Human Extinction Responding Following VI and VI-CRF Schedules of Reinforcement

Transcription

1 Western Michigan University ScholarWorks at WMU Master's Theses Graduate College Human Extinction Responding Following VI and VI-CRF Schedules of Reinforcement Vaughn Thomas Mawhinney Western Michigan University Follow this and additional works at: Part of the Experimental Analysis of Behavior Commons Recommended Citation Mawhinney, Vaughn Thomas, "Human Extinction Responding Following VI and VI-CRF Schedules of Reinforcement" (1968). Master's Theses This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact

2 HUMAN EXTINCTION RESPONDING FOLLOWING VI AND VI-CRF SCHEDULES OF REINFORCEMENT by V.' Thomas Mawhinney A Thes i s Submitted to the Faculty of the School of Graduate Studies in p a rtia l f u lfillm e n t of the Degree of Master of Arts Western Michigan U niversity Kalamazoo, Michigan August 1968

3 ACKNOWLEDGEMENTS I would lik e to extend a note of g ra titu d e to Drs. B.L. Hopkins and E. Wade H itz in g. Thanks to th e ir cooperation in rendering f a c i l i t i e s, apparatus, and su b je cts, th is research p ro je c t was made p ossible. I have indeed benefited from t h e ir suggestions and cons tru c tiv e c ritic is m s as well as from those of Drs. Jack Michael and Roger E. U Ir ic h. In a d d itio n, tr ib u te must be paid to my dear w ife, S a lly. W ithout S a lly 's stamina and e n th u s ia s tic moral support, i t is doubtful th a t I would be completing one of the last requirements fo r the Master of Arts degree. V. Thomas Mawhinney

4 M A STER 'S THESIS M M A W H IN N EY, Vaughn Thomas HUM AN E X TIN C TIO N RESPONDING FOLLOWING V I AND V I-C R F SCHEDULES OF R EIN FO R C EM EN T. W estern Michigan U n iversity, M.A., 1968 Psychology, experim ental U niversity M icrofilm s, In c., A n n A rbor, M ichigan

5 TABLE OF CONTENTS PAGE ACKNOWLEDGEMENTS i i INDEX OF FIGURES... INDEX OF T A B L E S... i v vi I NTRODUCT I O N... 1 METHOD... 3 S u b j e c t s... 3 Experimental Room... 3 Response and Reinforcement Console... 4 Reinforcement Procedure... 4 Experimental Procedure RESU LTS Phase 1 and 2 V I 7 V I 7 and VI 15 V Phase 3 Ext i net ion-exti n cti o n Phase 4 D R 0 -D R Phase 5 V I V I Phase 6 C R F - V I Phase 7 E x tin c tio n E x t i n c t i o n...24 DISCUSSION REFERENCES... 35

6 INDEX OF FIGURES Figure Page Schematic of the response and reinforcem ent 6 console. The component parts of the console are indexed A through D. The rates of responding emitted by Subject 15 A in both the le f t and rig h t response components during each 20 minute session. L e ft component response rates are indicated with c irc le s and a s o lid line while tria n g le s and a broken line are used to indicate the response to ta ls fo r the rig h t component. The hollow c ir c le and tria n g le shown in Session 62 indicate responses per minute under the respective reinforcem ent contingencies fo r the f i r s t two 5 minute components. Responses during the last two 5 minute components of th a t session were on e x tin c tio n. Experimental manipulations fo r both components are indicated across the top of the graph. The rates of responding emitted by Subject 17 B in both the le f t and rig h t response components during each 20 minute session. Left component response rates are indicated with c irc le s and a s o lid line while tria n g le s and a broken line are used to indicate the response to ta ls fo r the rig h t component. The hollow c ir c le and tria n g le shown in Session 39 indicate responses per minute under the respective reinforcem ent contingencies fo r the f i r s t two 5 minute components. Responses during two 5 minute components of th a t session were on e x tin c tio n. Experimental m anipulations fo r both components are indicated across the top of the graph. Rates of responding by Subject C in both the 19 l e f t and rig h t response components during a 20 minute session. L e ft component response rates are indicated with c irc le s and a s o lid line w hile tria n g le s and a broken line are i v

