1990, NUMBER2 (summer 1990)

Transcription

1 JOURNAL OF APPLIED BEHAVIOR ANALYSIS 199, NUMBER2 (summer 199) USING ABERRANT BEHAVIORS AS REINFORCERS FOR AUTISTIC CHILDREN MARJORIE H. CHARLOP CLAREMONT MCKENNA COLLEGE PATEICIA F. KuRrz CLAREMONT GRADUATE SCHOOL AND FRAN GREENBERG CASEY THE GEORGE WASHINGTON UNIVERSITY In a series of experiments, we assessed the effiay of using autisti hildren's aberrant behaviors as reinforers to inrease their orret task responding. In Experiment 1, reinforer onditions of stereotypy, food, and varied (food or stereotypy) were ompared. In Experiment 2, the onditions were delayed eholalia, food, and varied (food or delayed eholali, and in Experiment 3, perseverative behavior was ompared with stereotypy and food as potential reinforers. A multielement design was used for all omparisons, and side-effet measures were reorded during and after teahing sessions as well as at home. Results indiated that, in general, task performane was highest when brief opportunities to engage in aberrant behaviors were provided as reinforers. Edibles were assoiated with the lowest performane. Furthermore, no negative side effets (e.g., an inrease in aberrant behaviors) ourred. The results are disussed in terms of suggesting a more pragmati treatment approah by addressing the ontingent use of autisti hildren's aberrant behaviors as reinforers. DESCRIPTORS: autism, aberrant behaviors, stereotypy, delayed eholalia, perseverative behavior Identifying reinforers for autisti hildren has been problemati in that these hildren often do not respond to stimuli that interest other hildren (e.g., toys) or to soial reinforers (e.g., praise, smiles, or approval). Although primary (food) reinforers an be effetive (e.g., Egel, 1981), various problems have been assoiated with their use, induding rapid satiation and diffiulties in administration. Premak (1959) demonstrated that a highly preferred (i.e., high-frequeny) ativity an be used to This researh was supported in part by Researh Grant 4176 from the National Institute of Mental Health and by NIH Biomedial Researh Support Grant 257RR Experiment 3 of this investigation was a thesis submitted by the seond author to Claremont Graduate Shool in partial fulfillment for a MA degree in psyhology. The authors aknowledge Karen Ball, Jane Trasoweh, Catherine Fairy, Dee Dee Eastis, James Gonzalez, Chris Kimball, Karen Laski, Len Levin, Janie Milstein, and Jerry Silliman for their assistane in data olletion and reliability. Reprints may be obtained from Marjorie H. Charlop, Psyhology Department, Claremont MKenna College, Claremont, California reinfore a less preferred (i.e., low-frequeny) response. Applying this priniple with autisti hildren, their most preferred or frequent ativities are often aberrant behaviors suh as stereotypy (Lovaas, Koegel, Simmons, & Long, 1972). Aordingly, stereotypy, albeit inappropriate behavior, may effetively funtion as a reinforer. Indeed, results from several studies have provided initial support for this notion (Hung, 1978; Sugai & White, 1986; Wolery, Kirk, & Gast, 1985). Importantly, Wolery et al. (1985) reported no negative side effets in that no inreases in overall frequeny of stereotypy ourred as a result of providing brief, ontrolled periods of stereotypy ontingent upon orret response. Although these studies are quite promising, additional researh is needed, beause only a few hildren have partiipated in previous studies and a diret omparison of edibles and stereotypy as reinforers has not been onduted. The possibility that other high-frequeny behaviors displayed by autisti hildren may also have

2 164 MARJORIE H. CHARLOP et al. reinforing properties merits investigation. For example, many verbal autisti hildren exhibit delayed eholalia, the repetition of previously heard utteranes (Fay & Shuler, 198; Riks & Wing, 1975). These hildren often repeat speifi words or phrases, leading some researhers to suggest that partiular forms of delayed eholalia may possess reinforing funtions (e.g., Lovaas, Varni, Koegel, & Lorsh, 1977; Prizant & Rydell, 1984). Similarly, autisti hildren's perseverations with speifi objets is another high-frequeny behavior that may have reinforing properties (Epstein, Taubman, & Lovaas, 1985; Lovaas, Newsom, & Hikman, 1987). The hildren's repeated display of delayed eholalia and perseverative behavior ontrasts sharply with their general unresponsiveness to their environment. Thus, it seems likely that these behaviors may also serve as reinforers. During the past 5 years, we onduted a series of three experiments evaluating the effiay of using aberrant behaviors (stereotypy, delayed eholalia, and perseverative behavior) as potential reinforers for autisti hildren. In Experiment 1, we extended previous researh on using stereotypy as a potential reinforer by diretly omparing its use as a reinforer with both food and onditions of varied onsequenes (food or stereotypy) in a multielement format. We induded the varied onsequene ondition beause Egel (1981) suggested that presentation of two or more reinforers in a varied format may maximize reinforer effetiveness. In Experiment 2, we ompared the use of delayed eholalia as a potential reinforer with both food and varied onsequenes (delayed eholalia or food). Finally, in Experiment 3, we ompared the use of perseverative behavior as a potential reinforer with stereotypy and food. In all three experiments, assessments of potential negative side effets (i.e., an inrease in the overall frequeny of the aberrant behaviors) were onduted in a more omprehensive manner than in previous investigations. Subjets by GENERAL METHOD All partiipants had been diagnosed as autisti two independent agenies aording to DSM- III riteria (Amerian Psyhiatri Assoiation, 198). All hildren had attended biweekly therapy sessions at an after-shool behavior modifiation program for autisti hildren for a minimum of 6 months. Children were seleted to partiipate in the experiments based on lassroom teahers', parents', and therapists' reports that they appeared unmotivated to learn and often engaged in aberrant and off-task behaviors. Setting and Tasks Experimental sessions were onduted in a work room at the hildren's after-shool program. In this room were two hild-size hairs, a table, a large storage abinet, and various toys and eduational stimuli. The work room was onneted to a large observation room by a one-way mirror, whih was used by reliability observers during experimental sessions. Three tasks (e.g., naming body parts, use of prepositions, and pronouns) were seleted from eah hild's aademi urriulum for presentation during experimental sessions. Eah task had been part of the hild's regular therapy sessions for several months but had proven quite diffiult to learn. Design A multielement design was used to assess the differential effetiveness of three potential reinforers: ( food, (b) aberrant behavior (either stereotypy, delayed eholalia, or perseverative behavior, depending on the experiment), and () varied onsequenes (food or aberrant behavior). For Experiment 3, however, the onsequene onditions onsisted of stereotypy, food, and perseverative behavior, and a varied onsequene ondition was not presented. No experimental ondition was presented more than three times onseutively, and the total number of sessions of eah ondition was varied to assess any hanges in performane over time. General Proedure Baseline. Eah hild was presented with a typial 15-min work session during whih the seleted tasks were presented as desribed below in the foodas-onsequene ondition. For Experiments 1 and

