noncompliance and aggression. In his first community placement, these behaviors eventually resulted in his recom-

mitment to a private institution.

At the time of the present experiment, Bart had lived in a university-affiliated group home for ap-

proximately 18 months. The program was behav- ior-analytic in nature and was operated by univer- sity graduate students and faculty. Typical staffing patterns consisted oftwo graduate students working with six adults with moderate to severe mental retardation. After 6 months in this program, Bart became increasingly noncompliant and aggressive. A structured self-management program consisting of positive reinforcement for completion of house jobs and personal hygiene, without aggressive in- cidents, was effective only for periods of 2 to 3 months.

Sessions were conducted in the living room (5 m by 4 m), family room (3.5 m by 3 m), and kitchen (5 m by 4 m) of the home. An experi- menter, one or two data collectors, and zero to two

other clients were present during these sessions. Interactions between staff and other dients were

minimal; client-clent interactions were unrestrict-

ed. Because of the applied nature of the research, the subject was allowed free movement in these rooms to assess experimental effects under natural conditions.

Response Definitions, Measurement, and Interobserver Agreement

The principal dependent measure was the per-

centage of compliance to low-probability (low-p) "do" and "don't" commands. In Experiment 1, low-p commands were instructions or requests is- sued by the experimenter to the subject with which, in the experimenter's experience, the subject was

unlikely to comply. (In the remaining four exper-

iments, the probability value of both low-p and high-p commands was empirically determined.) Examples of low-p "do" and "don't" commands are "Bart, please put your lunch box away" and "Bart, please don't leave your lunch box on the table." Commands called for performance of sim-

ple tasks that could be completed within 30 to 60 s (i.e., "do" commands) or discontinuation of an undesirable behavior or condition (i.e., "don't" commands). Command compliance was defined as the subject initiating the response called for by the command within 10 s of the stated command and eventually completing the requested response(s).

The independent variable in this experiment was a sequence of high-probability (high-p) commands that was issued prior to a low-p command. High-p commands were instructions or requests with which the subject had a history of complying. These com- mands were always stated as a "do" request and are exemplified by the following: "Give me five, Bart," "Come here and give me a hug," and "Show me your pipe (or wallet, notebook, etc.), Bart." The mean percentage compliance to high-p com- mands during the entire experiment was 98%. Two trained observers recorded (a) experimenter

commands or requests directed to the subject for low-p and high-p behaviors, (b) compliance to "do" and "don't" low-p commands, and (c) compliance to high-p commands. A count of all responses was made during continuous 10-s intervals. A per- centage compliance measure was derived for each session by dividing the number of compliant re- sponses (of a given dass) by the number of exper- imenter requests for responses (of the same dass) and multiplying by 100. Observers stood within 2 to 5 m of the experimenter and subject but did not speak or make eye contact with the subject.

The second observer independently collected in- terobserver agreement data from a position no closer than 2.5 m from the primary observer during an average of 66% of the sessions across all phases and conditions of the experiment. For the first three experiments, total, occurrence, and nonoccurrence agreement were calculated on a point-by-point basis within all intervals per session (Page & Iwata, 1986). Table 1 presents the mean and range of interob- server agreement values for the dependent and in- dependent variables for all experiments.

Procedures Baseline. During each baseline session, the ex-

perimenter stood or sat within 1 to 2 m of the

F. CHARLES MACE et al.

Table 1 Interobserver Agreement: Mean and Range Percentages for Total Agreement (TA), Occurrence Agreement (OA),

Nonoccurrence Agreement (NOA), and Agreement (A) within ±1 s across the Dependent and Independent Variables of Experiments 1 through 5

Experiment 1 Experiment 2

TA OA NOA TA

Dependent variables Compliance with "do" commands 99 99 94 99.5

(93-100) (93-100) (63-100) (95-100) Compliance with "don't" commands 97 79 96

(92-100) (53-100) (91-100) Compliance with "do" commands 99.1

(during attention control) (97-100) Latency to initiate task Minutes to complete task

