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operant chamber
operant chamber

operant chamber

Date1960
Inventory Number2008-1-0003
ClassificationOperant Conditioning Chamber
Subject
    Cultural Region
      Place of Origin
        Place of Use
          Dimensions27 x 26 x 44 cm (10 5/8 x 10 1/4 x 17 5/16 in.)
          rat chamber: 18.5 x 19.5 x 29 cm (7 5/16 x 7 11/16 x 11 7/16 in.)
          Material
            Accessoriesmanual: <i>Laboratory Studies in the Analysis of Behavior</i> by Homme and Klaus (1957)
            Bibliography
            DescriptionSimple, manually controlled "Skinner box" used in Professor L. Dodge Fernald's introductory experimental psychology courses at Bowdoin College.

            The box has a steel floor, three steel sides, and one side made of plexiglas to allow observation. The top, also of plexiglas, can be slid in and out of place to allow a student to place the rat inside; it also has a number of air holes. The inside dimensions of the chamber have been reduced by the installation of two inner walls; these were not part of the original box as manufactured, but were added later by shop technicians or instructors -- the original walls and plexiglas were scored to align the new screw holes.

            One wall of the chamber has three simple controls (the other walls are bare): a small light placed high up, with a long electrical cord terminating in an ordinary two-prong plug; a simple T-shaped lever placed so the rat can reach it; and a water dipper. The lever and dipper have been modified slightly. The student's end of the lever has been wrapped in masking tape, possibly to muffle the thump of lever against light box when the rat pushed it down all the way, and there is also a small strip of metal fastened with gauze tape to the student's end of the lever, to counterbalance the bar. At the point where the dipper contacts the floor, a small weight has been attached to the dipper with similar gauze tape.

            The box came with a manual, Laboratory Studies in the Analysis of Behavior by Homme and Klaus (1957), which Fernald says was not used in his course but does a very good job of illustrating how such a box would have been used. He encountered the book after he had already been teaching his course for several years, and was pleased to see how similar his course was to the book.

            There is also a three-page description of the chamber, written by Fernald, which is very helpful.
            Signedon small plaque at lower right corner of end of box: SCIENTIFIC PROTOTYPE MFG. CORP. / NEW YORK 27, N.Y.
            FunctionSince it was designed for instruction in Professor L. Dodge Fernald's classroom rather than research, this box is different from others in the collection in several important ways.

            It has none of the cumulative recorders, automatic food dispensers, and programmable stimuli that accompany the research boxes. Students in Fernald's class worked in pairs. Reinforcements were administered via the brass dipper; bar-presses were recorded by making hash marks on paper; and the light was operated by plugging the cord into a nearby outlet. (Professor Fernald recalls that some boxes had switches on the light cord, which made life easier, but some unfortunate students with boxes like this one had to station one partner by the outlet to plug and unplug the cord.)

            One student, designated the recorder, made a hash mark on paper every time the rat pushed the bar down far enough -- "enough" being operationalized, per Fernald, as a thump when the end of the lever hit the bottom of the light box. As noted in the description, this box's lever has been modified: The student's end is covered with masking tape, possible to muffle the thump, and there is also a small strip of metal fastened to the end with gauze tape, to counterbalance the bar. Fernald said this was to slow down the rat's responses a little bit.

            The reinforcer used here was not food pellets but drops of water, which were used because they are faster to administer (a rat can drink a drop of water faster than it can eat a pellet). A student administered water via the dipper, which is a length of metal rod, possibly brass, bent in three places so that one end forms a handle outside the box and the other end, which is concave, forms a simple ladle. A plastic water trough sat beneath the floor at the dipper end of the box; when the student moved the dipper handle, the other end scooped up a drop of water and lifted it up into the rat's chamber through a small hole in the floor. When the dipper reached the "up" position, part of it would hit the steel plate of the floor and make a click, which served as a secondary reinforcer (as with click-training). The water trough could be slid out silently so that students could record how the rat's behavior changed during the period known as "extinction," when the secondary reinforcer, the click, continued without the primary reinforcer, the water. The rat would gradually stop associating the click with the water. (Though the behavior would appear again, briefly but strongly, after a rest period, a phenomenon known as "spontaneous recovery.")

            There is a small and movable brass counterweight on the handle of the dipper, which Fernald thinks may have been used to set the dipper in one position, up or down, during periods when the interval between reinforcements was long.

            The "toys" in the box would have been used by the students to demonstrate how a series of stimuli and responses could be chained together, so that the rat could gradually be trained to, for example, first roll the marble, then nose the flag, then touch the watch, then press the lever, and only then get the water. Students were encouraged to be creative in scripting such sequences. These toys are all "original," meaning they were chosen and used by students in Fernald's class, with the exception of the watch, which was a throwaway watch he wanted to add to the box because it "made for a better story"; see his brief essay for details.
            ProvenanceL. Dodge Fernald, Jr.
            Historical AttributesUsed from 1961 to 1967 to give students hands-on experience with operant conditioning in Professor L. Dodge Fernald's introductory experimental psychology course at Bowdoin College. The box was already in Bowdoin's inventory when Fernald was hired; after his interview in 1961 he brought one of these boxes back to Philadelphia, where he was living at the time, in order to teach himself how to use it since he had never taught experimental psychology before. The inner walls were installed before Fernald arrived at Bowdoin, he said.
            operant chamber for rats for use with touch-screen monitor
            National Institute of Mental Health
            Date: circa 1998
            Accessories: computer (2004-1-0403b); computer screen with mask (2004-1-0403c); plus a control box; spare Plexiglas touchscreen mask; food pellet distributor
            Object number: 2004-1-0403a
            operant chamber for a rat
            Ralph Gerbrands Company
            Date: 1960-1970
            Object number: 1999-1-0051
            Marconi Victor course in wireless telegraphy (phonograph records)
            Victor Talking Machine Company
            Date: circa 1918
            Accessories: carton
            Object number: WJ0144
            2004-1--0403c
            Mark G. Baxter
            Date: 1998
            Object number: 2004-1-0403c
            geological chart: Terrains et Roches composant l'ecorce du Globe
            Henri G. Galeotti
            Date: 1830-1858
            Object number: 1998-1-1450
            wall chart, "No I, PROPERTIES OF BODIES"
            W & A. K. Johnston, Ltd.
            Date: c. 1872
            Accessories: rectangular and round wood stretchers
            Object number: 2008-1-0308a
            Portable darkroom closed for travel.
            Richard W. Thomas
            Date: circa 1861
            Accessories: bottle and beaker (1998-1-1634a); hydrometer and manual (1998-1-1634b)
            Object number: 1998-1-1634
            geological chart: État du Globe a ses Différens Ages
            Établissement Géographique de Bruxelles
            Date: 1830-1862
            Object number: 1998-1-1445
            astronomical regulator, no. 103
            Ballou Manufacturing Company
            Date: 1880-1890
            Object number: 1997-1-0515
            B&L BH8 laboratory compound microscope
            Bausch & Lomb Optical Company
            Date: circa 1910
            Accessories: objectives with original canisters (3): 1.9 mm 1.30 n.a., 4 mm 0.65 n. a.,16 mm 0.25 n. a.; oculars (2): 5, 10; immersion oil bottle; standing case with key
            Object number: 1304
            arithmometer (arithmomètre)
            Thomas de Colmar
            Date: 1850-1870
            Object number: 1997-1-0249