3 ABERRANT BEHAVIORS 2, baseline onsisted of one or two probes per week olleted over a 6- to 8-month period before the multielement analyses began. Baseline for Experiment 3 was presented during the weeks immediately preeding the multielement analysis. Experimental onditions. Two 15-min experimental sessions were presented weekly to eah hild, usually 2 to 5 days apart. were designed to simulate as dosely as possible typial work sessions in the after-shool program. The experimenter sat faing the hild and presented trials when the hild was sitting attentively and providing eye ontat. The order of presentation of tasks within a session was randomly varied aross sessions. Throughout all onditions, after eah orret response, the experimenter immediately provided both praise (e.g., "That's right! Good boy.") and a onsequene orresponding to the partiular reinforer ondition for that session. After an inorret response or failure to respond within 5 s, a verbal "No" was presented. After two onseutive inorret trials, the experimenter provided a orretion trial (e.g., requested "Give me blue blok" and pointed to the blok), verbal praise, and a reinforer ontingent upon orret response. Corretion trials were not induded in the data analysis. Following eah trial, the experimenter reorded the hild's response (orret or inorret) on a data sheet. During and after eah session, the ourrenes of the aberrant behavior, stereotypy, and off-task behavior were reorded for eah hild. Consequene Conditions The speifi onsequenes used in the following onditions were determined to be desirable for eah hild based on diret observations and parent and therapist reports. Food as a onsequene. During this ondition, a preferred food (e.g., small piee of hoolate, ereal, or ookie) from a variety tray was presented ontingent upon eah orret response. Typially, the hild was asked to hoose from the available treats. Aberrant behavior as a onsequene. In this ondition, the hild was allowed, and sometimes prompted, to engage in speifi aberrant behavior for 3 to 5 s ontingent upon orret response. In Experiment 1, the aberrant behavior onsisted of a speifi type of stereotypy; in Experiment 2, the aberrant behavior was delayed eholalia; and in Experiment 3, two onditions of aberrant behaviors, perseverative behavior and stereotypy, were evaluated. For example, in Experiment 1, Child 1 was allowed to posture his hand in front of his eyes for a few seonds after eah orret answer. On the first few trials, however, it was neessary for the experimenter to enourage the hild verbally to engage in stereotypy (e.g., "You an look at your fingers now. "). Varied onsequenes. During this ondition, ontingent upon orret response, the hild was permitted to hoose either a food treat or the opportunity to engage in 3 to 5 s of a speifi aberrant behavior. No more than three onsequenes of one kind were presented onseutively; if the hild ontinually requested a stereotypi behavior, the experimenter said, "Let's eat something now, and you an later." Experimental session observation. During eah session, a primary observer in the observation room reorded eah ourrene of the aberrant behavior (when not used as a onsequene), stereotypy, and off-task behaviors using a 1-s partial interval soring proedure. Prior to the study, observers were trained in the use of this proedure by jointly observing, identifying, and reording the hild's defined behaviors with the experimenter until at least 9% interobserver agreement was demonstrated. A prereorded tape signaling the intervals was played throughout the session, and the observers marked ourrenes on preoded data sheets. Operational definitions for eah hild's observed behaviors were determined prior to the study based on parent and therapist report and by observations of eah hild during free-play and regular therapy sessions (see Tables 1, 2, and 3, for Experiments 1, 2, and 3, respetively). Postexperimental session observation. Following eah 15-min experimental session, a 15-min postsession observation was onduted in whih behaviors were observed and reorded in the same manner. Two postsession observation settings were used for Experiments 1 and 2: ( a work session, in whih the hild worked with another therapist

4 166 MARJORIE H. CHARLOP et al. Table 1 Stereotypy and Off-task Behaviors Displayed by Subjets in Experiment 1 Child 1 Child 2 Child 3 Child 4 Stereotypy waving hand flapping objets rossing eyes flapping hands making noises tapping objets flapping hands suking thumb rubbing objets roking in hair roking in hair toy in mouth tapping objets flapping objets shirt in mouth snapping fingers high-pith sream Off-task out of seat aggression nonompliane out of seat behavior lean hair bak out of seat laughing lean on therapist lap rying tap hair feet on hair giggling throw toy bite in a typial session in the therapy room, or (b) an unstrutured free-play session, in whih the hild remained in the observation room where toys were available. In Experiment 3, no distintion between work and freeplay was made, beause there appeared to be no unexpeted differenes between the work and play environments. Reliability Reliability was olleted for a minimum of 33% of all baseline and experimental sessions. Interobserver reliability was alulated by dividing the number of agreements by the total number of agreements plus disagreements, then multiplying by 1. Interobserver reliability for side-effet measures of aberrant behavior, stereotypy, and off-task behavior during and after experimental sessions was also olleted for a minimum of 33% of eah hild's total sessions. Interobserver agreement was alulated by dividing the total number of agreements for ourrene and nonourrene by the total number of agreements plus disagreements, and then multiplying by 1. EXPERIMENT 1 METHOD Subjets Four male autisti hildren partiipated in Experiment 1. Child 1 was a 6.3-year-old boy (mental age was untestable) who frequently engaged in tantrums, aggression, and immediate and delayed eholalia. Child 1 also displayed high frequenies of stereotypy (e.g., posturing hand in front of eyes, snapping fingers, making repetitive voal noises). He rarely spoke spontaneously and only oasionally used three-word sentenes (e.g., "I want ookie."). Child 2 (hronologial age, 7.6 years; mental age, 2.9 years) was verbal but often exhibited disruptive behaviors (e.g., nonompliane, rying, aggression) when a diffiult task was presented. Additionally, Child 2 frequently engaged in stereotypi behavior (e.g., waving thumb and index fingers in front of eyes, repetitively drawing hek marks) and delayed eholalia. Child 3 (hronologial age, 8.5 years; mental age, 4.2 years) was verbal but often nonompliant in learning situations. He also exhibited stereotypi behaviors of rossing eyes and flipping the pages of a telephone book, off-task behavior suh as inappropriate bursts of laughter, and frequent ritualisti behavior (e.g., lining up hairs in a speifi pattern). In ontrast to the other hildren, Child 4 (hronologial age, 7. years; mental age, 3.4 years) had quite limited and poorly artiulated speeh. This hild frequently engaged in nonompliane, tantrums, and aggression (e.g., pinhing, biting) during the learning situation. Child 4 also exhibited high frequenies of stereotypy, inluding sniffing objets and persons and mouthing or biting objets.

