University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications, Department of Psychology Psychology, Department of 11-2010 The challenges of understanding animal minds Jeffrey R. Stevens University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/psychfacpub Part of the Psychiatry and Psychology Commons Stevens, Jeffrey R., "The challenges of understanding animal minds" (2010). Faculty Publications, Department of Psychology. 512. https://digitalcommons.unl.edu/psychfacpub/512 This Article is brought to you for free and open access by the Psychology, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications, Department of Psychology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. SPECIALTY GRAND CHALLENGE ARTICLE published: 19 November 2010 doi: 10.3389/fpsyg.2010.00203 The challenges of understanding animal minds Jeffrey R. Stevens* Center for Adaptive Behavior and Cognition, Max Planck Institute for Human Development, Berlin, Germany *Correspondence: [email protected], [email protected] Comparative psychology is by nature an • Can animals use referential benchmark for parsimonious explanations. interdisciplinary science that lies at the communication? If a simpler, learning account can explain crossroads of psychology and biology but • How do animals track time and the data, then we should not invoke a more also draws from other fields in the natural, number? complex explanation. This stringent bench- social, and cognitive sciences. The study of • Do animals maintain a cognitive map mark has set a high bar for researchers in the the psychology of animals has been labeled of their environment? cognitive tradition to reject simple learning animal cognition, comparative cognition, • Do animals attend to the well being of explanations. Occasionally, the bar is raised animal learning, animal psychology, and others? higher and higher, sometimes to the extent animal intelligence. Here, comparative • How do animals categorize objects in that the learning mechanism becomes quite psychology is used interchangeably with their world? complex. How complex does a parsimoni- these terms, encompassing all fields that • Which emotional and motivational fac- ous explanation need to be before we accept explore the psychological mechanisms tors underly animal behavior? a representational one? How do we define underlying animal behavior, including the complexity of a mechanism? One solu- human behavior. Studying the psychology of other species tion is to sidestep the parsimony/complexity The primary goal of comparative psy- is not easy. With rare exceptions, we can- question completely. Rather than resorting chology is to understand the cognitive, not ask directly about their psychological to a scale of psychological complexity, we emotional, and motivational processes of states. Instead, we must make inferences can develop and test more precise models the animal mind. How do other animals about the psychology of animals based on of the phenomena of interest. perceive, learn about, and make decisions their behavior. Inferring internal mecha- Even after excluding simpler explana- in their worlds? From our pets to exotic nisms from external behavior results in a tions for phenomena, the question arises, animals portrayed in nature documenta- number of challenges for comparative psy- under what circumstances do animals ries, we are inherently curious about other chologists. Though we have met a number use the more complex form of cognition? animals. Comparative psychology both pro- of these challenges, several remain, slow- Possessing a particular psychological ability vides a window into their minds, as well as ing our progress in advancing comparative does not imply using it at every opportu- offers a unique perspective on the human psychology. To push forward, we must meet nity. In many cases, animals may use simpler mind. Which aspects of our psychology do these conceptual and practical challenges mechanisms, reserving the more complex animals share? Human uniqueness is con- head on. mechanisms for situations in which the sim- stantly challenged as we learn more about pler mechanisms do not work. The circum- the psychology of animal minds. Once dis- THE COMPLEXITY OF PARSIMONY stances under which animals use different tinctive human abilities – such as tool use, The difficulties of making inferences about mechanisms remains an open question in language, and mental time travel – appear, internal mechanisms has spawned two comparative psychology. at least to a degree, in other species. Though general approaches to studying cognitive other species exhibit elements of these abili- aspects of animal behavior. The animal INDIVIDUAL DIFFERENCES ties, the central question for comparing learning approach emphasizes the general A hallmark of data in comparative psychol- humans and animals remains, do humans learning principles, such as instrumental, ogy is variation across individuals. Despite and other animals share the same psycho- and Pavlovian conditioning, espoused by this, we have very little understanding of logical mechanisms? Hull, Spence, Tolman, and Skinner. The the sources of variation in psychological Comparative psychology explores many cognitive approach examines other forms mechanisms. Evolutionary models predict of the same topics as human psychology. of cognition such as perception, attention, individual differences in behavior (Wolf From learning and memory to commu- memory, categorization, navigation, timing, et al., 2007), but few models explore why nication and decision making, the field number, communication, decision mak- cognition and emotion should vary across investigates a number of key questions, for ing, and social cognition. Though learning individuals. A number of questions arise example: mechanisms often are considered simpler when developing a theoretical understand- explanations, some cognitive mechanisms ing of individual differences. Is there really • How do animals understand causal are more complex, requiring an organism variation in animal psychological abilities relationships in their environments? to generate a mental representation. Since or only in the expression of these abilities? • Can animals represent the perceptions, Morgan’s (1903) admonition to opt for the To what extent is this variation adaptive? To intentions, and beliefs of others? most parsimonious explanation supported what extent does the variation result from • Do animals plan for the future? by the data, the learning tradition has set the environmental influences? Are there general www.frontiersin.org November 2010 | Volume 1 | Article 203 | 1 Stevens Understanding animal minds reasons for variation in psychology or do share similar psychological mechanisms? that tap natural behaviors and situations we need to consider each ability separately? What kinds of evolutionary pressures can yield more valid studies of compara- Researchers of animal behavior investigate shape psychological mechanisms across tive psychology. individual differences under the headings of species? Does the social environment play animal personality, behavioral syndromes, a special role in shaping psychology? How STRONG INFERENCE and temperament. We must now extend this can we test whether species share actual Much of comparative psychology is based study of variation at the psychological level mechanisms rather than just general psy- on existence proofs: Do animals have theory and explore the sources of such variation. chological abilities? Comparisons across of mind, metacognition, episodic memory, species pose difficulties and require great empathy, or other-regarding preferences? To PUttING THE COMPARATIVE BACK care regarding the species tested and the further mature, however, the field needs to INTO COMPARATIVE PSYCHOLOGY experimental methods used. Nevertheless, develop more sophisticated models of how Despite the name and origins of the field, the fruits of this labor will yield valu- psychological mechanisms work, not just comparative psychology lacked many com- able insights into the nature of animal whether they are present and what influ- parative studies during much of the twenti- psychology. ences them. Weisman (2008) offers an eth century. Only a handful of species acted important challenge to the young research- as the workhorses of the field: the pigeon, ECOLOGICAL RELEVANCE ers in behavioral and cognitive science: the rat, and the rhesus macaque. Focusing Simon (1990) argued that a serious study embrace Platt’s (1964) notion of strong on a few species offers a more in-depth and of cognition must explore both the mind inference. Strong inference emphasizes the cumulative method for understanding the and the environment in which the mind development of multiple hypotheses and psychology of those species. This restric- interacts. He likened this to two blades the design of critical experiments allowing tion, however, limits our broader under- in a pair of scissors that cannot function for alternative outcomes that will exclude standing of psychological mechanisms in unless both blades are present. This pro- some of the hypotheses. Currently, many animals. Comparative psychologists have vides an important lesson for comparative behavioral scientists rely on testing a single lamented this lack of diversity for decades psychology as well. Studies