observing ben wyckoff: from basic research to … · wyckoff started his academic career as a...

Observing Ben Wyckoff: From Basic Research toProgrammed Instruction and Social Issues

Rogelio Escobar and Kennon A. LattalWest Virginia University

L. Benjamin Wyckoff’s seminal contributions to both psychological theory and application arethe subject of this review. Wyckoff started his academic career as a graduate student at IndianaUniversity, where he developed the observing-response procedure under the guidance of B. F.Skinner and C. J. Burke. At the University of Wisconsin–Madison, Wyckoff refined hismathematical theory of secondary reinforcement. This theory was the impetus for his creation ofan electronic simulation of a rat running a T maze, one of the first ‘‘computer models’’ oflearning. Wyckoff next went to Emory University, leaving there to help create two of the mostsuccessful companies dedicated to the advancement of programmed instruction and teachingmachines: Teaching Machines, Inc. and the Human Development Institute. Wyckoff’sinvolvement in these companies epitomizes the application of basic behavior-analytic principlesin the development of technology to improve education and human relationships. The emergentpicture of Wyckoff is that of a man who, through his research, professional work in educationalapplications of behavioral principles, and active involvement in the civil rights movement of the1960s, was strongly committed to applying behavioral science to positively influence humanbehavior change.

Key words: Benjamin Wyckoff, observing responses, conditioned reinforcement, teachingmachines, programmed instruction, human relationships, diversity issues, client-centeredtherapy

Lewis Benjamin Wyckoff, Jr., Bento friends and colleagues, was born in1922 in Niagara Falls, New York. Hedied at age 84 on June 6, 2007, at St.Simons Island, Georgia. He is per-haps best remembered among behav-ior analysts as the creator of theobserving-response procedure. In hisdoctoral dissertation he noted that,‘‘We shall adopt the term ‘observingresponse’ (RO) to refer to any re-sponse which results in exposure tothe pair of discriminative stimuliinvolved’’ (Wyckoff, 1951b, p. 1).

Many behavior analysts are famil-iar with the above statement, becauseWyckoff’s observing-response proce-dure is still widely used for investi-gating conditioned or secondary re-inforcement (hereafter, conditionedreinforcement) (e.g., DeFulio &Hackenberg, 2008; Escobar & Bru-ner, 2009; Fantino & Silberberg,2010; Lieving, Reilly, & Lattal,2006; Pessoa, Huziwara, Perez, En-demann, & Tomanari, 2009; Shahan& Podlesnik, 2008).

The first author is now at the NationalAutonomous University of Mexico and wassupported by a postdoctoral fellowship award-ed by the PROFIP of DGAPA-UNAM. Thispaper was possible thanks to the recollectionof many contributors to whom the authors areindebted: Estelle Wyckoff and Andrew Weisk-off (Benjamin Wyckoff’s family); John Cottonand Richard Atkinson (Indiana University);Lewis Gollub (Harvard University); BernardPyron and H. Philip Zeigler (University ofWisconsin); Stephen Kendall, Donald J. Levis,and William Deckner (Emory University);Donald Tosti, Roger Addison, Roger Stein-horst, Clifton Chadwick, and David Shields(Teaching Machines Inc.); Jerome Berlin,Gene Ruyle, and Schlomo Friedlander (Hu-man Development Institute); Lizette Royer(Archives of the History of American Psy-chology); Constance Carter (Library of Con-gress); and Kathleen Shoemaker (EmoryUniversity Manuscript, Archives, and RareBook Library).

Address correspondence to Rogelio Esco-bar, Laboratorio de Condicionamiento Oper-ante, Facultad de Psicologıa, UniversidadNacional Autonoma de Mexico. Av. Univer-sidad 3004, Col. Copilco-Universidad, Mexi-co, D.F. C.P. 04510 (e-mail: [email protected]), or to Kennon A. Lattal,Department of Psychology, West VirginiaUniversity, Morgantown, West Virginia26506 (e-mail: [email protected]).

The Behavior Analyst 2011, 34, 149–170 No. 2 (Fall)

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Wyckoff’s observing-response pro-cedure offered a means of demon-strating the acquisition and main-tenance of an operant, the onlyprogrammed consequence of whichis the production of discriminativestimuli, without altering the rate ofprimary reinforcement (for reviews,see Dinsmoor, 1983; Fantino, 1977).The procedure typically consists oftwo components alternating random-ly. During one component, responsesare reinforced according to an inter-mittent schedule (e.g., a variableinterval); during the other compo-nent, responses are not reinforced. Aresponse on a second operandumbriefly produces the stimulus associ-ated with the ongoing component(e.g., a green light during the rein-forcement component and a red lightduring the extinction component).The observing-response procedure isone of most useful methods forstudying conditioned reinforcement(see, e.g., Williams, 1994, for areview).

A year after he finished his doc-toral studies, the theoretical Part 1 ofhis dissertation was published inthe Psychological Review (Wyckoff,1952). The Social Sciences CitationIndex indicates that this article hasbeen cited in over 250 other researchand theoretical articles in psychology.The procedural details of the observ-ing-response procedure, which con-stituted Part 2 of the dissertation,were not published until 1969, how-ever, in the volume entitled Condi-tioned Reinforcement edited by Hen-dry (Wyckoff, 1969).

Designing the observing-responseprocedure is alone sufficient to secureWyckoff mention in any history ofthe experimental analysis of behav-ior. That seminal work, however,perhaps overshadowed his less well-known work in behavior analysisfrom the mid-1960s that invites theattention of an even broader audi-ence of applied behavior analysts,educational technologists, educators,computer enthusiasts, and even civil

libertarians. Wyckoff’s journeythrough behavior analysis may belikened to the journey described bySkinner in ‘‘A Case History inScientific Method’’ (1956): an induc-tive approach in which the scientistfollows the data wherever they hap-pen to lead. This approach in Wyck-off’s career is an instructive counter-point to the numerous examples ofgaps among basic research, appliedresearch, and service delivery aspectsof behavior analysis (e.g., Michael,1980; Pierce & Epling, 1980). Thepurpose of this historical review is totrace the course of Wyckoff’s journey.

EARLY ACADEMIC LIFE ANDINDIANA UNIVERSITY

Wyckoff attended Antioch Collegefrom 1941 to 1947, having completed5 years of premed courses. Followinggraduation, he applied to HarvardMedical School, but he changed hismind and pursued a PhD in psychol-ogy instead. His wife, Estelle, notedthat he learned of Skinner’s work anddecided to study under his supervi-sion at Indiana University (E. Wyck-off, personal communication, March22, 2009).

According to J. Cotton (personalcommunication, February 24, 2009),who became friends with Wyckoff atIndiana, he and Wyckoff took anintroductory course on the topic ofthe experimental analysis of behaviorwith Skinner, circa 1947. The goal ofthe course was to familiarize gradu-ate students with Skinner’s 1938book, The Behavior of Organisms.