7 Fi qure Page used to indicate the response rates fo r the rig h t components. Experimental manipulations fo r both response components are indicated across the top of the graph. 5 Systematic sequential reduction in response 22 rates between 5 minute components fo r Subjects B and C in Phase 3 e x tin c tio n. 6 Responses per minute emitted by Subject A during 27 each of the 5 minute components occurring during Phase 7 e x tin c tio n. 7 Responses per minute emitted by Subject B during 29 each o f the 5 minute components occurring during Phase 7 e x tin c tio n. 8 Responses per minute emitted by Subject C during 31 each of the 5 minute components occurring during Phase 7 e x tin c tio n.

8 INDEX OF TABLES Table 1 2 Reinforcers th a t Subject A could purchase with points he had earned during an e x p e rimental session. Rei.nforcers th a t Subjects B and C could purchase with points they had earned during an experimental session. Schedules and number of sessions in each experimental phase fo r Subjects A, B and C. Pape

9 High ra+e, stereotyped responding on the part of incarcerated patients is a common phenomenon in mental in s titu tio n s. These types of behavior problems may include many d iffe re n t topographies, but the common denominator is always a high rate of responding. Some examples of these phenomena are rocking back and fo r th, touching various objects in the environment, pacing, turning or tw ir lin g about, or perhaps rubbing the fingers together in various fashions. One e ffe c tiv e technique to reduce the frequency of responding is punishment (Azrin and Holz, 1966). However, the use of e ffe c tiv e punishers to change the behavior of patients is severely re s tric te d in most, i f not a l l, state mental in s titu tio n s. The other frequently employed technique fo r e Iim in a tin g behavior is e x tin c tio n (Ayllon and Michael, 1959; W illiam s, 1966). E xtinction procedures, however, require the id e n tific a tio n and removal of the m aintaining re in fo rce rs. This presents a problem in th a t the re inforcers m aintaining stereotyped responding are ty p ic a lly not e a s ily id e n tifie d. One other method th a t could be employed in reducing the rate of a p a rtic u la r behavior is to d if f e r e n t ia lly re in fo rce other behavior (DRO) (Ayllon and Michael, 1959). When employing DRO procedures, responses which are incompatible or com petitive with the undesirable behavior are reinforced. This process is an e ffe c tiv e and well established technique, but becomes d i f f i c u l t when i t is applied to behavior occurring at a very high rate because i t becomes re la tiv e ly time consuming. 1

10 Other researchers have strongly suggested th a t behaviors maintained under in te rm itte n t schedules of reinforcement y ie ld more responses in e x tin c tio n than do those maintained under a schedule of' continuous reinforcem ent (CRF) (K e lle r and Schoenfeld, 1950; Wertheim and Singer, 1964; Skinner, 1938). This study is devoted to an in v e s tig a tio n of a possible procedure to reduce the frequency of high rate behavior by u t iliz in g the above mentioned phenomenon. Such a methodology would involve a response ra te, with a h is to ry of n a tu ra lly occurring in te rm itte n t reinforcem ent, being placed on an experim entally contrived CRF. Hopefully, when the contrived schedule of continuous reinforcem ent is removed, i t w ill leave the behavior less re s is ta n t to e x tin c tio n so th a t i t would not be maintained by the r e la tiv e ly lean schedule of n a tu ra lly occurring in te rm itte n t reinforcem ent. Three other in ve stig a tio n s have sought to answer th is e xp e rimental question. Spradlin (1962) performed a study with human retardates w hile L ike ly (1958) and Toombs (1961) performed conceptu a lly s im ila r animal studies. The re su lts of these studies do not support the general supposition. However, a ll of these studies employed group designs which are r e la tiv e ly in s e n s itiv e to individual differences and frequently employed experimental manipulations which were introduced independently of the ongoing behavioral sta te. Therefore, the experimental question remains of in te re s t both th e o re tic a lly and th e ra p e u tic a lly. This study is an experimental analogue of the more general therapeu tic problem of high rate stereotyped responding which is

