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Welcome to the Behavioral Apparatus Virtual Museum

Here you'll find a compilation of rarely seen photographs, background information, and links to information about scientific instruments large and small that have contributed to developing our understanding of the behavior of living organisms, from invertebrates to human beings.

There are 5 rooms in this virtual museum + a catalog archive. Each room displays instruments related to a specific aspect of the study of behavior. There are rooms, that display different types of environments for the study of behavior. One of these environments is the air crib, made famous by B. F. Skinner in a 1945 Ladies Home Journal article. Another room shows instruments used to measure behavior. Yet another shows devices for dispensing consequences – reinforcers and punishers. Among the devices in this room are those used in the 1950s and 1960s for dispensing candy and cigarettes to psychiatric patients studied on closed mental hospital wards of that era.

We invite you to wander where you like in the museum. Although you can’t touch the objects, you can click on various links that will take you deeper into the history, nature, and use of many of the instruments displayed.

The museum is indebted to the Association for Psychological Science (formerly the American Physiological Society) for providing its curator, Andy Lattal, with a summer teaching grant that made possible much of the preliminary work culminating in this display, and to Warren Street, who was instrumental in providing photographs of many of the items.

Room 1: Environments

All behavior occurs in an environment of some kind or another. The environment may be surrounded by the organism (an internal environment) or the organism may be surrounded by the environment (an external environment). Environments may be natural or constructed. Sometimes it is difficult to separate the two. Is a workspace one or the other? A classroom? A home setting? Many environments are created for specific purposes, such as minimizing distractions and optimizing control by the features of interest to an experimenter, or parent or therapist. The air cribs shown here were designed to optimize comfort for infants and ease the burden of child care maybe a little for caregivers. Step inside...

Room 2: Observation & Measurement

Observation is the most basic feature of any science, from astronomy to zoology. One way of making observations is directly, through actual visual contact with the phenomenon either with or without an instrument to aid in the observation. Another way of making observations is indirectly, by using an instrument to actually record instances of the phenomenon. Often the two methods are used together. In this room you will find instruments used in behavior analysis to make both direct and indirect observations. 

One dimension of observation is measurement. It is possible to have observation without measurement, but not to have measurement without observation. In a way, measurement is one outcome of observation. This room houses exhibits of instruments used to measure behavior with differing degrees of precision. Step inside...

Room 3: Presenting Stimuli

Stimuli are defined both structurally, in terms of their form, and functionally, in terms of their effects on behavior. A commonly studied type of stimulus in behavior analysis is a discriminative stimulus, an SD, or, as it is spoken, “ess-dee.” A discriminative stimulus sets the occasion for a response to be reinforced, at least intermittently.

The types of events used in the laboratory as discriminative stimuli are most often lights and sounds. Lights and sounds can be arranged in a variety of configurations and combinations, limited only by the availability of apparatus to present and control these stimuli. Lights and sounds, of course, are by no means the only types of stimuli used and studied. An example of the variety of events that have been studied as stimuli is by an experiment conducted by Millard (1979). A pigeon was placed on either side of a clear plastic partition such that they could see one another, but physical contact was not possible. The response key of the model pigeon was shielded such that the observer pigeon could see the model but not the key. When the model pigeon’s key was red, rapid key pecking was reinforced and when it was green, the absence of key pecking was reinforced. The observer pigeon’s key was always white. However, two conditions were in effect. When the model’s key was one color, pecking by the observer was reinforced and when it was the other color, pecking was not reinforced (extinction). Remember that the observer pigeon could not see the color of the model’s key. Thus, the only stimulus reliably correlated with reinforcement or its absence was the behavior of the model. Under these conditions, the observer learned when to peck to the key and when not to peck because the pecking would not be reinforced. Thus, the model’s pecking or its absence was the stimulus controlling the observer’s pecking.

The apparatus in this room was designed to present stimuli that, through their correlation with different circumstances of reinforcement, come to control operant behavior. Some of the devices are for presenting simple lights and sounds, but others, like teaching machines, present very complex verbal stimuli. These verbal stimuli come to control verbal responding in principle in much the same way that the simpler lights and sounds come to control lever pressing and key pecking of rats and pigeons, respectively. Step inside...

Room 4: Arranging Consequences

The critical feature in learning is the immediate delivery of a consequence following an appropriate response. (A consequence need not follow every response, but when these consequences occur they should do so immediately after the targeted response.) Over the years a sophisticated technology evolved for such delivery. In the case of laboratory research with animals, this has involved using electrical and electromechanical devices to deliver, most often, food or water precisely. This precision was in the form of both the amount delivered per reinforcement period and the immediacy with which it followed the response. Most research with animals involved automatic control, first by simple electromechanical programming circuitry and more recently by digital computers that record responses and arrange reinforcers according to a program created by the experimenter. As a result, the program can detect the response virtually immediately, determine whether the schedule calls for it to be reinforced and, if so, operate the reinforcement device.

One of the first steps in controlling the reinforcer is to ensure its consistency. With pigeons this is done by presenting access to mixed grain or food pellets for a fixed period of time, as is illustrated with the grain hoppers. The precision of a liquid reinforcer is controlled by presenting pre-measured amounts of the liquid with either a small dipper or by allowing a fixed amount to drain from a reservoir connected to a tube that can be pinched or released electromechanically. Another way of ensuring consistency is to deliver food pellets of a predetermined size through a feeder of the sorts shown in the section on delivery devices for rats.

Reinforcers are not limited to biological events like food and water, of course. Because reinforcers are defined functionally in behavior analysis, in principle almost anything can serve as a reinforcer. As a result, devices were developed to allow the experimenter to dispense a variety of different things as reinforcers, appropriate to the subject or participant and the circumstances of the experiment. These devices were described as universal reinforcer dispensers. Several are featured in this room of the virtual museum. Step inside...

Room 5: Responses

What is a response? Behavior analysts define responses both structurally (in terms of the form of the response) and functionally (the effect of the response). Sometimes these two definitions are complementary and sometimes they are quite different from one another.

Consider the lever press response of a rat. A lever press is defined as any downward force on the lever sufficient to operate an electric switch attached to it. Each separate switch operation constitutes one response. This is a structural or formal definition. Now, with this definition the only criterion for a “lever press response” is switch closure. The form or topography of the response doesn’t matter. The rat can activate the switch with its front paw or its back paw, or it can bite the lever with its mouth. The sole criterion for the response to have occurred is that the electric switch be operated. The response is defined in terms of a common effect on the environment. This constitutes a functional definition of the response. So, in this case the structural and functional definitions of the response are the same.

In everyday life, typing on a keyboard can be maintained by many different consequences. The consequences of typing can be to avoid missing a deadline or it can be to gain access to needed information. In this case the topography or form of the two responses is identical, but the consequences are different. In the first example the response is maintained because it avoids an aversive consequence and in the second example it is maintained because it results in a positive consequence. Are the two responses the same? Structurally, yes, but functionally no.

The devices displayed in this room all are attempts to establish precision in defining a response. This precision is achieved by defining the response electromechanically, usually by means of some type of electric switch operation. In many situations outside the laboratory, however, it is not possible to define the response in this way. Under such circumstances, it becomes necessary to achieve precision in measuring the response by having multiple human observers, well-trained in observing the response, watching for the response and recording its occurrence. Precision is achieved when there is a high level of agreement between the observers with respect to instances of occurrence, and nonoccurrence, of the target response. Step inside...