Even before Skinner arrived inBloomington in 1945, Indiana Uni-versity was fertile ground for behav-iorism and behaviorists. Under theinfluence of J. R. Kantor, W. N.Kellogg, and R. C. Davis, graduatestudents were well acquainted withlearning theories. As part of the taskto rebuild the Department of Psy-chology after the war, Kantor at-tracted Skinner to Indiana University(Hearst & Capshew, 1988). In the

150 ROGELIO ESCOBAR & KENNON A. LATTAL

following years, the addition to thefaculty of W. O. Verplanck, W. K.Estes, S. W. Bijou, D. G. Ellson, C. J.Burke, W. O. Jenkins, and I. J.Saltzman favored the melding ofdifferent behavioristic approaches tothe study of learning.

The origins of behavior analysisare closely tied to Bloomington,Indiana. The first and second Con-ferences on the Experimental Analy-sis of Behavior were held there, atIndiana University, in 1947 and 1948(see Dinsmoor, 1987). Wyckoff maybe seen in a photograph of theattendees of the first conference (seep. 456 of Vol. 5 of the Journal of theExperimental Analysis of Behavior[JEAB]; see also Hearst & Capshew,1988; Skinner, 1979). Wyckoff alsoattended the third conference atColumbia University, where a pho-tograph (Dinsmoor, 1990) shows himstanding next to another graduatestudent, Lloyd Homme, who alsowas one of his closest friends inBloomington. In the ‘‘Conferenceon the Experimental Analysis ofBehavior Notes’’ dated February 1,1949, they appeared as coauthors ofone presentation on the effects ofdeprivation on feeding behavior. Aswill be described below, their collab-oration and friendship continued formany years.

Wyckoff made a good impressionon Skinner. For one thing, he sharedSkinner’s passion for building appa-ratus. For another, he and Skinnerhad mutual research interests. Duringhis time at Indiana, Skinner wasworking on the experiments onmatching to sample described inSkinner (1950, 1979, p. 320). Skinnerdescribed how these experiments,using pigeon boxes displaying threeresponse keys, led to studies ofattention and abstraction or conceptformation. It is unclear on which ofthese experiments Skinner and Wyck-off collaborated. Based on Skinner’snotes in his autobiography (1983,p. 37), however, before Skinner leftIndiana in 1948, Wyckoff was work-

ing with him on experiments ondiscrimination in which reinforce-ment was contingent on two proper-ties of the stimuli. Skinner’s notes(1983, p. 415) suggest that the ratio-nale for these experiments was tostudy concept formation.

From his interactions with Skinnerat Indiana, Wyckoff earned an invi-tation to work with Skinner atHarvard during the summer of1950. In Cambridge, Wyckoff imme-diately became good friends withCharles Ferster, with whom he spentmany evenings playing music, some-times joined by Skinner. Wyckoffwas a fine pianist (E. Wyckoff,personal communication, June 18,2009).

According to Skinner (1983, pp. 37,415), during his time at Harvard,Wyckoff continued their research onconcept formation that was started atIndiana. It was supposed to employ asingle-key procedure in which rein-forcement would be contingent ontwo properties of the stimuli. Skinnerwanted Wyckoff to present fourstimuli (red flashing, red continuous,green flashing, and green continuous)to test for the formation of theconcepts of color and flashing ornot flashing. Wyckoff, however, ap-parently modified the procedure.Skinner (1983) observed in his auto-biography that ‘‘Ben Wyckoff was hisown man and did the work his ownway’’ (p. 415). Although the details ofWyckoff’s modifications to Skinner’sdesign are lost, Skinner does refer toWyckoff’s experiments in ‘‘The Sci-ence of Learning and the Art ofTeaching’’:

In a special case first investigated by L. B.Wyckoff, Jr., the organism responds to onestimulus where the reinforcement consists ofthe clarification of the stimulus controlling asecond response. The first response becomes,so to speak, an objective form of ‘‘payingattention’’ to the second stimulus. In oneimportant version of this experiment, as yetunpublished, we could say that the pigeon istelling us whether it is ‘‘paying attention’’ tothe shape of a spot of light or to its color.(Skinner, 1954, p. 89)

OBSERVING BEN WYCKOFF 151

According to L. Gollub (personalcommunication, February 1, 2008),the experiments on ‘‘attention’’ toshape and color, which Skinnersuggested were started by Wyckoff,continued at Harvard, and culminat-ed in Reynolds’s (1961) paper onattention in the pigeon. The similaritybetween Reynolds’s procedures andthe experiments that Wyckoff con-ducted in Skinner’s lab, in terms ofthe use of two-element discriminativestimuli, is notable.

Skinner (1950) stated that he haddifficulty training pigeons to produceand ‘‘attend’’ to a sample stimulusin his experiments on matching tosample. It seems reasonable to con-clude that Skinner started to discusswith Wyckoff, while he was atHarvard, the idea of measuringresponses that make contact withthe discriminative stimuli, the line ofresearch that culminated in Wyck-off’s doctoral dissertation. This sug-gestion is supported by the fact that afew years later Wyckoff acknowl-edged Skinner in his dissertation forhis help in the experiments that led tothe observing-response procedure.

Although Skinner invited Wyckoffto stay at Harvard to complete hisstudies, Wyckoff decided to return toIndiana University. According toEstelle Wyckoff, the primary reasonfor returning to Indiana was thatWyckoff knew that Skinner’s domi-nant personality would compel himto be devoted exclusively to Skinner’sreinforcement theory. For Wyckoff,as he learned at Indiana, reinforce-ment theory was only a part of whatare generally referred to as learningtheories, and he wanted to take whathe thought was useful from all ofthem. For example, as his subsequentresearch showed, he was not pre-pared to abandon the mathematicaldescriptions of learning. To avoid aconfrontation with Skinner, however,when he had to explain his reasonsfor leaving, he used his wife as anexcuse. Skinner was not pleasedabout Estelle’s pressure on her hus-

band and confronted her. She, how-ever, had no idea what Skinner wastalking about (E. Wyckoff, personalcommunication, June 18, 2009).

When Wyckoff returned to Indi-ana, he obtained his MA with W. K.Estes. He was always grateful for thehigh standards in writing imposed byEstes (E. Wyckoff, personal commu-nication, March 22, 2009). Given theinfluence of Estes and the training inquantitative analysis in his courseswith the recently hired Cletus J.Burke, it is not surprising that hismaster’s thesis focused on the quan-titative relation between the numberof lever presses during extinction andthe number of reinforcers deliveredduring conditioning (Wyckoff, 1950,1951a). Wyckoff chose Burke to behis adviser for the doctoral disserta-tion. Burke obtained his PhD in 1949at the State University of Iowa withKenneth Spence (Burke, 1949). Hehad solid training in statistics and inthe Hull-Spence theories. Verplanckdescribed Burke in 1950 as the beststatistician he knew, a very good andcreative experimental psychologist,and as an informal but effectiveteacher.1

Wyckoff’s doctoral dissertation re-flected well his two main influences:Skinner’s experimental analysis ofbehavior with free-operant proce-dures and Burke’s strong focus onquantitative methods, anchored inSpence’s theory of discrimination.Wyckoff’s observing-response proce-dure allowed recording of a responsethat exposed an animal to discrimi-native stimuli. Recording these re-sponses, which were characterized atthe time as ‘‘attending’’ and weredescribed previously by Spence(1940), was crucial in the continuityvs discontinuity debate in discrimina-tion learning (see also Spence, 1945).

