Abstract not found

In 1951, Lashley highlighted the importance of serial order for the brain and behavioural sciences. He considered the response chaining account untenable and proposed an alternative employing parallel response activation and "schemata for action". Subsequently, much has been learned about sequential behaviour, particularly in the linguistic domain. We argue that these developments support Lashley's picture, and recent computational models compatible with it are described. The models are developed in a series of steps, beginning with the basic problem of parallel response competition and its possible resolution into serial action. At each stage, important limitations of the previous models are identified and simple additions proposed to overcome them, including the provision of learning mechanisms. Each type of model is compared with relevant data, and the importance of error data is emphasized. Taken together, the models constitute a unified approach to serial order which has achieved considerable explanatory success across disparate domains.

This thesis aims to develop a psychologically plausible account of concepts by integrating key insights from philosophy (on the metaphysical basis for concept possession) and psychology (on the mechanisms underlying concept acquisition). I adopt an approach known as informational atomism, developed by Jerry Fodor. Informational atomism is the conjunction of two theses: (i) informational semantics, according to which conceptual content is constituted exhaustively by nomological mind–world relations; and (ii) conceptual atomism, according to which (lexical) concepts have no internal structure. I argue that informational semantics needs to be supplemented by allowing content-constitutive rules of inference (“meaning postulates”). This is because the content of one important class of concepts, the logical terms, is not plausibly informational. And since, it is argued, no principled distinction can be drawn between logical concepts and the rest, the problem that this raises is a general one.

This paper describes a research program designed to use agent models to understand how primates incorporate new, learned behavior safely into their established, reliable behavior repertoires. We suggest that some of the findings in the primate learning literature that we currently find surprising may in fact reflect evolved solutions to the problem of safe learning in intelligent agents. We sketch an approach to trying to model this learning, with the expectation that our experience will also lead to insights into idioms and strategies for incorporating safe learning into artificial agents.

To what extent is linguistic structure learnable from statistical information in the input? One set of cues which might assist in the discovery of hierarchical phrase structure given serially presented input are the dependencies, or predictive relationships, present within phrases. In order to determine whether adult learners can use this statistical information, subjects were exposed to artificial languages which either contained or violated the kinds of dependencies which characterize natural languages. The results suggest that adults possess learning mechanisms which detect and utilize statistical cues to phrase and hierarchical structure. A second experiment contrasted the acquisition of these linguistic systems with the same grammars implemented as non-linguistic input (sequences of non-linguistic sounds or shapes). These findings suggest that constraints on the mechanisms which highlight the statistical cues which are most characteristic of human languages are not specifically tailored for language learning.

To survive, organisms must be able to identify edible objects. However, we know relatively little about how humans and other species distinguish food items from non-food items. We tested the abilities of semi-free-ranging rhesus monkeys (Macaca mulatta) to learn rapidly that a novel object was edible, and to generalize their learning to other objects, in a spontaneous choice task. Adult monkeys watched as a human experimenter first pretended to eat one of two novel objects and then placed replicas of the objects at widely separated locations. Monkeys selectively approached the object that the experimenter had previously eaten, exhibiting a rapidly induced preference for the apparently edible object. In further experiments in which the same objects were used as tools or were manipulated at the face but not eaten, we fail to observe an approach bias, providing evidence that the monkeys' pattern of approach in the earlier experiments was specific to objects that were eaten. Subsequent experiments tested how monkeys generalized their preference for an edible object by first allowing them to watch a human experimenter eat one of two objects and then presenting them with new objects composed of the same substance but differing from the original, edible object in shape or color. Monkeys ignored changes in the shape of the object and generalized from one edible object to another on the basis of color in conjunction with other substance properties. Finally, we extended this work to infant rhesus monkeys and found that, like adults, they too used color to generalize to novel food objects. In contrast to adults, however, infants extended this pattern of generalization to objects that were acted on in other ways. These results suggest that infant monkeys form broader object categor...

One of the longstanding issues in language research has been the extent to which the mechanisms underlying language acquisition are uniquely human. The primary goal of this article is to introduce the reader to some of the recent developments in comparative language research that have shed new light on this issue. To appreciate the significance of the new developments, we begin with a brief historical overview of language studies that have adopted a comparative approach, and then discuss a subset of the relevant theoretical accounts that seek to explain why humans are the only species capable of acquiring language. We next focus on findings from behavioral studies comparing the performance of human infants and adults with nonhuman primates on tests that tap the perceptual and learning mechanisms that are fundamental to language acquisition. We argue that in cases where the behavioral data appear similar across populations, there is a need to investigate the underlying computational abilities and units of analysis to correctly specify the degree to which the mechanisms are truly shared or are uniquely specified. Dogbert: I once read that given infinite time, a thousand monkeys with typewriters would eventually write the complete works of Shakespeare.