5 ABERRANT BEHAVIORS 167 Table 2 Stereotypy, Off-task Behaviors, and Delayed Eholalia Displayed by Subjets in Experiment 2 Child 1 Child 2 Child 3 Stereotypy rossing eyes tapping objets arhing hands flapping hands flapping hands flapping objets biting hand tapping objets srathing tapping objets rubbing fingers on legs Off-task laughing yelling giggling behavior nonompliane aggression nonompliane yelling out of seat laughing nonompliane blowing on therapist fae Delayed "Ding! ding! ding! "Red red red" "What a mess" eholalia You win again!" "Eat your beef stew!" "Daddy says get out of here" "Math Game 83" "It doesn't stop at the eight, "Don't be silly" it stops at the nine" "No laughing" "C6mo esta, Senor?" Tasks pronouns ("Whose nose is this?"), what's missing Tasks seleted for Child 1 were three disrimi- game (reall whih of three objets was removed nation tasks ofsame/different (i.e., "Give me same" from the set), and immediate reall of previous or "Give me different" in sets of three objets), ations ("Touh head, tummy, and nose-what reeptive pronouns ("Touh your nose."; "Touh did you just do?"). Tasks seleted for Child 3 were my nose."), and prepositions ("Put in box."; "Put expressive pronouns, what's missing, and disrimnext to box."). For Child 2, tasks were expressive ination of before and after onepts (experimenter Table 3 Stereotypy, Off-task Behaviors, and Perseverative Behaviors Displayed by Subjets in Experiment 3 Child 1 Child 2 Child 3 Stereotypy tapping tikling self arhing hands hand posturing swinging feet hand posturing arm posturing masturbating stiking tongue out body roking swinging feet turning head rubbing legs faial grimae rubbing pants repetitive finger or shoulder playing with hair movements staring at hand or fist Off-task out of seat nonompliane out of seat behavior rying oppositional arguing laughing laughing omplaining lean hair bak lean hair bak squirm in hair whining Perseverative Humpty Dumpty leaves Best Produts atalog behavior See-N-Say 9 trees Honda ar advertising booklet plasti farm animals (ow, pig, horse, frog, and duk) atus

6 168 MARJORIE H. CHARLOP et al. Table 4 Interobserver Agreement (%) for Experiments 1, 2, and 3 (O = ourrene; N = nonourrene) Experiment 1 Stereotypy and Off-task N Child Child Child Off-task Stereotypy behavior Aggression O N N N Child Parent Range, 84-1 Experiment 2 Stereotypy and Off-task Delayed eholalia N N Child Child Child Parent Range, 78-1 Experiment 3 Stereotypy Off-task Perseverative O N N N Child Child Child ParentI Parent Parent Range, 75-1 touhes three objets, then asks, "What did I touh before/after?"). For Child 4, tasks were reeptive pronouns, olor disriminations ("Give me red blok."), and a label/loation task (e.g., "What's on the table?"). Proedure Eah hild was presented with the three onsequene onditions in a multielement fashion. During onditions in whih stereotypy was assessed as a onsequene, potential reinforers for the hildren were posturing hand in front of eyes for Child 1, tapping a toy three or four times with index finger for Child 2, flipping pages of a telephone book for Child 3, and sniffing fruit-sented drawing markers for Child 4. Additional analyses for Child 4. To permit a more detailed analysis of possible hanges in ourrene of stereotypy as a funtion of using a speifi response as a reinforer, additional data were olleted for Child 4. Aggression (pinhing, grabbing, biting, and throwing objets) was reorded separately from off-task behavior, beause aggression was a major onern in Child 4's treatment program. Also, the duration of Child 4's postsession observation period was extended from 15 to 3 min, with free-play and work sessions ombined, to assess ourrene of stereotypy over a more extended period of time. Finally, to assess the possible side effet of an inrease in stereotypy in a nontreatment setting, Child 4's mother reorded the frequeny of ourrene of stereotypi behaviors at home both prior to and throughout the study. (This parent previously had been trained in data olletion.) Due to Child 4's high frequeny of stereotypy, frequeny data were olleted daily during 5-min observation periods eah hour (e.g., after shool, in the evenings, and on weekends). Child 4 was hosen for the additional analyses beause he was the last partiipant in this study. Reliability In addition to interobserver agreement for orret and inorret task responses and ourrene and nonourrene of inappropriate behaviors for the side-effet data, six reliability heks between Child 4's mother and the experimenter were taken throughout the study. Cheks onsisted of observing Child 4 during six 5-min unstrutured freeplay sessions at the after-shool program and reording frequeny of ourrene of stereotypi behaviors. Interobserver agreement was alulated by dividing the total number of agreements by the total number of agreements plus disagreements and multiplying by 1. Average interobserver reliability for task performane was 1%, 1%, 98%, and 95% for Chil-