1 Letter of recommendation to Edwin B.Newman. January 10, 1950. William S.Verplanck Papers, Box M1878, Folder 4.Archives of the History of American Psychol-ogy, University of Akron.


Wyckoff primarily was interested inSpence’s continuity theory, but hetook the explanation for the occur-rence of observing behavior fromSkinner’s (1938) The Behavior ofOrganisms: Discriminative stimulican function as conditioned reinforc-ers. This double influence of Skin-nerian and Hullian-Spencerian tradi-tions was central in the subsequentpositive impact of Wyckoff’s observ-ing-response procedure.

Wyckoff’s procedure was adoptedby researchers in the Hull-Spencetradition, like Perkins’s group, whichstudied observing behavior in mazes(Levis & Perkins, 1965; Lutz &Perkins, 1960; Prokasy, 1956). In anE maze, for example, an observingresponse is recorded when the animalruns to the side in which the color ofa small waiting chamber correlateswith the presentation or with theabsence of food instead of running tothe side in which the color of thewaiting chamber does not correlatewith the outcome.

The observing-response procedurewas used extensively by researchers inthe Skinnerian tradition like Kelleher(1958), whose research on response-produced stimuli appeared in the firstissue of JEAB, and Holland, where itappears in his vigilance tasks (Hol-land, 1957, 1958). Also, Killeen (1982)suggested that Herrnstein’s experi-ments on conditioned reinforcement(Herrnstein, 1964) were at least par-tially inspired by Wyckoff’s proce-dure. Furthermore, the quantitativemodel describing observing responses,which was central in Part 1 of Wyck-off’s dissertation, appealed to behav-ioral researchers who were developingand extending mathematical theoriesof learning and attention (e.g., Atkin-son, 1961; Atkinson & Estes, 1963;Bush, 1965; Norman, 1968).

UNIVERSITY OFWISCONSIN–MADISON

After completing his PhD, Wyck-off accepted a position as an instruc-

tor at the University of Wisconsin–Madison. He and Estelle moved toMadison in 1951 (E. Wyckoff, per-sonal communication, March 22,2009). Psychology at the Universityof Wisconsin at that time was dom-inated by the strong presence ofHarry Harlow. The department fa-vored empiricism with a generalapproach to psychology and a strongemphasis on statistics (B. Pyron,personal communication, January18, 2009). Wyckoff had a strongbackground in statistics, but it isnot clear how his interests in behav-iorism and operant procedures werereceived by the department. L. Gol-lub (personal communication, Janu-ary 31, 2008) recalled that, in one ofWyckoff’s visits to the HarvardPigeon Lab when he was on thefaculty at Wisconsin, he mentionedthat he was given a broom closetunder the flight of the stairs as hisoffice. Whether this office assignmentwas a matter of space, as it was inmany departments of psychology, orsomething less benign is unknown.

During his tenure at Wisconsin,Wyckoff published three articles thatdealt with conditioned reinforcementand discrimination learning (Wyck-off, 1954, 1959; Wyckoff, Sidowski,& Chambliss, 1958). In his 1954paper, he used a linear-operatormodel to describe the change in reflexstrength as a function of the reinforc-ing value of the stimulus conditionspresented after the response. Hebased this model on the idea of thedual function of stimuli as discrimi-native and reinforcing (Dinsmoor,1950; Skinner, 1938). An interestingdetail of this paper is that he correct-ed his mathematical model aftertesting it with an electronic modelthat he constructed (see also Cor-deschi, 2002, pp. 169, 183; ‘‘GoodTurn Deserves Another,’’ 1953).

The electronic model was based ontimer circuits using vacuum tubes. Itsimulated choices in a T maze with orwithout a previous observing re-sponse. In the model, Wyckoff sim-


ulated four conditions that resultedfrom choosing to observe or not, andchoosing the reinforced or the unre-inforced side of the maze. Forexample, if a simulated observingresponse occurred in combinationwith choosing the reinforced side ofthe maze, the reinforcing propertiesof the stimuli on the next trialincreased by changing the voltage ina condenser via relay connections.This increased the probability of asimulated observing response on thefollowing trial. The experimenterrecorded the simulated responses byilluminating different sequences offour lights that represented the tworesponses in the two choice phases2

(see also Minsky, 1961).Earlier electronic models of learn-

ing in mazes had been developed(e.g., Ross and Smith’s 1937 ‘‘robotrat,’’ Ross, 1938; Shannon’s 1951‘‘maze-solving rat,’’ Cordeschi, 2002;and Wallace’s, 1952, ‘‘maze-solvingcomputer’’), but Wyckoff was thefirst to consider the principles ofdiscrimination and conditioned rein-forcement in constructing such anelectronic model. Contemporarycomputer models of operant condi-tioning such as the ‘‘Skinnerbots’’(Touretzky & Saksida, 1997) andSniffy the Virtual Rat (Alloway,Wilson, & Graham, 2005) now rou-tinely incorporate these principles.

Wyckoff’s other accomplishmentsduring this time included a 1-yearfellowship, in 1955, at the Center forAdvanced Study in the BehavioralSciences at Stanford University(‘‘Faculty: Honored and Appointed,’’1955). From his work at the center,he refined his theory of conditionedreinforcement by addressing theasymmetry of the reinforcing andaversive properties of the stimuliproduced by observing (Wyckoff,1959; see Dinsmoor, 1983, for a

discussion). He also coauthored anumber of publications with col-leagues and students (Auerbach,Waisman, & Wyckoff, 1958; Pyron& Wyckoff, 1961; Sidowski, Wyck-off, & Tabory, 1956; Wyckoff &Page, 1954; Wyckoff & Sidowski,1955; Zeigler & Wyckoff, 1961). Hisinterest in apparatus again was dem-onstrated in his 1954 paper withPage. They described a grid foradministering electric shocks to rats.One problem with previous deviceswas that the rats could avoid theshock by standing on two bars thatwere on the same side of the electriccircuit. A few years before, Skinnerand Campbell (1947) designed thefirst device that avoided the problemby repeatedly changing the polarityof the bars (i.e., a shock scrambler).Rats could still detect the pattern ofchanges in the polarity in the bars,however (see Sloane, 1964, for de-tails). Wyckoff and Page’s device wasthe first modification to Skinner andCampbell’s scrambler that permitteda more rapid, uniform, and reliablepolarity alternation (see Azrin, Hop-wood, & Powell, 1967).