11 found occurring in natural uncontrived s itu a tio n s. A stereotyped response was created and provided with a h is to ry of in te rm itte n t reinforcem ent. A short h is to ry of continuous reinforcem ent was then introduced and followed by e x tin c tio n. METHOD Subjects Three male mental patients of rather vague c lin ic a l diagnoses were u tiliz e d as subjects fo r th is study. Subjects were chosen on the basis of several c r it e r ia : ( 1) each lacked b iza rre psychotic behaviors which would have competed with th e ir e m ittin g the response employed as a dependent measure; (2 ) each would fo llo w a simple set of in s tru c tio n s ; (3) each had verbalized th a t he would "work" fo r candy, cookies, gum, o r, in the case of an old e r su b je ct, c ig a re tte s. Subject A was 33 years of age and had been in and out of the mental hospital f o r 20 years. At the time o f th is experiment, Subje c t A had obtained job placement, but s t i l l resided at the state h o s p ita l. Subjects B and C were both 15 years old and had been ho sp ita lize d fo r 7 and 8 years resp e ctive ly. All subjects were experim entally naive to the e xtent th a t they had never been involved in research which required responding on simple mechanical manipulanda. ExperimentaI Room The experiment was conducted in a 11? x 10 fo o t room th a t contained one door and one window. During experim entation, the

12 window was covered and the door was closed but not locked. The room was supplied w ith masking noise from a Grayson and S tadler white noise generator. The provided noise level was s u f f ic ie n t to mask most of the sounds from a c tiv ity outside of the experimental room as well as a ll of the noises produced by the programming equipment in the adjacent control room. Response and Reinforcement Console The response console as shown in Fig. I was black, had a sloping fro n t panel, and was located on a small ta b le in a corner of the experimental room. Two 1 inch diameter green lig h ts located above two Presin Model F206 counters with 5 inch numerals provided the means fo r reinforcem ent. When a p o in t was d e live re d, i t appeared on one of the counters accompanied by an audible c lic k as well as a second flash from the green lig h t located d ir e c tly above i t. Six? inch diameter white lig h ts were located d ir e c tly above 6 momentary response switches. Only response switches and white lig h ts 1 and 6 were u tiliz e d in th is experiment; the others were at a ll times inoperative. Standard electromechanical equipment was u tiliz e d in programming the response and reinforcem ent Console. Counters and a cumulative recorder were u tiliz e d in m onitoring the response rates from the control room. Rei nforcement Procedures Reinforcement consisted of points th a t were delivered to and accumulated upon the counters located above the response keys. Each reinforcem ent also included an audible c lic k and the simultaneous

13 ' Fig. 1. A schematic of the response and reinforcem ent consol* The component parts of the console are indexed A through D. / h/ / u

14 6 Response Switches 1-i Reproduced with permission of the copyright owner. Further reproduction prohibited without permission

15 fla sh in g of one of the green lig h ts fo r 5 second. At the end of each session, the points recorded on both counters were to ta le d and the subject was allowed to spend them fo r a v a rie ty of items at fixed p o in t prices. The ava ila b le items and the p o in t prices are shown in Table 1 fo r Subject A and in Table 2 fo r Subjects B and C. Subjects were required to spend a ll of t h e ir points immediately fo llo w in g each sess i on. Subject A, the 33 year-old p a tie n t, indicated great in te re s t in "working" fo r c ig a re tte s. This being the case, he could purchase from only a b r ie f l i s t of items. C igarettes were c u t in h a lf in order to economically accommodate the great q u a n tity th a t he could obtain when his responding on one of the keys was re inforced on a CRF schedule. Therefore, in the term inology of th is experiment, a " c ig a re tte " refers to 5 of a kin g -size d, u n filte re d c ig a re tte. Both Subjects B and C were non-smokers and said th a t they were p rim a rily interested in obtainin g cookies, candy, gum, e tc. These subjects were encouraged to suggest a common l i s t of items which could be purchased with the points they earned. The number of items on th is l i s t was not fixed and during the experiment, the subjects could request the addition of a p a rtic u la r item to the l i s t. If i t was fe a s ib le, the item was added and a point price fo r i t was immediately established. However, the l i s t was established as shown in Table 2 before any c ru cia l experimental m anipulations of independent va riables occurred.

