A bird's eye view of cognition

The Alex Studies: Cognitive and Communicative Abilities of Grey Parrotsby I.M. Pepperberg, Harvard University Press, 2000. £24.95 (434 pages) ISBN 0 674 00051 XChapter 1 of the Kama Sutra suggests that in order to live a healthy, aesthetically pleasing life, one should spend at least one hour every morning teaching parrots to speak. In contrast to most unrefined cognitive scientists, Irene Pepperberg has taken this maxim to heart. Since 1977, she and her colleagues at the University of Arizona have spent nearly ten hours a day teaching parrots – or more specifically, one African grey parrot, Alex – to speak. The culmination of her 23 years of aesthetic living is The Alex Studies: Cognitive and Communicative Abilities of Grey Parrots.The Alex Studies reads as a historical account of Pepperberg's work with Alex, beginning with the day that Alex was plucked at random from among his pet store cagemates to become part of scientific history. As we read in Chapter 2, Pepperberg attributes Alex's success not to a lucky choice on the part of the pet store staff, but to the use of a novel training paradigm which she calls the Model/Rival (M/R) technique. In this training paradigm, the subject watches as two human experimenters interact in a way that imitates the type of responses that the subject is meant to learn. Thus, one of the experimenters asks the other a question about an object (e.g. ‘what color?’). If the learner answers correctly, she is praised and receives the object as a reward. If she answers incorrectly or unclearly, the teacher removes the object and scolds her. In this way, the other experimenter serves both as the model for Alex's behavior and as his rival for the experimenter's attention. Alex, who wants access to the objects and the experimenters, soon gets in on the action, mimicking the labels used by the experimenter and the training begins. Once trained on new labels and concepts using the M/R technique, Alex is then tested in a series of novel generalization tasks.The chapters that follow demonstrate the success of the M/R technique and the remarkable degree of Alex's cognitive abilities. At present, Alex can produce and comprehend over 50 words, including words for colors, materials and shapes. He can make simple requests (e.g. ‘want cork’). He is able to count up to six. He passes standard tests of object permanence and understands relative concepts like same/different and bigger/smaller. Each chapter describes Alex's training and testing in painstaking detail and provides numerous examples that go beyond the statistics and give the reader a true sense of Alex's mastery of different tasks. Throughout, Pepperberg is careful to tackle alternative explanations and cautious about her interpretations of Alex's performance.Although Alex's capacities will undoubtedly impress even the most skeptical of readers, those well-versed in the cognitive sciences may be left somewhat dissatisfied with Pepperberg's discussion of Alex's accomplishments. For although she often compares Alex's performance to that of other animals, especially language-trained primates and marine mammals, she rarely applies Alex's performance to unanswered questions in the fields of human cognition and development. In Chapter 7, for example, Pepperberg examines whether Alex can understand and use numerical concepts. Although she ties his striking performance to the literature on subitizing abilities in animals, she fails to relate Alex's numerical abilities to the current debate about number representation in non-human animals and prelinguistic infants1.xBuilding a cognitive creature from a set of primitives: evolutionary and developmental insights. Hauser, M.D and Carey, S. : 51–106See all References, 2.xPsychological foundations of number: numerical competence in human infants. Wynn, K. Trends Cognit. Sci. 1998; 2: 296–303Abstract | Full Text | Full Text PDF | PubMed | Scopus (127)See all References. Similarly, Alex's impressive ability to learn words is all too rarely linked up with work on children's word learning. As we learn in Chapter 4, Alex seemed to master his first color terms quite easily, but human children struggle to learn their first color labels3xLearning color words involves learning a system of mappings. Sandhofer, C.M and Smith, L.B. Dev. Psychol. 1999; 35: 668–679Crossref | PubMedSee all References3. Why does Alex learn color words so easily? Does his representation of color concepts differ from those of young children? In short, although Pepperberg continuously gives the reader a great appreciation of Alex's striking performance, she rarely provides us with much insight into the representations underlying this performance.Pepperberg intends her work to be a ‘panoramic view of [the] data’ (p. ix),and it is certainly that and even more. Although her cautious intepretations may frustrate those cognitive scientists interested in her take on the nature of avian conceptual representations, The Alex Studies is a rich and well-organized summary of all the work with Alex to date and provides an indispensable reference for anyone interested in her research program.