7 ABERRANT BEHAVIORS 169 dren 1, 2, 3, and 4, respetively. For ourrene of stereotypy and off-task behavior, mean interobserver reliabilities for ourrene and nonourrene are provided in Table 4. REsuLTS AND DISCUSSION The hildren's orret task performane is presented in Figure 1; their average baseline performanes on these tasks are depited by the horizontal lines. Baseline probes for Child 1 averaged 5% orret (range, 4%-6%) for a 6-month period, 6% (range, 43%-65%) for Child 2 over a 6-month period, 5% (range, 42%-53%) for Child 3 over an 8-month period, and 6% (range, 45%-65%) for Child 4 over an 8-month period. For all hildren, the highest perentage of orret responding was made during sessions in whih stereotypy was used as a reinforer. In addition, the hildren's performane during sessions of the varied onsequenes was at least slightly higher than in the food ondition. Inspetion ofthe individual data suggests that only stereotypy served as a onsistent reinforer for Child 1. The food ondition was assoiated with a derease in orret responding ompared with baseline, perhaps beause food beame less salient for Child 1 or beause the inaessibility of stereotypy in the food ondition was punishing. This possibility may also explain the dereasing trend for the varied ondition. Child 2 also dereased his orret performane ompared with baseline in both onditions in whih food was available. For Children 3 and 4, both the stereotypy and varied onditions were reinforing. Results of experimental session and postsession observations for Children 1, 2, and 3 are shown in Figure 2. Perentages of intervals of ourrene of stereotypy and off-task behavior were ombined beause the off-task behavior seldom ourred, and were averaged aross sessions of eah ondition. For all 3 hildren, overall ourrene of stereotypy and off-task behaviors did not inrease during sessions in whih stereotypy was used as a reinforer. Indeed, for Children 1 and 2, these inappropriate behaviors ourred less frequently during stereotypy or varied onsequene onditions than during food onditions. Similarly, no large inreases in stereotypy and off-task behaviors ourred during postsession observations following sessions of the stereotypy ondition. For Child 1 and Child 2, these disruptive behaviors dereased following sessions of this ondition ompared to the food ondition. Child 4's side-effet data are also presented in Figure 2. The three panels display the results of the experimental session observations and the postsession observations for stereotypy, off-task behavior, and aggression, respetively. As in the other hildren, no inreases in stereotypy or off-task behavior were assoiated with the use of stereotypy as a reinforer. Of speifi interest is the differene between the mean perentage ourrene of off-task behavior and aggression, whih were reorded separately. Both aggressive and off-task behaviors ourred more frequently during postsession observations than during the experimental onditions. It is possible that unobserved fators may have led to an inrease in aggression and off-task behaviors. However, it is also likely that using stereotypy as a reinforer may have been effetive in dereasing this hild's aggression in addition to inreasing task performane. The tasks presented during all the experimental onditions may have beome onditioned reinforers, thus dereasing the ourrene of aggression during the food ondition as well. Results of home observations of Child 4's stereotypy are shown in Figure 3. The mean frequeny of ourrene ofstereotypy during the 5-min hourly observation periods was averaged aross eah week. The mean frequeny of stereotypy at home dereased after experimental onditions began, suggesting that negative side effets did not our at home. Child 4's mother reported that she did not implement any proedures that ould aount for this derease. However, the home data must be interpreted with aution beause the dereasing trend ourred before treatment was implemented. These results extend previous literature on reinforer effetiveness by suggesting that ( the use of stereotypy as a reinforer may be more effetive in improving hildren's task performane than the use of edible reinforers, (b) varied reinforer onditions were not superior to single reinforer onditions when the reinforer was stereotypy, and ()

8 17 MARJORIE H. CHARLOP et al. E L- L- C', 9 Child I 8 ^ / ~~~~Stereotypy 8 ~ ~ t \e Varied 1 4-,) u. U) L- L- U 4-)- U) 1 Child 4 9 t - StereotypyN,, L- U) a~ 8 7 6( / Food -Varied 5( lo Conseutive Experimental Figure 1. Performane during stereotypy, food, and varied onsequene onditions for Children 1, 2, 3, and 4. the use of stereotypy as a reinforer was generally not assoiated with speifi negative side effets and may have atually dereased some inappropriate behaviors, as illustrated by Child 4's data. EXPERIMENT 2 Given the generally positive findings obtained when stereotypy was used as a reinforer, we deided to study the reinforing effets of delayed eholalia. Previous literature suggests that some forms of delayed eholalia may have reinforing properties (e.g., Lovaas et al., 1977; Prizant & Rydell, 1984); thus, it seemed reasonable to explore the use of this behavior as a reinforer. METHOD Subjets Three verbal autisti boys partiipated in this experiment. Child 1 (hronologial age, 8.5 years;

9 C'h C',. in ) 4- V m - +- C C.) 4_- II- U1) al) 4-, 4-' L.) i 4C C', During Experimental 4 r E Child 3 IH During Experimental I S n ABERRANT BEHAVIORS Experimental Free-Play Post- Post- Experimental Experimental Work Free-Play Post- Post- Experimental Experimental Work Free-Play Mean perentage ourrene of stereotypy and off-task behavior during experimental onditions and postexperi- Figure 2. mental sessions for Children 1, 2, 3, and 4. a1) L. 4- Uf) D 4-, 4-,) CL 16_J IChild 4: Stereotypyl 1 In During Experimental Post-Experimental Child 4: Off-task Behavior I rl During Experimental Post-Experimental Consequene Conditions Child 4: Aggressionj *Food. *3 Varied During Experimental ti Post-Experimental Stereotypy 171