Independent variables Compliance with high-p commands 93 85 89 94.7

(83-98) (71-94) (77-97) (75-100) Occurrence of high-p 93 85 89 96.4

(83-98) (71-94) (77-97) (87-100) Occurrence of attention – 98.4

(97-100) Occurrence of 5-s IPT

Occurrence of 20-s IPT

Occurrence of prompts Occurrence of contingency statement Delivery of reinforcement

subject. The primary data collector prompted the experimenter to issue a command to the subject on a fixed-time (FI) 1-min schedule. The experi- menter made eye contact with the subject and issued a low-p command or request to Bart in a pleasant tone of voice. Low-p commands were selected at random from a pool of 20 low-p commands or, in the case of many low-p "don't" commands, were chosen on the basis of the subject's behavior (e.g., "Bart, don't put your feet on the coffee table"). If the subject satisfied the definition of command compliance, the experimenter provided immediate descriptive praise (e.g., "That's good Bart, thanks for putting your lunch box away"). Descriptive praise was used as a consequence for compliance for subjects in all five experiments because, in the experimenters' experience, praise appeared to be an effective reinforcer for these individuals. "Do" and "don't" command sessions differed only in the dass

of commands issued to the subject (i.e., either all "do" or all "don't" low-p commands).

Psychotropic intervention-Haldol. On Day 7 of the experiment, Bart's psychiatrist prescribed 10 mg of Haldol b.i.d. to control his aggressive be- havior. This represented a return-to-Haldol inter- vention, which Bart had experienced during the past 7 years, after a 6-week period of medication withdrawal. Baseline procedures remained in effect. Psychotropic intervention continued during all sub- sequent phases of the experiment.

High-probability command sequence. This condition was identical to the baseline procedures except that each low-p command was preceded by a sequence of high-probability (high-p) commands. The high-p command sequence consisted of the experimenter issuing a series of three or four high-p commands or requests to the subject immediately preceding presentation of the low-p command.

126

BEHAVIORAL MOMENTUM

Table 1 (Continued)

127

Experiment 2 Experiment 3 Experiment 4 Experiment 5 OA NOA TA OA NOA TA A ± I s TA A ± I s

96.7 99.6 99 98.7 97 – (69-100) (96-100) (92-100) (92-100) (80-100) – – 99 97 97 –

(93-100) (88-100) (82-100) 90.9 99.4 – – 100

(71-100) (97-100) 100

-_— – – – – 100

95 97.1 95 95 93 100 – 100 (77-100) (86-100) (90-100) (88-100) (79-100)

95.4 97.1 96 96 94 100 100 – (82-100) (92-100) (91-100) (92-100) (87-100)

94 98.6 100 – (88-100) (95-100)

– – 99 96 99 –

(98-100) (88-100) (96-100) 99 95 99 – –

(98-100) (82-100) (97-100) – – – — – – 100 –

-_— — – 100 100

High-p commands were issued at 10-s intervals (i.e., the interval between completion of a high-p task and the next high-p command).

Experimental Design The experimental conditions described above were

presented to the subject during two 1 5-min sessions daily that were separated by a 15- to 30-min free time period. Because "do" and "don't" commands have been shown to be members of different stim- ulus dasses (Neef et al., 1983), sessions with either all "do" commands or all "don't" commands were alternated in a multielement design (Sidman, 1960). The order in which "do" and "don't" command sessions were conducted was determined randomly each day. In addition, the independent variable was alternately applied and withdrawn during "do" and "don't" command sessions in the context of a re- versal design (Sidman, 1960).

REsuLsT Figure one represents Bart's percentage of com-

pliance to low-p commands during "do" and "don't" command sessions across all phases of the experiment. During baseline, Bart's compliance to low-p requests during "do" sessions averaged 47% and during "don't" sessions 53.5%. With the ad- dition of psychotropic medication, mean compli- ance to "do" commands was 68% versus 53.5% for "don't" commands.

During Phase 3, application of the high-p com- mand sequence prior to each "don't" command resulted in an increase in mean compliance to 87.5%. Compliance to "do" commands, which remained under baseline conditions, averaged only 61%. In Phase 4, the pattern of compliance reversed with "do" command sessions increasing to a mean of 90.5% following application of the high-p com-

128 F. CHARLES MACE et al.

High Probability Command Sequence Preceding

A Low Probability Command

A

00) 100

z < 80 -lu a.

