Central Issues in the Comparative Study of Cognition
Edward Wasserman earned his B.A. at UCLA and his Ph.D at Indiana University. He is now Stuit Professor of Experimental Psychology at the University of Iowa. Thomas R. Zentall earned his B.S. degree in psychology, his B.E.E in Electrical Engineering from Union College in 1963, and his Ph.D. from the University of California at Berkeley in 1969. He is now a Professor of Psychology at the University of Kentucky. Together they wrote Comparative Cognition: Experimental Explorations of Animal Intelligence. Below is an excerpt which looks at one reason why this research is so difficult.
Definitional and Observational Concerns
Few things set the animal world so dramatically apart from the rest of nature as does cognition–an animal’s ability to remember the past, to choose in the present, and to plan for the future. To the best of our knowledge, the human and nonhuman animals on our planet are the only living beings that evidence cognition. (The continually controversial case of cognition and the inanimate digital computer will not concern us here; see Blakemore & Greenfield, 1987, for a discussion of this issue.)
Despite the remarkable capacity, intricacy, and flexibility of adaptive behavior, cognition is not a magical or supernatural power; it is the natural product of the biological activity of the brain…Elucidating the workings of the brain is undoubtedly one of the most daunting challenges ever undertaken by the human species. The current excitement that is being generated by discoveries in the field of neuroscience testifies to the importance of this matter.
Unlike the operation of other bodily systems (like respiration), whose activity is usually directly observed in the isolated responses of particular organs (like the lungs), cognition is usually indirectly evidenced through the diverse responses of many different effectors, generally the skeletal muscles (although emerging methods in neuroscience herald the advent of more direct measures of brain activity). Hence, a youngster may sing, hum, or whistle a tune; play it on a piano, xylophone, or trumpet; tap out its rhythm with a stick on a drum; or write out its score with a pen on a sheet of paper. All of these various behaviors divulge her musical knowledge… Therefore, although the core of cognition lies in the activity of the brain, we usually learn of cognition via the early comparative psychologist Romanes (1883/1977) dubbed “behavioral ambassadors” (Wasserman, 1984).
Unequivocal distinctions between cognition and simpler Pavlovian and instrumental learning processes, as well as other behavioral or physiological processes like reflex action, maturation, fatigue and motivation, are devilishly difficult to devise. There is often spirited disagreement among researchers on the merits of these distinctions, as when workers try to explain the occurrence and integration of elaborate behavior patterns like courtship rituals.
Many cognitive processes may be behaviorally indistinguishable from simpler learning processes. For example, one may learn and remember a telephone number, say 987-2468, by repeatedly saying the number aloud (i.e., learning by rote), considered by many theorists to represent a simple learning process. Alternatively, one may notice that the telephone number contains digit patters like the descending serial order 9-8-7 and the even-number sequence 2-4-6-8, a cognitive process. Unless clear evidence is provided that a more complex cognitive process has been used, C. Lloyd Morgan’s famous canon of parsimony obliges us to assume that is had not; we must then conclude that a simpler learning process can account for learning.
The challenge then is to identify flexible behavior that cannot be accounted for by simpler learning mechanisms. Thus, a cognitive process is one that does not merely result from the repetition of a behavior or from the repeated pairing of a stimulus with reinforcement. Cognitive processes often involve emergent (untrained) relations. Furthermore, because simple learning is assumed to generalize to physically similar stimuli or contexts, in order to qualify as a cognitive process, the emergent relations cannot involve stimuli or relations that are physically similar to those that were explicitly trained.
For example, if one wanted to show that pigeon had the concept of identity, then one might train a pigeon to match red and green hues (i.e., to select red rather than green when the initial stimulus is red, but to select green rather than red when the initial stimulus is green). If one later tested the pigeon with orange and teal stimuli and one found good transfer, then one could assume that the concept of identity had been demonstrated because orange is similar to red and teal is similar to green. On the other hand, if one tested the pigeons with stimuli (e.g., black-and-white shapes such as circle and square), then evidence of good transfer might suggest that an untrained relation had emerged (i.e., that hte concept of identity had been demonstrated…). Thus, the demonstration of cognitive behavior implies that simpler learning processes cannot account for the demonstrated actions.