Wyckoff was also coauthor of apaper on the influence of punishmentand reinforcement in a minimal socialsituation (Sidowski et al., 1956),which received particular attentionfrom social psychologists (e.g., Col-man, 1995; Gergen & Barton, 1974).The experiment demonstrated thattwo participants can work togetherto produce reinforcement and reducepunishment for both of them evenwhen they are unaware of being in asocial interaction. This paper wasreprinted and discussed in McGinniesand Ferster’s volume on the rein-forcement of social behavior (Si-dowski, Wyckoff, & Tabory, 1971)and in Staats’s edited textbook onhuman learning (Sidowski, Wyckoff,& Tabory, 1964).

During Wyckoff’s last year atWisconsin, a generalized discontentwith the policies of the AmericanPsychological Association (APA) to-

2 The diagrams of the electronic model andthe list of parts are stored as DocumentADI4160 in the Library of Congress, Wash-ington, D.C.


ward experimental psychology led tothe creation of the PsychonomicSociety in 1959. The primary issuewas APA’s strong focus on profes-sionalization and applied psychologyat the expense of basic research (seeDewsbury & Bolles, 1995, for adetailed history of the PsychonomicSociety). The society started formallywhen a group of psychologists fromthe University of Wisconsin sentletters inviting W. K. Estes, F. A.Geldard, C. H. Graham, N. E. Miller,C. T. Morgan, W. D. Neff, K. W.Spence, S. S. Stevens, and B. J.Underwood to serve on the organiz-ing committee of the American Fed-eration of Experimental Psycholo-gists.3 Among the psychologists whosent the invitation letters, and whoshould be acknowledged for their rolein starting what would be called laterthe Psychonomic Society, were Ver-planck, who was at the time a visitingprofessor at the University of Wis-consin, and Wyckoff.

Wyckoff’s loathingofadministrativework and academic politics may havecontributed to his discontent at Wis-consin. According to Zeigler (personalcommunication, December 18, 2008),he has been described as neither prac-tical nor political enough to survive inthe academic ‘‘jungle.’’ E. Wyckoff(personal communication, March 22,2009) described him as ‘‘resistant toauthority and rebellious, introverted,andsomewhatofaloner.’’AccordingtoJ. Cotton (personal communication,February 15, 2009), another issue thatmay not have helped Wyckoff’s teach-ing career was his well known absent-mindedness. In a humorous example,Cotton recalled that Wyckoff kept anextra tie in the lab because wearing a tiewas mandatory while teaching. Onsome occasions, he apparently forgotthe tie he was wearing and put on a

second one, thereby showing up forclass wearing both ties simultaneously.

When Wyckoff was offered aposition of associate professor withtenure at Emory University in 1960,he accepted it without hesitation,leaving Madison with his wife andtwo sons, Daniel and Andrew (E.Wyckoff, personal communication,March 22, 2009). Despite their hav-ing talked only a few times, hepersuaded Stephen Kendall, whowas a talented graduate student atWisconsin, to apply to Emory andstudy with him. Kendall had taken afew undergraduate courses withDinsmoor at Indiana, but his gradu-ate assistantship at Wisconsin wasreduced essentially to training andtesting cats. Kendall’s impression wasthat this tedious task was unlikely tochange in the near future. As a result,he considered the invitation to trans-fer to Emory with Wyckoff a goodopportunity, and took it (S. Kendall,personal communication, March 7,2009).

EMORY UNIVERSITY ANDTEACHING MACHINES, INC.

The environment at Emory wascomplicated. On the one hand, it wasfavorable to conducting behavioralresearch (D. Levis, personal commu-nication, March 17, 2009). On theother hand, the political issuessurrounding the choice of a newdepartment chair were completelydisrupting (S. Kendall, personal com-munication, March 7, 2009). Appar-ently, an unspoken reason for hiringWyckoff at Emory was the need for anew chair of the department. Con-vincing Wyckoff to take the job,however, ended up being impossible(E. Wyckoff, personal communica-tion, March 22, 2009). Some monthslater, Charles C. Perkins joined thefaculty and took the chair position,but all the pressure exerted on Wyck-off in the previous months adverselyaffected his motivation to pursue anacademic career.

3 Letter. July 23, 1959. David Grant Papers,Box M1026, Folder: ‘‘Correspondence, 1942–1971.’’ Archives of the History of AmericanPsychology, University of Akron.


Wyckoff’s dislike of academic pol-itics and administrative work con-trasted with his profound curiosityand love of research. D. Levis (per-sonal communication, March 17,2009), who was at the time a graduatestudent of Perkins, remembered thatWyckoff spent hours peering into hisexperimental chamber to see what hispigeons were doing. He investigateddelayed reinforcement and supersti-tious behavior in pigeons, and startedto develop a procedure akin to asynthetic schedule of reinforcementthat generated different rates ofresponding without altering rein-forcement frequency (S. Kendall,personal communication, March 12,2009). None of his research conduct-ed at Emory, however, was pub-lished. Perhaps an important reasonfor this was that a new enterprise,teaching machines, proposed by hisold friend Lloyd Homme, becamemost appealing and seems to havedistracted him from his academicpursuits.

After obtaining his PhD at IndianaUniversity in 1953 under the super-vision of Estes (Hearst & Capshew,1988), Homme took a position at theUniversity of Pittsburgh. He laterwas invited to work with Skinner atHarvard in his teaching machineprogram in the late 1950s (Skinner,1983, p. 119). This invitation fol-lowed Skinner’s first presentation ofteaching machines at the Universityof Pittsburgh in 1954 (Skinner, 1954).One of the achievements of Homme’scollaborative work with Skinner wasthe development of instructional pro-grams to be used in teaching ma-chines (Tosti & Kaufman, 2007). Theprograms ultimately would becomethe most important element in theteaching machine movement, farmore important than the iconichardware. From his work with Skin-ner, Homme learned that the pro-grams were the key to makingteaching machines successful. Indeed,Tosti (in Tosti & Kaufman, 2007)observed that Homme was responsi-

ble for the design of instructionalprograms that could be presented inbooks rather than by machines.Although instructional devices hadbeen described by Pressey in the1920s (Pressey, 1926, 1927; see Ben-jamin, 1988), teaching machines re-ceived more public attention afterSkinner’s (1954) influential paper‘‘The Science of Learning and theArt of Teaching.’’ In it, Skinnerdescribed a teaching device thatwould integrate the advances in theexperimental analysis of behaviorinto education. An important featureof the machine was that correctresponses were immediately rein-forced. The device presented pro-grammed material to individual stu-dents in the form of questions,exercises, or problems to be solved.The student was required to providean answer, which could be comparedimmediately with the correct re-sponse. In this way, each studentpracticed and was tested for his orher advances with the material to belearned and advanced at his or herown pace (see also Lumsdaine,1960b).