10 172 MARJORIE H. CHARLOP et al. IQ, 1) frequently displayed delayed eholalia and typially repeated phrases heard on game shows, suh as "I'll go with the X to blok." or "Ding! Ding! Ding! You win again!" This hild also engaged in frequent stereotypi behaviors (e.g., rossing eyes, lining up toys, finger flapping, and finger rubbing). Child 2 was an 8.-year-old boy (IQ, 67) who engaged in a variety of disruptive behaviors during work sessions, induding aggression, tantrums, yelling, and nonompliane. He had a relatively large voabulary and often spoke spontaneously. Delayed ehoes frequently uttered by this hild inluded "Red, red, red," "It doesn't stop at the eight, it stops at the nine!," "Go to bed!," and "Eat your beef stew!" Child 2's most frequent forms of stereotypy were paing, tapping, roking bak and forth, and head rolling. Child 3 (hronologial age, 9.3 years; IQ, 69) engaged in some appropriate spontaneous speeh (e.g., requests for speifi foods or toys); however, most of his utteranes onsisted of immediate and delayed eholalia, suh as "Get out of there right now!," "Don't poke the dog!," or "Don't be silly, ontrol yourself!" He also engaged in stereotypi behaviors (e.g., hand flapping, rubbing fingers on different textures, spinning objets) as well as offtask behaviors (e.g., nonompliane, inappropriate bursts of laughter). Tasks Child l's tasks onsisted of mathing a diffiult geometri design, adding up oins to a requested amount, and answering ause and effet questions (e.g., "What happens when you drop a ball?"). Tasks for Child 2 were a before/after disrimination task, naming days of the week, and naming items in a speifi ategory (e.g., "Name five fruits."). The tasks for Child 3 were expressive pronouns (e.g., "Who has a wath on?" "You do"), and possessive pronouns (e.g., "Whose nose is this?" "My nose"). Proedure A multielement design was used to ompare the three potential reinforer onditions: delayed ehoes ) C L. ~ r lchild 4: At Home (Treatment Started) </ Stereotypy I 5 1 Conseutive Weeks Figure Child Mean ourrene of stereotypy at home for as a onsequene, food as a onsequene, and varied (delayed ehoes or food) onsequenes. Experimental sessions were onduted as desribed earlier, exept for Child 3, whose experimental sessions lasted 1 min beause he was presented with only two tasks. Dependent measures onsisted of the hildren's task performane; ourrene of stereotypy and off-task behaviors (both during and after experimental sessions) were also reorded. However, during these observations, the ourrene of delayed eholalia (when not used as a reinforer) was sored separately from the ourrene of stereotypy and off-task behaviors. During experimental onditions in whih delayed eholalia was used as a onsequene, the hild was permitted to utter a preferred delayed eho after eah orret response. The experimenter ued the hild after a orret answer by saying, "That's right! What do you want to say?" Initially, beause eholalia had previously been disouraged, the experimenter said, "What do you want to say? Do you want to say 'Red, red, red'?" A list of highfrequeny delayed ehoes to be used as reinforers was ompiled prior to the study by observation and by parental report. Reinforers in this ondition were "Ding! Ding! Ding! You win again," and "Math Game '83" for Child 1; "Eat your beef stew," "Red, red, red," and "It doesn't stop at the eight, it stops at the nine" for Child 2; and "No laughing," "Don't be silly," "Como esta, Senor?" "Let's eat grilled heese sandwihes," and "Get out of there right now, do you hear me?" for Child 3. 15

11 ABERRANT BEHAVIORS 173 Additional Analyses for Child 3 Additional data were olleted for 1 hild to permit a more thorough analysis of possible side effets. Child 3's postsession observation period was extended from 15 to 3 min with work and freeplay sessions ombined, and Child 3's mother, who had previously been trained in data olletion, reorded daily frequeny of ourrene of delayed eholalia at home, prior to and throughout the study. Child 3 was hosen for the additional analyses beause he was the last hild to partiipate in this experiment. Reliability Interobserver reliability was olleted and alulated as desribed earlier. Average reliability for task performane was 99%, 1%, and 99% for Children 1, 2, and 3, respetively. Average reliabilities for ourrene and nonourrene of stereotypy, off-task behavior, and delayed eholalia are presented in Table 4. As in Experiment 1, six reliability heks were taken at the after-shool program between Child 3's parent and the experimenter. Cheks onsisted of simultaneously observing Child 3 during a 1-min free play and reording frequeny of ourrene of delayed eholalia. REsurrs AND DISCUSSION Figure 4 shows the hildren's task performane aross the three reinforer onditions. The horizontal line denotes the average for baseline performane, whih was 6% (range, 5%6-62%) for Child 1 during a 7-month period; 55% (range, 5%-58%) for Child 2 over an 8-month period; and for Child 3, 55% (range, 48%-58%) over an 8-month period. For Children 1 and 3, the delayed eholalia reinforer onditions were assoiated with the highest task performane, although there was little differene between the delayed eholalia and varied reinforer onditions aross hildren. For Child 2, the varied ondition was slightly superior to the delayed eholalia ondition. Varied reinforers were more effetive in improving performane in this experiment, perhaps beause of the larger ratio of E so 4H- L- a- o ~ 9oFI Child 1 8 I 7 F A. Delayed % s /Eholalla *"Varled Average Baseline / Pertormane Food Conseutive Experimental Figure 4. Performane during delayed eholalia, food, and varied onsequene onditions for Children 1, 2, and 3. ehoes to food (the hildren in this experiment atually requested to eho, and at times pushed away the food in preferene for an eho). The food ondition was reinforing for Children 2 and 3, but not as effetive as the other onditions. For Child 1, performane deteriorated under food onsequenes ompared with baseline.

12 174 MARJORIE H. CHARLOP et al Child 3: Stereotypy U) ) U) L. L- Cl) D L- U1) 4-) C 4-, C UL) L. CL U) During Experimental Post- Experimental Work Post- Experimental Free-Play Q ~14 > 6 4-J C: 4 4-., 2 ) ~ H~ During Experimental Post-Experimental Child 3: Off-task Behavior IlEIII During Experimental Post-Experimental Child 3: Delayed Eholalia 15 1 S C Post-Expermen 1 Free-lay Sssio 8 Consequene Conditions Food M Varied Delayed -X Eholalia During Experimental Post- Experimental Work During Experimental Post-Experimental Figure 5. Mean perentage ourrene of stereotypy, off-task behavior, and delayed eholalia during experimental onditions and postexperimental sessions for Children 1, 2, and 3.