>- 60 c –

u K5 w m 40

w 0 so 31 0'"Jo CO _j

Baseline

"Don't"

"Do"

5

Psychotropic Applied to Applied to Applied to Applied to

Intervention-Holdol "Don't" Commonds 'Do" Commonds 'Don't"Commands 'Do" a"Don't" Commands

L~~~~ WI

>I KY 10 15 20 25 30 35

SESSIONS

Figure 1. Bart's percentage compliance to low-probability "do" and "don't" commands under baseline and psychotropic intervention conditions, and alternate application and withdrawal of the high-probability command sequence.

mand sequence. "Don't" command compliance re-

turned to low levels during this period (M = 44%). In the fifth phase, compliance to "don't" com-

mands returned to high levels when low-p com-

mands were preceded by a series of compliant re-

sponses (M = 91%). Compliance to "do" commands, which were not preceded by the high-p command sequence, averaged only 56%. In the final experimental phase, use of the high-p com-

mand sequence resulted in high levels ofcompliance to both "do" and "don't" commands. Mean com-

pliance ranged from 87% to 97% for "do" com-

mand sessions (M = 93%) and 85% to 97% for "don't" command sessions (M = 90%).

DISCUSSION

This experiment demonstrated the effectiveness of preceding a low-probability command with a

sequence of high-probability commands in the treatment of noncompliance. Establishing a pattern

ofcompliant responding by the subject immediately prior to the issuance of a low-p request resulted in increases in the subject's compliance. Our objective in the second experiment was to assess the subject generality of the high-p procedure and to examine possible effects of positive attention alone on com-

pliance.

EXPERIMENT 2

MEHOD

Subject and Setting The subject of the second experiment was Ned,

a 44-year-old severely retarded (IQ = 21) male with Down Syndrome. Ned had lived in institu- tions for most of his life. When asked to perform a task, Ned typically shook his head "no" and looked away. Occasionally, he would throw items, curse, spit, hit others, or lie on the floor when such commands were issued. The setting for the study was the same house as

in Experiment 1. During the first four phases of the experiment, baseline and treatment high-p com- mand sessions were conducted in the kitchen. At- tention control sessions were held in the subject's second floor bedroom (4 m by 3.5 m). Persons present and their interactions during the sessions were similar to those in the first study.

Response Definitions, Measurement, and Interobserver Agreement

Ned primarily did not comply with "do" re- quests. The procedure for identifying commands to which the subject had a low probability of com- plying consisted of the experimenter approaching

I II

BEHAVIORAL MOMENTUM

Ned and asking him to perform each of 25 tasks on separate occasions. Ten separate trials were con-

ducted for each of the 25 tasks; those commands that were complied with four or fewer times in 10

trials were designated as low-p commands. This procedure resulted in a pool of 15 low-p "do" commands that were used in the experiment. A similar procedure used with high-probability com- mands (i.e., at least 80% compliance) resulted in the following high-p command sequence: (a) "Ned, give me five," (b) "Give me a bump" (i.e., the experimenter and subject bumped hips in a dancing motion), and (c) "Ned, show me your radio."

The definition of command compliance and the data collection procedures for the primary and sec-

ondary observers were identical to those in Exper- iment 1 (see Table 1 for interobserver agreement values).

Procedures Baseline. The actions of the experimenter and

data collectors during this condition were virtually identical to those described for the baseline con-

dition for Experiment 1. High-probability command sequence. The pre-

sentation of the high-p command sequence and the experimenter's response to compliance were iden- tical to the procedures used during this condition in the first experiment.

Attention control. This condition was designed to provide experimenter attention prior to issuance

of a low-p command without providing specific discriminative stimuli for behaviors presumably maintained by high rates of reinforcement. On an

FT 1-min schedule, the experimenter sat or stood within 1 to 2 m of the subject and directed a

sequence of three or four neutral or positive com-

ments to the subject. Comments were randomly selected from a pool of 2 5 statements. The interval between comments ranged from 10 to 15 s. Ex- amples of these comments included "Ned, that's a nice shirt you're wearing," "We're going bowling this afternoon," and "I'm going to visit my parents

this weekend." Within 10 s of the last comment, the experimenter issued a randomly selected low-p command to the subject. Compliance to low-p com-

mands resulted in descriptive praise on a continuous reinforcement (CRF) schedule. Experimental Design

The experimental procedures were presented dai- ly during two 1 5-min sessions separated by a 15- to 30-min free time period. An ongoing attention control condition was alternated with either the baseline or the high-p command sequence condition in a multielement design. The order in which con- ditions were conducted was determined randomly each day. The effects of the high-p command se- quence were evaluated with an A-B-A-B reversal design. In the final phase of the experiment, the settings in which the high-p command sequence condition and the attention control condition were conducted were reversed to control for possible ef- fects of setting-specific commands.