Skinner’s project attracted mediaattention (Skinner, 1983, p. 132) andoriginated the golden age of teachingmachines. Several companies startedto build and distribute teachingmachines. Some of them were moresuccessful in disseminating the tech-nology than Skinner, who had triedto distribute his machines with IBMbut could not close the deal (Skinner,1983, pp. 97–98). In 1959, Hommeand James Evans, one of his col-leagues from the University of Pitts-burgh, started their own company,Teaching Machines Inc. (TMI), todevelop and distribute teaching ma-chines and programmed books.Homme invited his old friends fromIndiana University, Robert Glaser,who also was a colleague at theUniversity of Pittsburgh, and Wyck-off to join them in the enterprise. ForWyckoff, it seemed to be a goodopportunity to put his acumen with


apparatus to practical use. In thebeginning, the company was head-quartered in Pittsburgh, but in 1960its headquarters moved to Albuquer-que, New Mexico (D. Tosti, personalcommunication, March 18, 2009).

Although the programmed instruc-tion industry was more concentratedon manufacturing teaching machinesthan on the programs for the devices(cf. Hechinger, 1966), TMI had theopposite agenda. As noted above, thefirst programmed instruction bookswere developed by Homme, alongwith Evans, and Glaser, at theUniversity of Pittsburgh, between1958 and 1960 (Glaser, Homme, &Evans, 1960; Lumsdaine, 1960b).

Dudley E. Cornell was hired byTMI to design what would becomeone of the most successful teachingmachines, the Min/Max (Cornell,1963). The name was short forminimum time/maximum learning.The original version, shown in Fig-ure 1, was made of metal, wasslightly larger than a typewriter andcould hold several pages of programsat a time. Through a window, thestudent could see the question, and aspace to write the answer was acces-sible in another window. After writ-ing the answer, the student could seethe correct responses and advance thepaper by pushing it with a pencileraser (Fine, 1962).

As TMI’s Chairman of the Board,Wyckoff made frequent trips toPittsburgh and later to Albuquerquefrom Atlanta to supervise the devel-opment of the programs for the Min/Max, which Tosti was in charge of

writing (D. Tosti, personal commu-nication, March 17, 2009). In a shorttime, TMI developed programs thatcovered topics in English, basic andadvanced mathematics, general sci-ence, languages, and music. Theassortment of programs, in combina-tion with a low-price teaching ma-chine, was the key to obtaining amajor distribution agreement withGrolier Inc. in November 1960.Grolier, which was one of the largestpublishers of encyclopedias in theU.S., used their 5,000 door-to-doorsalesmen to sell their encyclopediasets, the Book of Knowledge and theGrolier Encyclopedia (Klaw, 1962;‘‘The Truth About Those TeachingMachines,’’ 1962), with the addedincentive of receiving a complemen-tary Min/Max teaching machine andits programmed courses with anypurchase. Of course, it was alsopossible to purchase the machineand the programs independently ofthe encyclopedia sets.

By 1962, the Min/Max was mademore efficient and portable. Cornellhad designed two new versions of theMin/Max, also shown in Figure 1.The Min/Max II and III were madeof plastic and also about the size of asmall typewriter. Both models includ-ed two knobs on the sides that servedto advance the paper, but the Min/Max III was smaller and lighter(Cornell, 1966).

The advertisements of TMI pro-moting a low-cost teaching machineand a variety of programs can befound in many newspapers, educa-tion journals, and journals of that era

Figure 1. The picture shows from left to right, the Min/Max I, the Min/Max II, and the Min/Max III teaching machines.


focused on programmed instructionand behavior (e.g., American Behav-ioral Scientist, Grade Teacher, Har-vard Educational Review, Journal ofEducational Research, Journal of Pro-grammed Instruction, JEAB, TheAmerican School Board Journal,School Management, The ElementarySchool Journal, The New York Times,The Science Teacher, Today’s Educa-tion, among others). Even articles inthe general media described the‘‘revolutionary’’ teaching machinessold by TMI-Grolier (e.g., Klaw,1962; ‘‘The Teaching Machines,’’1960). In the first 2 years, TMI-Grolier sold over 150,000 teachingmachines, thereby becoming the mostsuccessful company devoted to pro-grammed instruction and teachingmachines (Klaw, 1962).

After the enormous success of theMin/Max and the company’s pro-grammed texts, TMI’s focus widenedwhen they offered a version of one ofSkinner’s most controversial gadgets,the air crib or baby tender (Skinner,1945/1972). In 1962, TMI beganselling its own version of Skinner’sair crib. The first model, named theIncu-crib, sold for $499. It was firstadvertised in the April 1962 issue ofJEAB. Skinner recalled in his auto-biography that he was asked tocomment on the crib, and he dislikedthe use of a plastic bubble because ofthe resonating acoustics (Skinner,1983, pp. 250, 251). A few monthslater the model was modified to makethe child more visible, improve theacoustics inside the crib, and lower itscost. After Skinner approved themodifications, the name of the cribwas changed to TMI-Aircrib and itsold for $250. D. Tosti (personalcommunication, March 17, 2009)recalled that he used this crib forthree of his children. An advertise-ment in the April 1963 issue of JEABportrays Jill A. Cornell, DudleyCornell’s daughter, as a happy childin a TMI-Aircrib.

Even before the Min/Max I was onthe market, Wyckoff began designing

a more sophisticated teaching ma-chine than the Min/Max series. Thefirst version of the machine, whichKendall helped construct, was con-trolled with five keys and presentedthe instructional material on a screen.The material, designed to teach chil-dren to read, was encoded on 35-mmslides. The slides showed incompletewords that the children were requiredto complete, one letter at a time.Various combinations of presses onthe five keys made up the alphabet.Only when the keystrokes matchedthe pattern in the film strip was theanswer coded as correct and the filmallowed to advance, presenting thecorrect letter on the screen.

The machine was labeled theWyckoff film-tutor and was firstavailable in 1959 (Kopstein & Shil-lestad, 1961). Wyckoff filed for apatent in 1960 (Wyckoff, 1964).Figure 2 shows a diagram of themachine based on the patent descrip-tion. A serious problem with the film-tutor was that, to use the machine,students had to learn a new code (i.e.,the key combinations for each letter)or use a conversion table. Wyckoffsubsequently designed improved ver-sions of the machine that included afull keyboard, eliminating the need tolearn a code. Two versions of themachine are also shown in Figure 2.The Wyckoff film-tutor solved twoproblems posed by the Min/Max.One was the amount of paper re-quired to present the programs. In asingle year, TMI consumed 1,000 tonsof paper in printing programs for theMin/Max (Donnelly, 1964). The oth-er problem was that the length ofeach question item was constrainedby the size of the window in the Min/Max. The Wyckoff film-tutor al-lowed the presentation of questionitems of various sizes (Lumsdaine,1960a).