13 ABERRANT BEHAVIORS 175 Results of experimental session and postsession observations of the ourrene of stereotypy, offtask behavior, and delayed eholalia are provided in Figure 5 for Children 1 and 2. Ourrene of suh behaviors during experimental sessions and during postsession observations did not differ muh aross the three reinforer onditions, suggesting no negative side effets. Inreases were seen, however, in the postexperimental free-play sessions during all onditions for Children 1 and 2. Perhaps, for these hildren, the lak of struture and supervision in the free-play setting set the oasion for the ourrene of inappropriate behaviors. Suh inreases did not appear to be a funtion of any partiular experimental ondition. Child 3's side-effet data are also presented in Figure 5. As in Children 1 and 2, results of Child 3's session and postsession observations indiated that little differene in inappropriate behaviors ourred. Home observations of Child 3's ourrene of delayed eholalia are presented in Figure 6; daily frequeny of ourrene was averaged aross eah week. As an be seen, there was a dereasing trend in delayed eholalia at home, and no inreases were assoiated with using an aberrant behavior as a reinforer. Child 3's mother reported no hange in her management of her son's delayed eholalia. However, the home data must be interpreted with aution, beause the dereasing trend was observed before treatment began. The overall results of Experiment 2 suggest that autisti hildren's delayed ehoes may serve as reinforing events and may be more salient than traditionally used edibles. EXPERIMENT 3 The results of Experiments 1 and 2 demonstrated the effiay of using stereotypy and delayed eholalia as reinforers. In this experiment, a third aberrant behavior, perseverations with speifi objets, was studied as a potential reinforer. Speifially, sessions of perseverative behavior were ompared with food and with stereotypy. In addition, sideeffet measures were olleted for all hildren, both during and after experimental onditions and at home. a, C 25 3 r Child 3- At Homel u 2 I Conseutive Weeks Figure 6. for Child 3. Mean ourrene of delayed eholalia at home METHOD Subjets Three autisti boys partiipated in Experiment 3. Child 1, a 9.7-year-old boy (mental age, 3.7 years), displayed high frequenies of immediate and delayed eholalia but minimal appropriate speeh. During work sessions, Child 1 frequendy engaged in off-task behaviors (e.g., rying, laughing, nonompliane) and stereotypy (e.g., tapping objets, body posturing). He also displayed perseverative behavior with five speifi plasti toy animals, a See-N-Say toy, and a Humpty Dumpty doll. In addition to seeking out these speifi objets, Child 1 ontinually talked about these toys as well as about a few speifi food items (e.g., "I love those panakes with syrup."). Child 2 (hronologial age 6.9 years; mental age, 4.5 years) was a verbal boy who spontaneously spoke in fill sentenes and displayed little eholalia. However, he was frequently nonompliant and oppositional when presented with a diffiult task. He also displayed poor eye ontat and stereotypy, partiularly rubbing the edges of a blanket at home. Child 2 perseverated on trees and leaves, partiularly books about pine trees and atus. His mother reported that, if permitted, he would play outside with branhes and leaves for hours at a time. Additionally, he would onstantly ask his parents the same questions about different kinds of trees. Child 3 (hronologial age, 6.2 years; mental age, 3.1 years) rarely displayed spontaneous speeh,

14 176 MARJORIE H. CHARLOP et al. but did oasionally use short sentenes. He also exhibited immediate and delayed eholalia, as well as frequent stereotypy (e.g., twisting hair, repetitively blinking eyes, twirling broken twigs in front ofeyes). He also had several perseverative behaviors with objets, induding lawn mowers, hain saws, and Honda ars (speifially, 1977 Honda Civis). His mother reported that he would dimb trees to wath neighbors tending their lawns, and on several oasions he ran away from home to seek out lawn mowers, hain saws, and Hondas in garages. Child 3 also perseverated on home improvement stores (e.g., Builder's Emporium) and disount stores (e.g., K-Mart, Best Produts). Tasks As in the previous experiments, three tasks were seleted for eah hild for presentation during experimental sessions. Tasks hosen were prepositions, same/different disriminations, and expressive pronouns for Child 1; telling time by the quarter hour, reall of four previous ations, and reall of days of the week or months of the year for Child 2; and pronouns, reall of three previous ations, and what's missing reall task for Child 3. Proedure During baseline, eah hild was presented with typial 15-min work sessions, during whih the three seleted tasks were presented as in the food ondition. Following baseline, the reinforer onditions were ompared. Perseverative behavior (when not used as a reinforer) was sored if the hild talked about, reahed out for, or verbally requested his speifi preferred objet. Unlike the previous two experiments, a stereotypy ondition replaed the varied onsequene ondition as the third reinforer ondition and was ompared against both edibles and perseverative behavior. Food and stereotypy as onsequenes. of food and stereotypy onsequene onditions were presented as desribed previously. Potential reinforers in the stereotypy ondition were, for Child 1, bouning a small rubber ball on the table for 3 to 5 s; for Child 2, waving fingers in front of eyes or rubbing the edges of a partiular orner of his blanket; and for Child 3, twisting strands of hair in a partiular area of his head or twirling a twig (bent in a ertain way) in front of his eyes. Perseverative behavior as a onsequene. of this ondition onsisted of providing brief aess to an objet the hild perseverated on ontingent upon eah orret response. After eah orret answer, the hild was presented with one of these objets for 3 to 5 s. Potential reinforers available in this ondition were, for Child 1, a See-N- Say toy, five plasti animals (pig, ow, horse, frog, and duk), and a Humpty Dumpty doll; for Child 2, one partiular book about trees, one partiular book about atus, and the opportunity to talk about atus and trees; and for Child 3, a Honda Civi ar advertising booklet and a Best Produts atalog. Home observations. Prior to and throughout presentation of experimental onditions, parents (previously trained in data olletion) reorded data on the ourrene of stereotypy and perseverative behaviors at home. For Children 2 and 3, frequeny data were olleted ontinuously when the hild was at home with the parent. Child l's mother requested that she not be required to ollet data on stereotypy beause the behavior ourred with great frequeny. However, frequeny of Child 1's perseverative behavior was reorded by the mother during predetermined 1-min observation periods, three times a day. Reliability Reliability for the hildren's task performane was 93% for Child 1, 98% for Child 2, and 94% for Child 3. Average interobserver agreements for ourrene and nonourrene of stereotypy, offtask behavior, and perseverative behavior are presented in Table 4. Three reliability heks were taken throughout the study with eah parent; eah hek onsisted of the parent and experimenter observing the hild simultaneously during a 1- min free-play session and reording ourrenes and nonourrenes of stereotypy (for Children 2 and 3) and perseverative behavior. RESULTS AND DISCUSSION The 3 hildren's task performanes are presented in Figure 7. For all hildren, the highest perentage

