Young infants' visual fixation patterns in addition and subtraction tasks support an object tracking account.

This is the final version of the article. Available from Elsevier via the DOI in this record.Investigating infants' numerical ability is crucial to identifying the developmental origins of numeracy. Wynn (1992) claimed that 5-month-old infants understand addition and subtraction as indicated by longer looking at outcomes that violate numerical operations (i.e., 1+1=1 and 2-1=2). However, Wynn's claim was contentious, with others suggesting that her results might reflect a familiarity preference for the initial array or that they could be explained in terms of object tracking. To cast light on this controversy, Wynn's conditions were replicated with conventional looking time supplemented with eye-tracker data. In the incorrect outcome of 2 in a subtraction event (2-1=2), infants looked selectively at the incorrectly present object, a finding that is not predicted by an initial array preference account or a symbolic numerical account but that is consistent with a perceptual object tracking account. It appears that young infants can track at least one object over occlusion, and this may form the precursor of numerical ability.This research was funded by a grant from the Nuffield Foundation (SGS/32130) to the first author, a grant from the Economic and Social Research Council (RES-000-22-1113 and ES/K000934/1) to the first author, and grants from the National Institutes of Health (HD-48733 and HD-40432) to the last author. We thank the infants and parents for contributing to the research

Young infants' visual fixation patterns in addition and subtraction tasks support an object tracking account

Investigating infants' numerical ability is crucial to identifying the developmental origins of numeracy. Wynn (1992) Nature, 358, 749-750, claimed that 5-month-old infants understand addition and subtraction as indicated by longer looking at outcomes that violate numerical operations (i.e., 1 + 1 = 1, or 2 – 1 = 2). However, her claim is contentious, with others suggesting that her results might reflect a familiarity preference for the initial array, or that they could be explained in terms of object tracking. To cast light on this controversy, Wynn’s conditions were replicated with conventional looking time supplemented with eye tracker data. In the incorrect outcome of 2 in a subtraction event (2 – 1 = 2) infants looked selectively at the incorrectly present object, a finding that is not predicted by an initial array preference account or a symbolic numerical account, but which is consistent with a perceptual object tracking account. It appears that young infants can track at least one object over occlusion, and this may form the precursor of numerical ability

Capuchin monkeys individuate objects based on spatio-temporal and property/kind information : evidence from looking and reaching measures

This paper is an output of the project ‘Rethinking Mind and Meaning: A case study from a co-disciplinary approach’ (Award Nr.: AH/ L015234/1), funded by the Arts and Humanities Research Council (AHRC), as part of the Science in Culture Theme (http://www.sciculture.ac.uk).A core component of any folk physical understanding of the world is object individuation - the cognitive ability to parse sensory input into discrete objects. Whereas younger human infants use spatio-temporal information to individuate objects, they do not use property and kind information until one year of age. Some researchers propose that object individuation based on property/kind information depends on language acquisition and sortal concepts. However, there is evidence that preverbal infants and nonhuman animals also use both types of information. The present study aimed to further explore the evolutionary origins of object individuation by testing a new-world monkey species, capuchin monkeys (Sapajus spp.), using both manual search (n = 29) and looking time (n = 23) measures. In Spatio-temporal trials, subjects saw one or two objects dropped into a box, but always found (or saw) only one. In Property/kind trials, subjects saw either object A or B being dropped into a box and then always found (or saw) object A. The capuchin monkeys looked longer and searched more on inconsistent trials – with outcome differing in quantity or in kind - which suggested that they had expectations based on both spatio-temporal and property-kind representations. Looking time and search measures gave convergent results at the group but not at the individual level. Our results add to the existing evidence contradicting the linguistic hypothesis of property/kind individuation. However, contrary to recent discussions, we argue that these and related results can be explained without appealing to the notion of sortal concepts or multiple representational systems, and suggest that a full picture of the ontogeny and phylogeny of object individuation requires further empirical and theoretical research.Publisher PDFPeer reviewe

Mapping the Visual Icon

It is often claimed that pre-attentive vision has an ‘iconic’ format. This is seen to explain pre-attentive vision’s characteristically high processing capacity and to make sense of an overlap in the mechanisms of early vision and mental imagery. But what does the iconicity of pre-attentive vision amount to? This paper considers two prominent ways of characterising pre-attentive visual icons and argues that neither is adequate: one approach renders the claim ‘pre-attentive vision is iconic’ empirically false while the other obscures its ability to do the explanatory work which motivates positing pre-attentive visual icons in the first place. With this noted, I introduce the (heretofore unarticulated) notion of an ‘Analog Map’ and argue that it provides a superior characterisation of pre-attentive vision’s iconicity. I then argue that this forces a reassessment of debates which have traditionally presupposed the iconicity of pre-attentive vision, emphasising ramifications for the viability of a format-based perception-thought border

Where concepts come from: a theory of concept acquisition

How do people acquire new concepts? Most theorists (including Quine, Chomsky, Fodor, and many others) assume that childhood learning is a kind of theory-building. This picture implies that children acquire new concepts by deploying concepts they already possess, and that in turn implies what I call the Conceptual Mediation Thesis (CMT): that, in order to acquire any new concepts, a cognizer must first already have some concepts. I argue that CMT is false. While CMT implies that at least some concepts are innate, it is widely accepted because it is thought to provide the only way to explain how concepts are acquired. However, I argue that the apparent explanatory virtues of CMT are in fact illusory. I then show how we can satisfy the explanatory goals that CMT was supposed to satisfy without postulating any innate concepts – indeed without any innate mental representations at all. I distinguish between indicating states and representing states of cognizers. Indicating states differ from representing states in being stimulus-bound: only those tokens directly caused by what they indicate count as correct. I argue that perception produces states that indicate features of the environment. These indicating states serve as input to mechanisms that record these states. These recording devices, in turn, respond to the input of systematically similar indicating states by creating states that represent what those indicating states merely indicate. I describe some processes whereby these recording devices can create representational states without any representational input. I argue that this explanation requires no appeal to mental representations that the agent already possessed. Finally, I show that this approach to concept acquisition has the resources to explain a variety of psychological phenomena that traditional views struggle to accomodate

Perceptual object tracking

This paper presents an improved kernel-based target tracking that uses new and effective features able to describe the target appearance. The key idea consists of adopting features that are related to the visual perception of the target in place of its color histogram. The change of the feature space is twofold advantageous. It allows us to faithfully follow the target and to considerably reduce the computational cost of the whole tracking algorithm thanks to the reduced dimension of the perceptual feature space. Preliminary tests on some video sequences are encouraging. The proposed tracker is able to follow the target even in case of complete occlusion for some consecutive frames. Moreover, it is more stable than the algorithm that uses just the luminance histogram as target feature. Finally, it is robust to the presence of other moving targets. © 2012 IEEE