At TMI, Roger Steinhorst was incharge of testing Wyckoff’s teachingmachine in the laboratories in NewMexico. Steinhorst recalled that itworked flawlessly (R. Steinhorst,


personal communication, March 19,2009). When TMI offered the Wyck-off film-tutor to Grolier for distribu-tion, Grolier executives refused (R.Steinhorst, personal communication,March 19, 2009). The executivesconsidered it to be too expensive. At$445, it was more than 20 times theprice of the Min/Max and weighedclose to 30 lb, too heavy to be carriedand sold door to door. AlthoughTMI advertised the Wyckoff film-tutor independently of Grolier (see,e.g., JEAB, 1961, Vol. 3, No. 4; 1962,Vol. 4, No. 1), it was never acommercial success. As might beexpected, Wyckoff was demoralizedby this outcome (J. Berlin, personalcommunication, March 18, 2009).Nevertheless, he developed a newmodel that presented an audibleversion of the instructional material.

Although the Wyckoff film-tutorwas not distributed by Grolier, theprogram inside the machine wastranslated into a TMI-Grolier pro-grammed course for the Min/Max(see Andrego, de Baca, Fullilove,Stranczek, & Wyckoff, 1962). Thepurpose of the program was to teachchildren reading skills more rapidlythan the conventional methods. In-stead of teaching the child to readletter by letter, the program firsttrained the child to match an imagewith a written word. This is similar to

the procedure of stimulus equivalenceused by Sidman (1971), more than10 years later, to teach children withdisabilities spoken and written words.Afterwards, using a procedure thatwas similar to the method of stimulusfading used by Skinner and Holland(e.g., Holland, 1960), parts of theword were removed. The child had tochoose or type the letters that com-pleted the missing segments of theword. After the word was trained, itwas incorporated into a sentence andthe procedure was repeated.

Based on the tests conducted atTMI, the time required to completethe course ranged from 15 to35 hours. Fine (1962, p. 77) witnessedthe success of the program with 4- to5-year-old children when he visitedTMI’s facilities. The program alsoproved to be successful for teachingchildren with learning disabilities toread (Malpass, Gilmore, Hardy, &Williams, 1963; ‘‘Teaching MachinesSpeed Progress,’’ 1964). Malpass etal. described how children with dis-abilities, using Wyckoff’s method,learned from two to six times morewords in 8 weeks than the childrenwho used the conventional classroommethods learned in 4 years. They alsosuggested that the method was aseffective as personalized instruction,with the advantage that it could beused with several children concur-

Figure 2. Three versions of the Wyckoff film-tutor. The diagram on the left shows the firstversion of the machine available in 1959. The machine was controlled with five keys, projectedthe material on a screen, and could be folded to make it portable (drawing based on U.S. PatentNo. 3,137,948). The middle drawing shows an improved version with a full keyboard. Thisdrawing was used as the TMI logo in commercial letters circa 1960 (William S. VerplanckPapers, Box M1887, Folder 1. Archives of the History of American Psychology, The Universityof Akron). The picture on the right shows the commercial version of the Wyckoff film-tutor(picture based on Malpass et al., 1963).


rently. The method used by Wyckoffalso had an impact on subsequentprograms developed by TMI. Forexample, D. Tosti (personal commu-nication, March 17, 2009) recalledthat he and Homme used it in acourse on letter writing.

Wyckoff’s method for teachingreading skills reached a diverse audi-ence. For example, James CookBrown discussed with Wyckoff theidea of using the modified film-tutorfor teaching Loglan, an artificialhuman language created by Brown(‘‘Eight Languages into One,’’ 1960).Loglan was created originally to testthe Sapir-Whorf hypothesis of lan-guage relativity. Brown’s idea was tocreate a language that could belearned independently of culturaldifferences and used a grammarbased on logical rules to eliminateambiguities (Brown, 1989). As will bedescribed below, Wyckoff’s methodalso came to the attention of RobertMoses, who planned to use it to teachilliterate African-American citizensfrom Mississippi to read (see sectionon Human Rights, below).

PERSONAL RELATIONS ANDPROGRAMMED INSTRUCTION:

THE HUMANDEVELOPMENT INSTITUTE

During his tenure at Emory,Wyckoff befriended Jerome Berlin, afaculty colleague in clinical psychol-ogy who, as a former student of CarlRogers at the University of Chicago,was a proponent of client-centeredtherapy. The two frequently dis-cussed their seemingly different ap-proaches to psychology. The mostfruitful of these interactions mayhave been around the topic of howpersonal relationships are main-tained. They both agreed that animportant element in such mainte-nance is communication. For Berlin,effective communication was accom-plished if the listener resembled aclient-centered therapist by showingempathy, congruence, and uncondi-

tional positive regard throughout hisor her interaction with the speaker.Wyckoff might have been expected todisagree with his colleague’s analysis,but instead, he carefully considered it(J. Berlin, personal communication,March 18, 2009).

Wyckoff went on to suggest thatcommunication can be analyzed as alearning process. People communi-cate on the basis of interlockingcontingencies (Skinner, 1957, p. 40);that is, speaking provides discrimina-tive and reinforcing stimuli for oneanother. A person communicateswith another if his or her verbalresponses are reinforced, and theperson stops communicating if hisor her verbal responses are ex-tinguished or punished. The threeelements Berlin considered to beimportant in achieving good commu-nication were analyzed by Wyckoff interms of positive reinforcement madecontingent on the verbal responses ofthe other person (see also Truax,1966a, 1966b, for a similar analysis).For Wyckoff, Rogers had identifiedreinforcers for adults’ verbal behav-ior (J. Berlin, personal communica-tion, March 18, 2009). Wyckoffnoted the complexity of such rein-forcers, because he firmly believedthat simply acknowledging what an-other person has to say is not aneffective way to increase communica-tion, even if it is contingent on averbal response. Deckner, one ofWyckoff’s graduate students at Em-ory, recalled that, as a joke, Wyckoffbuilt a small apparatus with a lever,that, when pressed, put up a little signthat said, ‘‘mmm hmm’’ (W. Deck-ner, personal communication, March6, 2009). Of course, no one expectedit to work.

Wyckoff went further in analyzingcommunication by pointing out that,if it involves a learning process, it canbe shaped. He reasoned that commu-nication could be systematicallytrained using programmed instruc-tion with two persons simultaneously(G. Ruyle, personal communication,


January 28, 2009; J. Berlin, personalcommunication, March 18, 2009).Wyckoff’s analysis was convincingenough to persuade Berlin to testthese ideas.

Several of Wyckoff’s studentsserved as participants in the firstexperiments in which spontaneous,and later preestablished, dialogueswere scrutinized (G. Ruyle, personalcommunication, January 28, 2009; J.Berlin, personal communication,March 18, 2009). Wyckoff and Berlinasked the participants to interact indyads (R. Addison, personal commu-nication, March 18, 2009). Theyassessed whether communicationwas improved by training each par-ticipant to make positive statementsabout the previous verbal response ofthe other. For subsequent experi-ments, they created examples ofappropriate and inappropriate dia-logues to serve as the basis fordiscriminating the correct and incor-rect verbal responses of the otherparticipant.

