Do children draw upon abstract representations of number when they perform approximate arithmetic operations? In this study, kindergarten children viewed animations suggesting addition of a sequence of sounds to an array of dots, and they compared the sum to a second dot array that differed from the sum by 1 of 3 ratios. Children performed this task successfully with all the signatures of adults ’ nonsymbolic number representations: accuracy modulated by the ratio of the sum and the comparison quantity, equal performance for within- and cross-modality tasks and for addition and comparison tasks, and performance superior to that of a matched subtraction task. The findings provide clear evidence for nonsymbolic numerical operations on abstract numerical quantities in children who have not yet been taught formal arithmetic.

Abstract not found

This thesis attempts to understand infant behaviour by designing autonomous software agents to reproduce those behaviours in simulation. The infant behaviours that have been investigated are related to the phenomenon of infant attachment. Empirical studies of infant behaviour are abstracted and the function of the behaviours are assessed from an evolutionary perspective. The behaviours are then reformed as scenarios against which simulations can be evaluated. These studies include naturalistic observation of infants at home and exploring a park, and undergoing the Strange Situation Experiment. A number of information processing architectures have been constructed that reproduce the infant behaviours described in scenarios. These vary in complexity from a reactive architecture with no capacity to learn, to reactive architectures that can learn by reinforcement, and deliberative architectures that can reason by forming simple plans. Computational experiments undertaken with interacting infant and carer agents show the presence of interesting dynamic properties, such as positive feedback loops. These feedback loops may provide an explanation for the empirical finding that patterns of infant attachment response cluster into three categories. This thesis demonstrates how the methodology that it is uses in investigating attachment behaviour in infancy may be extended to many other infant and developmental behaviours.

under the supervision of Prof Dr Michiel van Lambalgen, and submitted

A Grey parrot (Psittacus erithacus) that was able to quantify 6 item sets (including subsets of heterogeneous groups, e.g., blue blocks within groupings of blue and green blocks and balls) using English labels (I. M. Pepperberg, 1994a) was tested on comprehension of these labels, which is crucial for numerical competence (K. C. Fuson, 1988). He was, without training, asked “What color/object [number]?” for collections of various simultaneously presented quantities (e.g., subsets of 4, 5, and 6 blocks of 3 different colors; subsets of 2, 4, and 6 keys, corks, and sticks). Accuracy was greater than 80% and was unaffected by array quantity, mass, or contour. His results demonstrated numerical comprehension competence comparable to that of chimpanzees and very young children. He also demonstrated knowledge of absence of quantity, using “none” to designate zero.

ABSTRACT—In a study exploring the origins of cognitive dissonance, preschoolers and capuchins were given a choice between two equally preferred alternatives (two different stickers and two differently colored M&M’s s, respectively). On the basis of previous research with adults, this choice was thought to cause dissonance because it conflicted with subjects ’ belief that the two options were equally valuable. We therefore expected subjects to change their attitude toward the unchosen alternative, deeming it less valuable. We then presented subjects with a choice between the unchosen option and an option that was originally as attractive as both options in the first choice. Both groups preferred the novel over the unchosen option in this experimental condition, but not in a control condition in which they did not take part in the first decision. These results provide the first evidence of decision rationalization in children and nonhuman primates. They suggest that the mechanisms underlying cognitive-dissonance reduction in human adults may have originated both developmentally and evolutionarily earlier than previously thought. Cognitive dissonance is one of the most heavily studied phenomena in the history of psychology. The term cognitive dissonance describes a psychological state in which an individual’s cognitions—beliefs, attitudes, and behaviors—are at odds (Festinger, 1957). People experience cognitive dissonance as aversive (Elliot & Devine, 1994), and are motivated to resolve the inconsistency between their discrepant cognitions. Psychologists have long been interested in the nature of cognitive dissonance, as this phenomenon has implications for many areas Address correspondence to Louisa Egan, Department of Psychology,

Humans are unique among animals for both the diverse complexity of our cognition and our reliance on culture, the socially-transmitted representations and practices that shape experience and behavior. Adopting an evolutionary psychological approach, in this essay we consider four different facets of the relationship between cognition and culture. We begin with a discussion of two well-established research traditions, the investigation of features of mind that are universal despite cultural diversity, and the examination of features of mind that vary across cultures. We then turn to two topics that have only recently begun to receive attention, the cognitive mechanisms that underlie the acquisition of cultural information, and the effects of features of cognition on culture. Throughout, our goal is not to provide comprehensive reviews so much as to frame these issues in such a way as to spur further research.