Primates in cyberspace: using interactive computer tasks to study perception and action in nonhuman animals.

In the scientific enterprise, to a larger extent than we mightlike to think, our measurement instruments define the ques-tions we can ask. Centuries ago, the telescope and the mi-croscope opened new universes for human inspection. Morerecently, particle accelerators enabled physicists to explorethe structure of the atom. Today neuroimaging techniquessuch as FMRI (functional magnetic resonance imaging)have altered the questions that we can ask about neuro-logical functioning. In experimental studies of behavior innonhuman animals, numerous apparatus developed by in-genious investigators over the past century (e.g., Thorndike,Yerkes, Kluver, Tinklepaugh, Tolman, Crawford, Hayesand many others) provided new ways to study animal “in-telligence” and learning. We are currently in the midst ofanother wave of technological innovation in which ex-panding use of digital technology is the agent of change.This wave of innovation will open new vistas in behavioralstudies as surely as neuroimaging has done for neuro-science.The computer has dramatically widened our methodsof investigating comparative cognition in nonhuman spe-cies. Prior to the appearance of the desk-top computer,Skinner and others adapted mechanical and electronicrecording and dispensing mechanisms to automate inter-trial timing, delivery of reinforcers and data recording inexperiments with rats and pigeons. The first contributionof computers to comparative cognitive research was pri-marily to automate even further the functions previouslyhandled by electronic timers and counters. The devices alsoserved as a storage mechanism for our expanding data setsand enabled us to conduct more detailed analyses of ourdata sets. In addition to these assistive uses, investigatorsincreasingly exploited computerized systems to presentexperimental problems to subjects that otherwise wouldhave been presented by using other forms of two- or three-dimensional (2D or 3D) displays. In most testing situations,the computer now serves as a means of presenting a displayand registers the subject’s response (a choice; a latency).In this case, the subject acts on the basis of the display, butit does not interact with the system itself; the subject doesnot “use” the system. Although quite practical, none ofthese uses of the emerging technology actually changed thequestions experimenters addressed in their studies.As the behavioral research community’s familiarity and“comfort” with computers has increased, we are startingto use computers in a broader way in our research. We viewthe emergence of interactive paradigms in computerizedresearch protocols as the next wave of methodological in-novation in animal cognition. This work was pioneeredwith nonhuman primates by the research teams of DuaneRumbaugh (Richardson et al. 1990; Rumbaugh et al. 1991)and Tetsuro Matsuzawa (Tomonaga and Matsuzawa 1992;Iverson and Matsuzawa 1996, 2001; Kawai and Matsuzawa2001). In essence, in these paradigms, the nonhuman sub-jects have become system “users.”To appreciate how this different perspective allows usto ask new questions, consider the burgeoning literatureusing “virtual reality” in humans to study topics such asoptical flow and path integration (Kearns et al. 2002), nav-igation and steering behavior (Fajen, 2001), spatial updat-ing (Wang et al. 2002), and change blindness (the inabil-ity to notice scene changes) (Triesch et al. 2002). We takeit for granted that humans can act in virtual spaces, and(perhaps gratuitously) we assume that actions in virtual(2D) environments inform us about actions in physical(3D) environments. We are just beginning to study nonhu-man primates as “users” or actors in virtual reality situa-tions (see Washburn and Astur 2003).Investigators working with birds, and coming from adifferent theoretical and methodological community, havebegun to explore visual perception in the virtual environ-ment. One example of such work is the discrimination oftypes of object motion (Cook et al. 2001). These investi-gators questioned whether pigeons could discriminate be-tween optical flow fields simulating an object movingthrough versus around an object. The pigeons were able to