16 8 Table 1 P oint cost per item fo r Subject A. I terns Poi nt Cost C i garette 10 Candy Bar 5 A Hard Candy 2

17 9 Table 2 P oint cost per item fo r Subjects B and C. ITEMS POINT COST Ba11 Poi nt Pen 75 Sma11 Pad of Paper 60 Candy Bar 50 Package of Gum 50 Penci 1 25 S tick of L ico rice 20 Hard Candy 10 S tick of Gum 10 Cook i e 1.0 Cup of Coffee 10 Ten Minute Play Period With a Hamster 10 A Magazine 10 An M&M Candy 2 A Marshma1low 2

18 ExperimentaI Procedure The subject was seated in fro n t of the response console a t the beginning of the f i r s t session and the fo llo w in g in s tru c tio n s were read: Mr. X, you will receive points fo r pressing these two keys. At the end of th is session you will be able to spend these points on cig a re tte s and candy. Watch th is panel clo se ly fo r these small white lig h ts wii I come on and te l I you which key to push to earn p o in ts. This lig h t will change position once in a w h ile, so you will have to follow i t and push the key located d ire c tly under the small white lig h t. Pushing a key which is not under a burning lig h t will not earn you points. When you earn a point you wi I I not only see the p oint on the counter, but you will hear a c lic k and also the big green lig h t over the counter will fla s h. Points earned by pressing the le f t key will appear on the le f t counter, while points earned on the rig h t key will show on the rig h t counter. While reading these in s tru c tio n s, the experimenter would reach out and touch each of the objects named in the in s tru c tio n s. These in s tru c tio n s were repeated u n til the subject verbalized th a t he understood. In order to va lid a te th a t the subject understood the task, other counters recorded responses to the u n lit key. A response to the u n lit key was defined as an in c o rre ct response and a substant i a l number of them would prompt a re p e titio n of in s tru c tio n s. Each session was 20 minutes in duration and consisted of four, 5 minute components which were programmed on a m u ltip le schedule. These fiv e minute components were alternated between the two response keys. The SD lig h ts above these two keys were a u to m a tica lly turned on to designate which manipulandum would produce reinforcem ent at any given time in the session. A ten second time out occurred at

19 the term ination of each fiv e minute component. During th is 10 D second period, no S s were presented and the response were rendered inoperative. levers The number of sessions th a t each subject spent under the d iffe r e n t experimental phases was p rim a rily dependent upon the r e la tiv e s ta bility of his response rate. Subjects A and B had re s p e ctive ly, 2 and 4 sessions of a v a ri- a b le -in te rv a I 7 second schedule o f reinforcem ent CVI 7 V I 7) in both response components. Both VI tapes used in th is study were interpolated from tapes made with the F leshier and Hoffman progression fo r generating VI schedules (1962). As shown in Table 3, schedules of reinforcement were then leaned to VI 15 V1 15 (seconds) in Phase 2. Subject C was begun on VI 15 VI 15 in session one. During Phase 3, e x tin c tio n schedules were incorporated in to the over a ll experimental design fo r two reasons: ( 1 ) to demonstrate the e ffic a c y of the points as re in fo rc e rs ; arid (2 ) to determine if response rates on the le f t and rig h t keys were roughly equal during e x tin c tio n. E x tin c tio n was implemented by simply w ith h o ld in g points. Both Subjects B and C showed a decrease in responding, but Subject A's responding continued unabated. The fa c t th a t the Phase 3 e x tin c tio n procedure did not produce a decrement in rate fo r Subject A introduced the p o s s ib ilit y th a t the previous high rate of responding was not co n tro lle d by points as re in fo rc e rs. To determine the re in fo rc in g p roperties of the p oints, a DRO procedure was employed fo r Subject A s responding during Phase 4. Points were administered contingent upon the

20 12 Table 3 Schedules and number of sessions in each experimental phase fo r Subjects A, B and C. PHASE SCHEDULES NUMBER OF SESSIONS L e ft Key Right Key A Subjeefs B C 1 VI-7 VI VI-15 VI Exti neti on Exti neti on DRO DRO 6 5 VI-15 VI CRF VI-15 5± 3 7 Exti net ion Exti notion 4± 4* 2