REsuLTs Figure 2 depicts Ned's compliance to low-p

commands during all baseline, high-p command sequence, and attention control conditions. In the initial baseline phase, issuing low-p commands without a preceding high-p command sequence re- sulted in a mean compliance of 26%. When ex- perimenter attention preceded each low-p com- mand, compliant behavior was similar to baseline (M = 35%). During Phase 2, application of the high-p command sequence effected an increase in mean compliant responses to 73%. Compliance during the attention control sessions remained es- sentially unchanged from the previous phase (M = 38%). A return to baseline condition in the third phase

produced an immediate decrease in the subject's percentage compliance (M = 39%). Comparable levels of compliance (M = 43%) continued during the subsequent attention control condition. In the fourth phase, high levels of compliance occurred when the high-p command sequence was reinstated (M = 84%). Average percentage compliance in- creased slightly during the ongoing attention control condition (M = 51%). Finally, the setting reversal had little effect on the subject's pattern of compli- ance during the high-p command sequence (M =

79%) and attention control conditions (M = 47%).

F. CHARLES MACE et al.

No High- P Command Sequence Preceding A

o CX Low – P Command I .equence Qequec I ze IiI

10 I Reversal

z G 800 I

IY3 0 ~ Attention Preceding A 0- 0-ij

C-40W/ o Low-P Command

Cr 0 w/o Attention li W 0 '

5 10 15 20 25 30

SESSIONS Figure 2. Ned's percentage compliance to low-probability commands during the attention control condition and alternate

application and withdrawal of the high-probability command sequence. In the final experimental phase, the settings in which the attention control and high-p sequence were conducted were reversed.

DISCUSSION Results of the second experiment support the

subject generality of the effects produced by the high-p command sequence inasmuch as the effects for Ned and Bart were similar. A second important finding was that experimenter attention was not itself sufficient to occasion compliance to low-p requests. That is, experimenter comments presented in the same manner as high-p commands failed to influence the probability of subject compliance. This finding suggests that presentation of discriminative stimuli for high-probability behaviors is critical to the momentum-like effects observed.

In the third experiment, we investigated another parameter of the high-p command procedure that may determine its effectiveness as an applied pro- cedure and further examines the value of the be- havioral momentum analogy. Nevin et al. (1983) found that resistance to change or behavioral mo- mentum was directly related to rate of reinforce- ment. The higher the relative rate of reinforcement, the greater the resistance to change. Therefore, it may be logical to predict that momentum-like ef- fects will decrease with an increase in the interval between the last high-p command in the sequence (or between any high-p commands in the sequence)

and the statement of the low-p command. Increas- ing this interval presumably has the effect of de- creasing rate ofreinforcement which, in turn, should decrease behavioral momentum.

EXPERIMENT 3

METHOD

Subject and Setting The subject and setting in which experimental

sessions were conducted were identical to those de- scribed in Experiment 1. Bart continued to take 10 mg of Haldol b.i.d. for the duration of the study. This experiment was conducted 1 month after completion of the first study.

Response Definitions, Measurement, and Interobserver Agreement

As in Experiment 1, the principal dependent measure in the third experiment was the percentage compliance to low-p "do" and "don't" commands. The procedure described in Experiment 2 to iden- tify low- and high-probability commands was used to define a pool of 15 low-p "do" commands, 10 low-p "don't" commands, and seven high-p "do"

130

BEHAVIORAL MOMENTUM

High Probability Command Sequence Preceding

A Low Probability Command A

20-s IPT a"Do" 20-s IPT"Don't 5-s IPT "Donti 5-s IPT "Do"

to"Don't"l

'~~ ~~I

5

20-s IPT "Do" 120-sIPT"Don't"20-s IPT "Do" | 5-s IPT 5-s IPT "Don't" 5-s IPT "Do" 5-s IPT" Don't Do a &qu

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