Behavior Research Methods, Instruments, & Computers 1994, 26 (2), 134-14/ Sniffy, the virtual rat: Simulated operant conditioning JEFF GRAHAM, TOM ALLOWAY, and LESTER KRAMES Erindale College, University of Toronto, Mississauga, Ontario, Canada We report on the use of our Sniffy program to teach operant conditioning to 900 introductory psychology students. The simulation is designed primarily to teach the principles of shaping and partial reinforcement in an operant chamber. Advanced features are provided for exploring mod- eling issues and the learning parameters of the model. Students observe the rat's pretraining behaviors, shape barpressing, and explore the effects of partial reinforcement schedules on a cu- mulative record. Any of 30 actions can be trained to occur in specific locations in the Skinner box. This paper summarizes details about the software, interface, and instructional objectives. The Sniffy program is designed primarily to teach the principles of shaping and partial reinforcement in oper- ant conditioning. Advanced features are provided for the exploration of modeling issues and the learning parame- ters of the model. This program simulates many of the behaviors one would observe in a real rat learning to oper- ate in the controlled environment of an operant chamber. Sniffy, a simulated rat, can be trained to perform any of the 30 behaviors in its repertoire by pairing food deliv- ery with the target behavior. So that students may fully appreciate the major features of operant conditioning, we have provided instructions for two 2-h lab sessions. The first allows students to train Sniffy to press the bar for food, and the second explores the changes in behavior that occur under partial reinforcement (PRF) conditions. Spontaneous recovery, discrimination, and chaining are phenomema that have not yet been implemented in our program. We do not claim that the exact slope of the re- sponse rates observed in real rats have been replicated, although we have attempted to display the typical differ- ences observed among the four major PRF schedules. Careful instructors may refer to Sniffy as rattus silico- nus and treat the learning objective as one in which the behavior of this new species needs to documented, veri- fied, and tested. In the following sections, we present a rationale for the development of this simulation, a brief review of operant conditioning, and a summary of the two labs that we have run to date. Some of the background material is adapted from the program's extensive documentation. The final section provides a general description of the program and of how its major features are implemented. We gratefully thank Erindale College, the University of Toronto Com- puter Shop, and Apple Canada for the support that made our teaching lab possible. Greg Wilson is the mastermind behind Sniffy's behavior, and we thank him for making the achievement of an improbable task a reality. Correspondence should be addressed to J. Graham, Psychol- ogy Department, Erindale College, University of Toronto, 3359 Mis- sissauga Rd., Mississauga, ON, Canada L5L IC6. Ethics and Economics The ideal way to learn about operant conditioning would be to work with a real rat in a real operant chamber. How- ever, financial and ethical constraints make this imprac- tical in most university and college settings. An operant chamber capable of delivering food reinforcement, along with a computer to control events in the chamber, record the animal's barpresses, and produce printable records would cost from $2,000 to $3,000 per student work station. Purchasing and maintaining rats is also expensive. A young adult rat suitable for training in an operant cham- ber costs about $10 from a commercial distributor. In both the U.S. and Canada, animal-care regulations specify that all laboratory animals must be housed under specified con- ditions, that they must be kept in specially designed fa- cilities, and that they must be cared for by specially trained animal-care technicians. Typical animal care costs $10 per rat per month. Most universities and colleges do not have facilities to house large numbers of animals used for teaching, and even if they did have enough room, the cost would be great. Thus, in recent years, few undergraduate students have been able to get hands-on experience with operant conditioning, even though operant conditioning is one of the most important topics covered in under- graduate psychology courses. Overcoming these finan- cial barriers is one of the main reasons we created Sniffy. Other considerations are ethical. Whether or not one is ever ethically justified to use animals in scientific re- search has become a hotly debated topic in recent years. Some argue that the use of laboratory animals is always unethical, but more would probably agree that the use of research animals is justified if the animals are well treated and if the research is likely to produce substantial new scientific knowledge. The use of animals for teaching purposes-where no new scientific knowledge will be gained-is harder to justify. However, experiments on operant conditioning of the type that Sniffy simulates would cause no pain whatsoever and would produce lit- tle, if any, physical discomfort to a live animal. Copyright 1994 Psychonomic Society, Inc. 134