21 13 passage of a predetermined amount of time since the last response. A Grayson and Stadler e le c tro n ic tim er was used to syste m a tica lly increase the DRO time requirement from 0.1 to 0.5 seconds. The VI 15 VI 15 schedules were reintroduced in Phase 5 fo r a ll subjects and were maintained u n til response rates had s ta b iliz e d. During Phase 6, responses in the le f t components were placed on CRF while the rig h t component responses were maintained on a VI-15 schedule of reinforcem ent. This manipulation was made in lig h t of the fa c t th a t a ll three subjects showed a co n siste n tly higher rate of responding in the le f t component. Subjects A and B were placed on Phase 7 e x tin c tio n during the middle of a session. The f i r s t two 5 minute components were under th e ir respective Phase 6 (VI 15 CRF) schedules of reinforcem ent while the last two response components were placed on Phase 7 e x tin c tio n. However, with Subject C, e x tin c tio n schedules were programmed on both keys e xa ctly as was done during Phase 3. RESULTS Phase 1 and 2 VI-7-VI-7 and VI-1 5-V 1-15 Only Subjects A and B received Phase 1 tra in in g. Data from these sessions are not presented in Figs. 2 and 3 because the VI 7 V I 7 schedules were u tiliz e d only as preparatory tra in in g to the VI 15 VI 15 baseline schedules. During Phase 2, the response rate of Subject A in Fig. 2 varied from a low of approximately 289 per minute to a high of 330 per minute, while the rates of Subjects B (Fig. 3) and C (Fig. 4) varied

22 Fig. 2. The rates of responding emitted by Subject A in both the le f t and rig h t response components during each 20 minute session. Left component response rates are indicated with c irc le s and a s o lid lin e while tria n g le s and a broken line are used to indicate the response to ta ls fo r the rig h t component. The hollow c ir c le and tria n g le shown in Session 62 indicate responses per minute under the respective reinforcement contingencies fo r the f i r s t two 5 minute components. The last two 5 minute components of th a t session were on e x tin c tio n. Experimental manipulations fo r both response components are indicated across the top of the graph.

23 \ 400 z 300 s <0 u w 200 o Q_ 03 LU o: LEFT H-EVER RIGHT LEVER V I- 15 EXT. DRO VI-15 CRF - LEFT EXT. VI- 15 EXT. DRO VI-15 VI-15 RT. EXT. I 6 V I «I V > «9 *» V 0 8 V B I V? f B I «0 9 v ST r « SESSIONS

24 16 Fig. 3. The rates of responding emitted by Subject B in both the le f t and rig h t response components during each 20 minute session. L e ft component response rates are indicated with c irc le s and a s o lid line while tria n g le s and a broken line are used to indicate the response to ta ls fo r the rig h t component. The hollow c ir c le and tria n g le shown in Session 39 indicate responses per minute under the respective reinforcement contingencies fo r the f i r s t two 5 minute components. The last two 5 minute components of th a t session were on e x tin c tio n. Experimental manipulations f o r both response components are indicated across the top of the graph.

25 17 X X UJ UJ LEFT LEVER RIGHT LEVER u. UJ _l a c L o >. GO ro ro ro co CM 10 to >> CM CM CM CM 00 SESSIONS h- f- X X U1 UJ CD CM > > 00 CD CM in

26 Fig. 4. Rates of responding by Subject C in both the le ft and rig h t response components during a 20 minute session. response rates are indicated with c irc le s and a s o lid Left component line while tria n g le s and a broken line are'used to indicate the response rates fo r the rig h t components. Experimental manipulations fo r both response components are indicated across the top of the graph.

