Behavior Research Methods, instruments, and Computers 1993, 25 (2), 257-2 71 10. REAL-TIME DATA COLLECTION Chaired by William Maki, North Dakota State University PsyScope: An interactive graphic system for designing and controlling experiments in the psychology laboratory using Macintosh computers JONATHAN COHEN, BRIAN MAcWHINNEY, MATI’HEW FLATF, and JEFFERSON PROVOST Carnegie Mellon University, Pittsburgh, Pennsylvania PsyScope is an integrated environment for designing and running psychology experiments on Macintosh computers. The primary goal of PsyScope is to give both psychology students and trained researchers a tool that allows them to design experiments without the need for programming. PsyScope relies on the interactive graphic environment provided by Macintosh computers to ac- complish this goal. The standard components of a psychology experiment—groups, blocks, trials, and factors—are all represented graphically, and experiments are constructed by working with these elements in interactive windows and dialogs. In this article, we describe the overall or- ganization of the program, provide an example of how a simple experiment can be constructed within its graphic environment, and discuss some of its technical features (such as its under- lying scripting language, timing characteristics, etc.). PsyScope is available for noncommercial purposes free of charge and unsupported to the general research community. Information about how to obtain the program and its documentation is provided. The laboratory microcomputer has become a crucial tool for conducting psychology experiments. In recent years, a number of software programs have been devel- oped on the Macintosh that rely on its user-friendly graphic interface to assist in the implementation of psy- chology experiments on microcomputers. However, for the most part, these have been limited in range and/or power. For example, all of them lack a programming, or scripting, language, and few of them have the capabil- ity to add external devices for more accurate timing of PsyScope was conceived and designed by Jonathan Cohen and Brian MacWhinney and implemented by Matthew Flatt and Jefferson Provost. Contributions to its development were also made by Jay Gowdy, Eric Sedlar, Darius Clynes, Eric Selberg, and Robert Findler. Support for its development was provided by NIMH grants (MH 00673 and MH 47073) to the first author, an NIH grant (RD 17790) to the second author, and a FIPSE grant (P1 16B2) to both the first and second authors. In addition, support was provided by the laboratories of Elizabeth Bates, Maggie Bruck, Cathy Harris, Mark Johnson, Jay McClelland, Mark Seidenberg, and Jonathan Vaughan, who together have formed the PsyScope Development Consortium. Correspondence should be ad- dressed via electronic mail to either Jonathan Cohen (jc5e + @andrew. cmu.edu) or Brian MacWhinney (brian+@andrew. cmu.edu) or via U.S. mail to either author at the Department of Psychology, Carnegie Mel- lon University, Pittsburgh, PA 15213. input and stimuli. There are powerful systems that run on other platforms. For example, Walter Schneider at the University of Pittsburgh has developed the most sophisti- cated of these—a system called the Microcomputer Ex- perimental Laboratory (MEL; Schneider, 1988). However, this runs only on IBM-compatible PCs and lacks the ad- vantages of an easy-to-use graphic interface. Vaughan (1992) has articulated the call for the development of an easy-to-use, intuitive environment in which psychologists— neophytes and experts alike—can develop experiments without the need for sophisticated programming skills. We have developed a program called PsyScope that is intended to address many of these limitations. PsyScope was developed at Carnegie Mellon University by Jona- than Cohen, Brian MacWhinney, Matthew Flatt, and Jefferson Provost. The primary goals of PsyScope are to eliminate the need for programming skills on the part of users and to provide them with a set of tools that cor- responds directly to the conceptual building blocks of ex- perimental design: groups, blocks, trials, events (stimuli and responses), and factors. The program runs on Macin- tosh computers and provides a graphic interface that al- lows the user to design an experiment starting with the scientific question in mind, rather than being distracted 257 Copyright 1993 Psychonomic Society, Inc.