15 ABERRANT BEHAVIORS 177 E L- _ -4--) 4t I Consequene Conditions [Child 11 Behavior A // \ / Perseverative / / - -*-Stereotypy A v Food 8, AanStereotypy ~Food Conseutive Experimental Figure 7. Performane during perseverative behavior, stereotypy, and food onsequene onditions for Children 1, 2, and 3. of orret responding was made during sessions in whih perseverative behavior served as reinforers. The stereotypy ondition was only slightly less effetive for Children 1 and 3. The food reinforers were assoiated with the lowest task performane, being at or below baseline levels for all hildren. Mean ourrenes of stereotypy, off-task behavior, and perseverative behavior during and after experimental sessions are shown in Figure 8. Reall that postexperimental sessions onsisted of both work and free-play settings ombined. For eah hild, ourrene of eah dass of behaviors is averaged aross the total number of sessions for eah ondition. As an be seen, stereotypy, off-task, and perseverative behaviors did not inrease when perseverative or stereotypi behaviors were used as reinforers, exept for Child 2. These findings are similar to those of Experiments 1 and 2 in suggesting that no negative side effets ourred. Results ofhome observations are shown in Figure 9. Note that for Children 2 and 3, baseline reording of perseverative behavior was begun several weeks prior to baseline reording of stereotypy, resulting in fewer baseline data points for stereotypy. For Children 1 and 2, perseverative behavior initially inreased when experimental onditions were introdued. However, a dereasing trend ourred after the initial inrease. This was also evident with stereotypy for Child 2. For Child 3, frequeny of perseverative behavior remained low after implementation of the experimental onditions; however, this result is diffiult to interpret beause of the dereasing trend during baseline. Similar results ourred for Child 3's stereotypi behavior. The parents of all 3 hildren reported that they made no hanges in their management of the aberrant behaviors during the ourse of the study. These findings suggest that both stereotypi and perseverative behaviors were more effetive than edibles in improving the hildren's task performane, with perseverative behavior slighdy more effetive than stereotypy. Negative side effets were not observed at the after-shool program or at home. GENERAL DISCUSSION In three experiments, autisti hildren's aberrant behaviors were suessfully used as reinforers to improve their performane on diffiult tasks, and overall inreases in aberrant behavior did not our as an undesirable side effet. Comparable results from home observations of inappropriate behaviors provided additional support for the effiay of using aberrant behaviors as reinforers. Differenes in the hildren's task performane aross the experimental

16 178 MARJORIE H. CHARLOP et al. - o 8 46 > IlChild ii 7 a 6 t 5 4- > 3-2 IOILLWL {) During During Experimental Post- Post-Experimental L Baseline Baseline 16d poteprienass i Child 21 o > 12.o - C)1 5.in 2 (3 8 )U C L 6 4-) ) e- During During Experimental Post- --Post-Experimental Baseline Basel ine L) Consequene L > Conditions 8 4. Q. I~~~~~Child31 Food 6 --Perseverativ 5 >I Behavior 4 3 2> - During During Experimental Post- Post-Experimental Baseline Baseline Figure 8. Mean perentage ourrene of stereotypy, off-task, and perseverative behavior during experimental onditions and postexperimental. sessions for Children 1, 2, and 3.

17 ABERRANT BEHAVIORS yo 25 4&D L. 2 (1> ' LM (n. 2 O 4-O 15 C ',3 T I o L- v~o, ' ' 5 o} Ḷ = r I- I- I- d >1 a a- ) C:. E z C (U IChild 2 (Treatm ent 15 F, Perseverative Behavior 125 I Started) ) 1 I 75 F 5 F 25 F 2 C o 15 Li-, 1 (U am 4) U1) v # E F z 12 Child 3 1 I Conseutive Weeks Perseverative / Behavior 3, 25 u '' 2, 15, >1 (U5 r IChild 3 (Treatment Z Stereotypy Started) 5 Conseutive Weeks Figure 9. Mean ourrene of stereotypy and perseverative behavior at home for Children 1, 2, and 3. I 1

18 18 MARJORIE H. CHARLOP et al. onditions may be best explained in terms of the salieny of the aberrant behaviors used as reinforers (Rinover, Newsom, Lovaas, & Koegel, 1977; Wolery et al., 1985). It has been demonstrated that stereotypy an be reinforing, perhaps beause it ontains speifi sensory or pereptual properties (Rinover & Newsom, 1985), and it has been hypothesized that the pereptual reinforers provided by stereotypy are primary reinforers beause they serve an organi funtion of stimulation in the entral nervous system (Lovaas et al., 1987). Thus, it is not surprising that stereotypy was a potent reinforer for autisti hildren. Importandy, the superior task performane displayed by all hildren during delayed eholalia and perseverative behavior onditions suggests that these behaviors also provide highly salient reinforing properties for these hildren. Previous studies on sensory reinforement and sensory extintion (e.g., Rinover, 1978; Rinover, Cook, Peoples, & Pakard, 1979) have identified the reinforing auditory, visual, or proprioeptive sensory onsequenes that maintain stereotypi behavior in autisti hildren. It is possible that suh sensory onsequenes may also maintain eholali and perseverative behavior. Lovaas and his olleagues (Epstein et al., 1985; Lovaas et al., 1987) proposed that some forms of delayed eholalia and perseverative behavior may be more omplex (i.e., higher level) forms of stereotypi behavior, due to the repetitive nature of these behaviors, the omplex pereptual stimuli produed by them, and their interferene with aquisition of appropriate behaviors. Empirial support for this supposition has been provided by the results of long-term intensive treatment of autisti hildren, whih show that as the hildren learn speeh and aademi tasks, low-level stereotypy (e.g., body roking) is dereased and progression to intermediate levels of stereotypy (e.g., eholali speeh) and ultimately higher levels (e.g., perseveration on numbers) may our (Epstein et al., 1985). It is possible that perseverative behavior and delayed ehoes are more sophistiated forms of stereotypy and thus may be more salient reinforers for some hildren than stereotypy. The absene of observed negative side effets during and after work sessions for all experiments, as well as at home, provides important additional support for the use of aberrant behaviors as reinforers. The hildren engaged in the aberrant behaviors as reinforers in a ontrolled manner. They did not engage in exessive stereotypi responses or resist when a preferred objet was taken away after the 5 s of aess. The hildren often returned the objet unasked and waited patiently for the next trial. For example, after a orret response in Experiment 3, Child 1 held and gazed at the plasti toy ow, said, "I love that ow!" and immediately returned it to the therapist. Similarly, Child 4 (Experiment 1) seleted a sented magi marker from the table after a orret answer, handed it to the experimenter to be opened so he ould sniff it, and then took it bak and plaed it on the table without a request from the experimenter. These anedotal observations of the hildren's eagerness to work and their displays of ontrol when allowed to engage in the aberrant behaviors are quite enouraging. The diffiulty in eliminating autisti hildren's aberrant behaviors has been well demonstrated (e.g., Favell, MGimsey, & Jones, 1978; Foxx & Azrin, 1973; Marhant, Howlin, Yule, & Rutter, 1974; Rinover & Koegel, 1977; Shreibman & Carr, 1978). Rather than persisting in these efforts, a more pragmati approah may be to identify funtional aspets (i.e., reinforing properties) of these behaviors and use them to advantage (i.e., as reinforers) to teah new, adaptive responses. The identifiation and suess of suh salient and easy-touse reinforers provide teahers and therapists with an important and muh-needed alternative approah to standard eduational and behavior hange programs. Not all autisti hildren are ideal andidates for these proedures. For example, some hildren may not display perseverative behavior, or the objets may not be available (e.g., a traffi light). Some highly preferred forms of stereotypy, suh as saliva swishing or eye gazing, may not be easily ontrolled by the therapist. Finally, the present study did not address the long-term use of these reinforers, although our anedotal observations are onsistent with the experimental findings. In spite of these