From these experiments, Wyckoffand Berlin derived systematic exam-ples of everyday dialogues and aseries of questions that they incorpo-rated into the first programmedinstruction course completed in 1963and designed to improve communi-cation in general relationships. Fig-ure 3 shows a fragment of the sixthedition of the manual (Human De-velopment Institute [HDI], 1972),which was designed to train eachindividual in a dyad to identify andreinforce the appropriate verbal re-sponses of the other individual. Inthis way, communication was expect-ed to improve in the absence of atherapist (see HDI, 1972). Theseideas, the program, and the resultsof several tests were presented at the1963 and 1964 APA conventions(Berlin & Wyckoff, 1964; Wyckoff& Berlin, 1963).

Wyckoff suggested that the manualbe edited by TMI and distributed byGrolier, but the executives of Grolieragain declined, noting that there was

no market for this product (D. Tosti,personal communication, March 17,2008). After this rejection, Wyckoffand Berlin turned to selling it on theirown. Wyckoff resigned as Chairmanof the Board of TMI to have moretime for the new project (J. Berlin,personal communication, March 18,2009), but he continued as a memberof the board of directors.

To embark on the new enterprise,both Wyckoff and Berlin also re-signed their faculty positions at Em-ory (Wyckoff was allowed to contin-ue as Kendall’s adviser until heobtained his PhD in 1963; S. Kendall,personal communication, March 7,2009). They rented a small buildingon West Peachtree Street in Atlanta,and founded their company. TheHDI was nominally started in March1962, but was not fully operationaluntil 1964. Figure 4 shows a part of abrochure describing the institute. Intheir new environs, they continuedtheir work on interpersonal commu-nication and, during 1963 and 1964they wrote the first programmedcourses to improve communicationin business and organizations, andothers to improve communication inmarriages. Figure 3 also shows afragment of the fourth edition of thelatter (HDI, 1970).

The strong emphasis on research indeveloping the training programsresulted in HDI becoming a greatsuccess. The training programs wereused to improve communication be-tween employees at United Airlines,Union Carbide, Lockheed Aircraft,Space Technology Laboratories,Baylor University Hospital, the So-cial Security Administration, WesternElectric, Procter and Gamble, volun-teers at the Atlanta Chapter ofHadassah, and graduate studentsat both the University of Alabamaand Georgia State College (Berlin &Wyckoff, 1964; Nicholson, 1963;Roalman, 1963).

Originally created to improve com-munication between two persons, thetraining programs started to gain


popularity as an alternative to coun-seling (cf. Eisenberg & Zingle, 1975;Ellis, 1966; Hickman & Baldwin,1971). Although Hickman and Bald-win found that HDI’s program forimproving communication in mar-riage positively influenced the atti-tudes of couples toward marriage, itwas not found to be more effectivethan personalized marriage counsel-ing. Nevertheless, it is worth notingthat Wyckoff and Berlin’s attempt touse psychological principles to traintwo persons simultaneously in im-proving their relationship was pre-ceded only by the creation of field

theory (Lewin, 1951) grounded t-groups in 1947 (Margulies & Raia,1978). Because of programmed in-struction, however, Wyckoff andBerlin’s manuals were more system-atic than t-groups, and could be usedin the absence of a therapist orobserver.

According to J. Berlin (personalcommunication, March 18, 2009),revising and developing new pro-grams at HDI, although successful,was exhausting. The first years of thecompany were difficult. Each pro-gram took months and even years todevelop. To survive, the work at HDI

Figure 3. Sample items from the General Relationship Improvement Program and ImprovingCommunication in Marriage (courtesy of Jerome Berlin). The first edition of the former waswritten by the Human Development Institute in 1963. The top three items were designed toteach people how to avoid punishing others’ verbal responses. The bottom three items were usedto teach people how to distinguish different situations in a marital relation that require differenttypes of conversations. The terminology was taken from Rogers’s client-centered therapy.


was transformed from a researchenterprise into a business, whichwas completely different from whatWyckoff and Berlin envisioned in thebeginning. Once again exasperatedby administrative issues, Wyckoff leftHDI in 1965.

About the same time, TMI wascollapsing. To begin with, teachingmachines were no longer thought tobe revolutionary devices (see Benja-min, 1988, for a history of teachingmachines). Criticisms raised by edu-cators had reduced the sales of both

Figure 4. Fragments of a brochure distributed by the Human Development Institute in 1964(courtesy of Jerome Berlin). The left section shows a teaching machine, designed by Wyckoff,that could be used to work through HDI’s manuals. The right section shows hand drawings ofJerome Berlin and Benjamin Wyckoff.


the Min/Max and programmedbooks. These criticisms had twothrusts. One was the dehumaniza-tion inherent in the use of machines.Although Skinner never intendedteaching machines to be a substitutefor teachers, this idea surfaced inthe general media as a threat to thedevelopment of creative and free-thinking students (e.g., Boroff, 1960;Gilmore, 1961). The other criticismpointed to the functionality ofteaching machines. It was suggestedthat teaching machines were nothingmore than expensive page turners(e.g., ‘‘The Truth About ThoseTeaching Machines,’’ 1962). Onesolid criticism was that the primitivestate of the technology available forteaching machines was limiting theevolution of programmed instruc-tion (Gilbert, 1960). TMI survivedfor some years because, by 1963, ithad shifted from the massive door-to-door teaching machine businessto developing custom courses forlarge organizations such as IBM,the U.S. Navy, and others. In 1963,Glaser left TMI to start an inde-pendent project, and Homme didthe same in 1964. In 1966, Evansand Cornell declared bankruptcy,and TMI’s assets were purchasedby Grolier.

By the mid 1960s, HDI also wasstruggling for survival. To be relievedof some of the administrative andfinancial issues, in 1967, Berlin wasforced to negotiate establishing HDIas a subsidiary of Bell & Howell(‘‘Bell-Howell Plans to Buy,’’ 1967;J. Berlin, personal communication,March 18, 2009). Bell & Howellcapitalized on the commonalitiesbetween the work done at HDI andRogers’s client-centered psychothera-py to develop and distribute audio-tapes designed to train groups ofpeople to interact effectively. Thesetapes were known as encountertapesin the Human Potential Movement(Klemesrud, 1970). The encounter-tapes were developed by Betty Ber-zon at the Western Behavioral Sci-

ences Institute in La Jolla, California.At that time, Rogers was a residentfellow at the Institute. Berzon movedto Atlanta to learn about pro-grammed instruction at HDI, fromwhich the tapes then developed (e.g.,Berzon & Solomon, 1964).