27 19 t- X X UJUI LEFT LEVER RIGHT LEVER 111K IO o > in to >> CM X X 111 UJ GO SM0ISS3S > > T o o o o o o o PO CM *nim / sasnodsaa

28 from approximately 64 to 127 per minute and 70 to 210 per minute re sp e ctive ly. During VI 15 VI 15 tr a in in g, none of the subjects displayed c o n s is te n tly higher rates of responding in the le f t or rig h t components. There was very l i t t l e v a r ia b ilit y between rates on the le f t and rig h t response components w ith in sessions during th is experimental phase. Phase 3 E x tin e tio n -E x tin o tio n Subjects B and C in Figs. 3 and 4 showed a decrease in response rates during the two sessions of Phase 3 e x tin c tio n procedures. By the second session, Subject B's o ve ra ll response rate had fa lle n to 24 per minute w hile Subject C was responding at 34 per minute. This decrease c o n stitu te d a decrement of approximately 100 and 147 responses per minute re sp e ctive ly. Both Subjects B and C showed a system atic sequential reduction in response rates across the four 5 minute components occurring in each of the Phase 3 e x tin c tio n sessions. Fig. 5 indicates responses per minute in successive 5 minute components during e x tin c tio n fo r both subjects. Since Subje c t A did not show a large reduction in response rates in e ith e r component during e x tin c tio n, a graph depicting response rates during 5 minute components is not presented. However, there was a s lig h t decrease in rate from Session 29 to Session 34 in the le f t component as seen in Fig. 2. This appeared to be a system atic divergence of the component ra te s, but during Session 35, both component response rates again became approximately equal. Phase 4 DR0-DR0 A DRO schedule was u tiliz e d in order to reassess the re in fo rc in g

29 Fig. 5 Systematic sequential reduction in response rates between 5 minute components fo r Subjects B and C in Phase 3 e xti neti on.

30 22 LlJ CO 111 CO O LlI Ix l CO» o 0 ) h - CO o LlI LlI CO ~D» m z> CO 5 MINUTE COMPONENTS NIIN /s a S N O d S a d

31 23 properties of points fo r Subject A. The s u b je c t s high response ra te ' made i t necessary to use a DRO.1 second. Time values above.1 second were in e ffe c tiv e in th a t the subject never paused long enough to be re in fo rce d. During Sessions 41 and 42, the rate was "shaped" down by syste m a tica lly increasing the DRO time requirement to.5 seconds. The re s u lt was an overall redaction in rate of approximately 155 responses per minute. Phase 5 VI 15 VI 15 A ll three subjects resumed VI 15 V1 15 responding with higher rates in the le f t components. In Fig. 3, Subject A displayed much more, session to session as well as between components v a r ia b ilit y, than he showed in Phase 2, VI 15 V1 15 responding. During Session 16 (Fig. 4 ), Subject B was observed to be s it t in g on top of the console w hile pressing the levers with his fe e t. Though the topography was somewhat unusual, no anomalous changes occurred in response rates. Fie was therefore allowed to respond in th is fashion. In Session 26, the subject climbed o ff the top of the console, sat in the c h a ir and responded with h is hands. This change in topography was accompanied by a drop in rate of approximately 44 responses per minute. The subject was th e re fo re in stru cte d to never climb back on top of the console. Daily checks were made in order to be sure th a t the su bject had not climbed back on top of the console. During the fo llo w in g 8 sessions, Subject B showed more between components v a r ia b ilit y than had been evident in the previous 10 sessions. During the la st 4 sessions of VI 15 V1 15 reinforcem ent, the s u b je c t's response rates were s lig h tly higher in the le f t components.

32 24 Subject C, as seen in Fig. 4, was given fo u r sessions of Phase 5, VI 15 VI 15 tra in in g. During Sessions 11 and 12, the response rates fo r Subject C were e q u iva le n t with those of Phase 2, V1 15 VI-15 responding. Despite the drop in response rates in Sessions 13 and 14, the response rates fo r both components remained w ith in the lower lim its of session to session v a r ia b ilit y found in Phase 2. Phase 6 CRF-VI-15 During the f i r s t session th a t responses to the le f t switch were on CRF, an immediate increase in response rate occurred in the CRF components. Subjects B and C displayed increases in rates of 81 and 78 responses per minute, re s p e ctive ly. Both subjects showed increasing rates of responding over the remaining sessions occurring under CRF. However, Subject A showed only a s lig h t increase in rate during the CRF components. This increase, as shown in Fig. 2, was w ith in v a r ia b ilit y lim its already obtained during previous sessions by th is su b je ct. When one component of a two-component m u ltip le schedule is manipulated, changes sometimes occur in the constant schedule component. Such an in te ra c tio n was not observed. Changes in rig h t component response rates fo r a ll three subjects were only s lig h t and remained well w ith in the range of previous v a r ia b ilit y. Phase 7 E x tin c tio n -E x tin c tio n Subject A in Fig. 2 showed an increase in session to session v a r ia b ilit y compared to Phase 3 e x tin c tio n responding, but did not display a large o ve ra ll decrement in responding. In Session 63, i t appeared as though e x tin c tio n was occurring when the session response