19 ABERRANT BEHAVIORS 181 potential limitations, the proedures appear to be quite effetive and pragmati. Given the pervasive lak of motivation reported for many autisti hildren, the results of this study provide hope for shaping a more promising future for these speial hildren. REFERENCES Amerian Psyhiatri Assoiation. (198). Diagnosti and statistial manual ofmental disorders (3rd ed.). Washington, DC: Author. Egel, A. L. (1981). Reinforer variation: Impliations for motivating developmentally disabled hildren. Journal of Applied Behavior Analysis, 14, Epstein, L., Taubman, M. T., & Lovaas,. I. (1985). Changes in self-stimulatory behavior with treatment. Journal of Abnormal Child Psyhology, 13, Favell,J. E., MGimsey,J. F., &Jones, M. L. (1978). The use of physial restraint in the treatment of self-injury and as positive reinforement. Journal of Applied Behavior Analysis, 11, Fay, W. H., & Shuler, A. L. (198). Emerging language in autisti hildren. Baltimore: University Park Press. Foxx, R. M., & Azrin, N. H. (1973). The elimination of autisti self-stimulatory behavior by overorretion.journal of Applied Behavior Analysis, 6, Hung, D. W. (1978). Using self-stimulation as reinforement for autisti hildren.journal ofautism and Childhood Shizophrenia, 8, Lovaas,. I., Koegel, R. L., Simmons, J. Q., & Long, J. S. ( 1972). Some generalization and follow-up measures on autisti hildren in behavior therapy. Journal ofapplied Behavior Analysis, 6, Lovaas,. I., Newsom, C., & Hikman, C. (1987). Selfstimulatory behavior and pereptual reinforement.journal of Applied Behavior Analysis, 2, Lovaas,. I., Varni, J., Koegel, R. L., & Lorsh, N. L. (1977). Some observations on the non-extinguishability of hildren's speeh. Child Development, 48, Marhant, R., Howlin, P., Yule, W., & Rutter, M. (1974). Graded hange in the treatment of the behavior ofautisti hildren. Journal of Child Psyhology and Psyhiatry, 15, Premak,ID. (1959). Towardempirialbehaviorlaws:Positive reinforement. Psyhologial Review, 66, Prizant, B. M., & Rydell, P. J. (1984). Analysis of the funtions ofdelayed eholalia in autisti hildren.journal of Speeh and Hearing Researh, 27, Riks, D. M., & Wing, L. (1975). Language, ommuniation, and the use of symbols in normal and autisti hildren. Journal of Autism and Childhood Shizophrenia, 5, Rinover, A. (1978). Variables affeting stimulus-fading and disriminative responding in psyhoti hildren. Journal of Abnormal Psyhology, 87, Rinover, A., Cook, R., Peoples, A., & Pakard, D. (1979). Sensory extintion and sensory reinforement priniples for programming multiple behavior hange. Journal of Applied Behavior Analysis, 12, Rinover, A., & Koegel, R. L. (1977). Researh on the eduation ofautisti hildren: Reent advanes and future diretions. In B. B. Lahey & A. E. Kazdin (Eds.), Advanes in linial hild psyhology (Vol. 1, pp ). New York: Plenum Press. Rinover, A., & Newsom, C. D. (1985). The relative motivational properties of sensory and edible reinforers in teahing autisti hildren. Journal of Applied Behavior Analysis, 18, Rinover, A., Newsom, C. D., Lovaas,. I., & Koegel, R. L. (1977). Some motivational properties of sensory stimulation in psyhoti hildren. Journal of Experimental Child Psyhology, 24, Shreibman, L., & Carr, E. G. (1978). Elimination of eholali responding to questions through the training of a generalized verbal response. Journal of Applied Behavior Analysis, 11, Sugai, G., & White, W. J. (1986). Effets of using objet self-stimulation as a reinforer on the prevoational work rates of an autisti hild. Journal of Autism and Developmental Disorders, 16, Wolery, M., Kirk, K., & Gast, D. L. (1985). Stereotypi behavior as a reinforer: Effets and side effets. Journal ofautism and Developmental Disorders, 15, Reeived May 6, 1989 Initial editorial deision July 3, 1989 Revisions reeived September 28, 1989; November 16, 1989 Final aeptane Deember 4, 1989 Ation Editor, David P. Waker