From interactions with employeesof several different companies, Berlinobserved that most often workplacestructures consisted of white supervi-sors and African-American or His-panic employees. He adapted HDI’sprograms to train the supervisors torelate to the employees with empathyand respect. The final product wasnamed the Sensitivity Kit or S-Kit(‘‘How to Succeed in Hard-CoreHiring,’’ 1968; James, 1969). Fried-lander, who arrived at HDI in 1967,recalled:

I was de facto leader of the team thatproduced the breakthrough product, calledthe S-Kit, which was used to train 130,000‘‘front-line supervisors’’ in industries aroundthe country to manage culturally differentworkers. In my opinion this was the true‘‘proof of concept’’ that prosocial behavior inadults could be systematically modifiedthrough the application of the principles ofoperant conditioning to the design of asequence of INTERACTIVE interpersonalexercises. (S. Friedlander, personal communi-cation, March 16, 2009)

Although HDI was enormously suc-cessful, Berlin decided, as Wyckoffhad earlier, that he had had enoughof administrative issues and left theorganization in the early 1970s. Theassets of HDI then were sold entirelyto Bell & Howell, and the institutewas moved to Chicago in 1974 (G.Ruyle, personal communication, Jan-uary 28, 2009). Given the debatesbetween Rogers and Skinner (e.g.,Rogers & Skinner, 1956) in whichthey each strongly asserted theirpoints of view of psychology, it issomewhat ironic that the work ofBerlin and Wyckoff, firmly anchoredin the principles of operant condi-tioning, was one of the starting pointsof the expansion of client-centeredtherapy into what became the Hu-


man Potential Movement (e.g., How-ard, 1970).

HUMAN RIGHTS

Wyckoff strove to treat everyonewith empathy, dignity, and respect(A. Weiskoff, personal communica-tion, March 22, 2009). His experi-ence of working in the early 1960sin industries in which African-Amer-ican employees had conflicts withwhite supervisors, and women werepaid only a fraction of what menearned, seemed to have stronglyaffected him. Several of the peopleinterviewed for this review corrobo-rated that Wyckoff was a passionatesupporter of human rights. He wasremembered for talking in the TMIoffices and among friends aboutthe successful civil rights protestsin the U.S. South in the 1960s, andof the importance of supportingboth the civil rights and the wo-men’s rights movements (D. Tosti,personal communication, March 17,2009). He was a member of theNational Association for the Ad-vancement of Colored People andhosted civil rights meetings at hishome (S. Kendall, personal commu-nication, March 7, 2009).

Holt (1965) described Wyckoff’srather unique involvement in theFreedom Vote Campaign in 1963.One of the political issues in Mis-sissippi was that in 1962, only 6.7%of Mississippi’s African-Americanadults were eligible to vote. Thereason was that voter eligibility de-manded the citizen meet a series ofstrict requirements (e.g., paying a polltax, fulfilling a residency condition,and passing a literacy test). The resultof such requirements was that, priorto the 1965 Voting Rights Act thatabolished them, an African-Ameri-can citizen’s opportunity to vote waslong delayed after the initial attemptto register. Holt noted that theStudent Nonviolent CoordinatingCommittee (SNCC) had considered

a plan to use programmed instructionto teach illiterate African-AmericanMississippians to read, thereby in-creasing the likelihood of their pass-ing the literacy test.

In the spring of 1963, Wyckoffand Robert Moses, field secretaryfor SNCC, met at Wyckoff’s homein Atlanta to discuss programmedinstruction. One of the topics washow reinforcement theory was usedin programmed instruction. Wyckoffreportedly noted the importance ofreinforcement immediacy, a princi-ple that ‘‘fermented within BobMoses’’ (Holt, 1965, p. 153). Holtdescribes how Moses came to con-ceptualize the many obstacles im-posed to register to vote as delays ofreinforcement.

As a result of the seed planted bythe discussion with Wyckoff, Mosesand his colleagues conceived a planto capitalize on the principle ofimmediate reinforcement. This in-volved establishing the 1963 Free-dom Vote Campaign in Mississippi.Holt (1965) noted that ‘‘The Free-dom Vote Campaign provided pos-itive and quick reinforcement’’(p. 153). It was as a result of this,according to Holt, that the Missis-sippi Freedom Democratic Party(MFDP) became established as analternative to the Mississippi Dem-ocratic Party. The former, followingthe principle of immediacy of rein-forcement, allowed any citizen tovote in its delegate elections, regard-less of whether they met stateeligibility requirements. The out-come was the massive media atten-tion that the MFDP received at the1964 Democratic National Conven-tion (see Smith, 2004) that resultedin the MFDP delegation receivingtwo at-large seats at the convention.Holt relates these outcomes directlyback to Wyckoff and the principleof immediacy of reinforcement. Theultimate outcome, according toHolt, was that the campaign dem-onstrated convincingly to the coun-try as a whole that African-Ameri-


cans in Mississippi were eager toexert their right to vote.4

LATER CAREER AND LEGACY

Although the enterprises in whichWyckoff was involved were success-ful in terms of their impact oneducation and improving humanrelationships, none of them werefinancial successes. Both TMI andHDI generated large profits, butmost of those profits were reinvestedto improve the machines and pro-grams. After Wyckoff left HDI, heworked as a systems analyst at theGeorgia Department of VocationalRehabilitation. He also obtained aposition as director of research andevaluation at the Georgia Depart-ment of Corrections, where latercreated a program used to keep trackof the records (A. Weiskoff, personalcommunication, March 22, 2009). Heretired from that position in 1987.

Even though Wyckoff had only afew doctoral graduates during hiscareer (Benjamin Pubols, H. PhilipZeigler, Jerry Tate, William Deckner,and Stephen Kendall), his influence isevident in their academic careers.Although Pubols was primarily in-volved in neuroscience, he conductedresearch on the parameters of rein-forcement (e.g., Pubols, 1958, 1960,1962). Zeigler’s primary interest wascomparative cognition. He modifiedWyckoff’s observing-response proce-dure such that a pair of stimuli waspresented after an observing responsewas emitted. In this way, he usedthe procedure as an analogue ofHarlow’s Wisconsin General TestApparatus (Zeigler, 1958; Zeigler &Wyckoff, 1961). Wyckoff directly

influenced Deckner’s work on educa-tional games based on programmedinstruction (Deckner, Deckner, &Davis, 2007), and Kendall’s signifi-cant contributions to the literature onconditioned reinforcement using theobserving-response procedure (e.g.,Kendall, 1965, 1972, 1973).

Wyckoff saw that all psychologists,independent of their particular orien-tation, are concerned with the studyof behavior. He was open to differentapproaches to the study of behavior,rather than being identified strictly asa Skinnerian, Hullian, or Spencian.This openness contributed to hisenduring contributions to both Skin-nerian and Hull-Spence theories ofbehavior through the observing-re-sponse procedure, his mathematicaltheory of secondary reinforcement,and programmed instruction. LikeSkinner, he was committed to theapplication of behavioral research toimproving the human condition. Hisactive involvement with TMI andHDI exemplifies the translation ofbasic principles of behavior analysisto applied settings and social issues.Wyckoff’s most important messagewas that, by leaving aside theoreticaland conceptual biases, it is possible tointegrate psychological knowledge toimprove the quality of peoples’ lives.

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