33 25 ra+e dropped to approximately 254 per minute. However, th is reduction was only tra n s ie n t and the session rate returned to 315, 280, and 307 responses per minute fo r the last three sessions. Figure 6 shows the responses per minute occurring in each o f the 5 minute components of Phase 7 e x tin c tio n sessions fo r Subject A. During the th ird 5 minute component in Session 65, Subject A em itted 13 responses per minute less than in the fourth r ig h t component. The same re la tio n s h ip existed between these response components in Session 66, but there was only a one response per minute d if f e r ence. I n i t i a l l y, large drops in response rates during both le f t and rig h t components occurred w ith Subjects B and C. N either subject exhibited lower rates of responding in the VI-CRF h is to ry component than they showed in the simple VI h is to ry component. In fa c t, both Subject B, in Fig. 3, and Subject C, in Fig. 4, show c o n s is te n tly higher rates during the 10 minutes of e x tin c tio n responding in the le f t components. Subject B, in Fig. 7, did not show a systematic sequential decrease in responding during the last two components of Sessions 40 and 43. Response rates during the th ir d components in these sessions were respectively 9 and 3 responses per minute less than in the fourth components. During the last two components in Session 18, Subject C did not display a system atic sequential decrease in responding. Figure 8 shows the rate of responding fo r Subject C in component three to be two responses per minute below th a t of component fo u r. In Session 19,

34 26 Fig. 6 Responses per minute em itted by Subject A during each of the 5 minute components occurring during Phase 2 e x tin c tio n.

35 27 G B >- >- DC DC 0 O H f - CO CO X X u_ JQ DC i <-> > 1 in i > MINUTE COMPONENTS

36 Fig. 7 Responses per minute emitted by Subject B during each of the 5 minute components occurring during Phase 7 e x tin c tio n.

37 29 I > - > - t r a : o o H I CO CO X Lice 0 1 in i > X ID i > to CM CO 111 CO 5 MINUTE COMPONENTS O 00 T o st- N m / S3SN0dS3y

38 30 Fig. 8 Responses per minute em itted by Subject C during each of the 5 minute components occurring during Phase 7 e x tin c tio n.

39 31 0> CO LU CO VI-15- CRF HISTORY >- DC O h CO ao i > CD CO UJ CO ro MINUTE COMPONENTS tf) CVJ 'NIIA! / S3SN0dS3H

40 32 the response rate fo r component two was one response per minute below th a t of component three. In th is case, i t was a rig h t response component in which there was no system atic sequential decrement of responding in e x tin c tio n. DISCUSS ION The h is to ry of CRF given to the le f t response component was r e la tiv e ly sh o rt in re la tio n to its VI h is to ry. The primary reason fo r th is was the fa c t th a t during 10 minutes of CRF responding, subje c ts could obtain fa r more re in fo rc e rs than could be consumed in a 24 hour period. The p o s s ib ility of s a tia tio n was somewhat attenuated w ith Subjects B and C who ty p ic a lly gave away portions of t h e ir candy, cookies, e tc. to t h e ir frie n d s. When one component was placed on CRF while the other remained under a VI-15 schedule, there was the p o s s ib ility th a t some s o rt of induction or co n tra st in te ra c tio n e ffe c t could occur (H itzin g and S chaeffer, 1968). If the response rate in the VI-15 component had flu ctu a te d in the same d ire c tio n as the response rate in the CRF component, i t would have been an example of induction. Contrast would have occurred i f the VI-15 response rate flu ctu a te d in the opposite d ire c tio n as did the responding which had been placed on CRF. N either of these phenomena were in evidence fo r any of the subjects. Only Subject C showed a s lig h t decrease in the VI-15 component over a period of three sessions. However, th is trend remained well w ith in the lim its of previous v a r ia b ilit y.

41 1+ is in te re s tin g th a t Subject A displayed no system atic decrement in response rate during e ith e r Phase 3 or Phase 7 e x tin c tio n. From these data, one might conclude th a t points were not e ffe c tiv e re in fo rc e rs. of responding. However, a DRO schedule e ffe c tiv e ly reduced his rate This event stro n g ly suggested th a t the points were a re in fo rc e r fo r Subject A. At the end of the experiment, when asked why he had not stopped responding in e x tin c tio n, the subject explained th a t he was instructed to push the switches when the lig h ts came on and he simply did what he was to ld to do. This study did not fin d any large differences in response rates between components during Phase 7 e x tin c tio n. The fa c t th a t the simple VI h is to ry rates of responding were generally lower during e x tin c tio n is probably not ju s t a function of the reinforcem ent h is to ry fo r responding in th a t component. E xtin ctio n response rates would be expected to be higher in th is component because e x tin c tio n t y p ic a lly involves an o ve ra ll progressive decrease in response rate. This phenomena is presented g ra p h ica lly in Fig. 5. Since Toombs, (1961), L ike ly (1958), and Spradlin (1962) employed between-subjects experimental designs, they could not have reported th is with in subject sequential e ffe c t. A fin e r analysis of response rates in e x tin c tio n during both VI and VI-CRF components was displayed in Figs. 6, 7 and 8. Several times the response rate in the VI-CRF h is to ry component was s lig h tly lower than in the fo llo w in g VI h is to ry component, but these d i f f e r ences were not of s u f f ic ie n t magnitude or frequency to be detected when the data were p lo tte d as a to ta l rate of responding fo r the

42 34 VI and VI-CRF components per session as in Figs. 2, 3 and 4. By shortening the duration of the response components, the number of components, and using a th in n e r VI schedule, increasing i t is possible th a t e x tin c tio n responding would become less v a ria b le and more s e n s itiv e to any sm aller e ffe c ts of the CRF h is to ry. Nevertheless the re su lts of the present experiment provide no basis fo r the general supposition th a t continuous reinforcement of a response which has a h is to ry of in te rm itte n t reinforcement would weaken e x tin c tio n respondi ng.

43 35 References Ay Mon, Teodoro and M ichael, Jack. The P s y c h ia tric Nurse as a Behavioral Engineer. Journal of the Experimental Analysis of Behavior, 1959, 2_, A zrin, N. H. and Holz, W. C. Punishment. In Werner K. Honig (Ed.) Operant B ehavior: Areas of Research and A p p Iic a tio n. New York: A ppieto n-c entury-c rofts, 1966, Pp F le sh ie r, M. and Hoffman, H. S. A Progression fo r Generating V a ria b Ie -ln te rv a I Schedules. Journal of Experimental Analysis o f B ehavior, 1962, Vol. 4, P H itz in g, Wade and Schaeffer, Robert W. Behavioral Contrast: Schedule of Reinforcement as a Possible L im itin g C ondition. Psychological Reports, 1968, 22, K e lle r, F. S. and Schoenfeld, W. N. P rin c ip le s of Psychology. New York: A ppieton-c entury-c rofts, 1950, P. 89. L ik e ly, F. A. R elative resistance to e x tin c tio n of aperiodic and continuous reinforcem ent separately and in combination. Journal of General Psychology, 1958, 58, Skinner, B. F. The Behavior of Organisms. New York: A ppieton-c entury-c rofts, 1938, P S pradlin, Joseph E. E ffects of reinforcem ent schedules on e x tin c tio n in severely m entally retarded c h ild re n. American Journal of Mental D e ficie n cy, 1962, Vol. 66, No. 4, Toombs, S. E. F a c ilita tio n of E xtin ctio n A fte r Variable Interval Reinforcement. An unpublished Masters' Thesis, August, 1961, U n ive rsity of Houston. W illiam s, Carl D. The E lim in a tio n of Tantrum Behavior by E x tin c tio n Procedures. In L. P. Ullmann and L. Krasner (E ds.), Case Studies in Behavior M o d ific a tio n. New York: H o lt, R inehart, and Winston, 1965, Pp