Symposium
Chair: Rick O. Gilmore
Discussant: Martha E. Arterberry
Characterizing the nature of spatial perception early in life andunderstanding its development are issues of central interest andlongstanding concern to developmentalists. The presentations in thissymposium aim to answer three fundamental questions about spatialperception and cognition in early infancy: What is the nature of younginfants' spatial representations? How do these representations change?Why do they change?The presentations in this symposium will bring together researchers whosework focuses on these questions from a variety of theoretical perspectives,uses a diverse set of techniques, and examines spatial processing inmultiple perception and action domains. For example, one presentation willfocus on the development non-metric, categorical spatial representations.Another will discuss how biological and experiential factors jointlycontribute to the development of body-centered representations of visualdirection. A third presentation will discuss the development ofsensitivity to multimodal, auditory and visual, sources information whichspecify a variety of spatial and object properties. The final presentationwill present a new perspective on the widely accepted transition fromegocentric to allocentric representations. Together, the presentations willsuggest that there are multiple forms of spatial information which guideyoung infants' behavior, that the spatial information which guides behaviorundergoes fundamental changes in early infancy, and that a detailedconsideration of the joint influence of neurological and experientialfactors will be necessary to account both for modal patterns of developmentand individual differences in this domain.
Details of individual items:
paper
Can young infants form categorical representations for spatial relations(e.g., above vs. below, left vs. right, between, and inside vs. outside)?The ability to form categorical representations for spatial relations earlyin development should make it possible for infants to experience objects inorganized spatial arrangements, rather than as spatially disconnectedentities located in unrelated positions.Quinn (1994, Child Dev, 65, 58-69) investigated whether 3-month-olds couldform categorical representations for the above and below spatial relationsbetween a dot and a horizontal bar. Infants familiarized with stimulidisplaying the dot in several locations above or below the barpreferentially fixated a stimulus in which the dot appeared on the oppositeside of the bar compared with a stimulus depicting the dot in a novellocation on the same side of the bar. Control experiments revealed that thepreference for the novel spatial relation could not be attributed tospontaneous preference or within-category discrimination failure. Thefindings indicated that the infants had formed categorical representationsfor the above and below spatial relations between the dot and the bar.More recent research has demonstrated that there are at least twodevelopmental changes in infants' abilities to form categoricalrepresentations for spatial relation information. First, categoricalrepresentations of spatial relations may initially be limited to theobjects depicting the relations, but later become more abstract so thatvarious objects can be presented in the same relation and the equivalenceof the relation is maintained despite this variation. For example, in anobject variation version of the above vs. below categorization task, one inwhich the shapes appearing above or below the bar are varied from trial totrial during familiarization and novelty-preference testing, young infants(3- to 4-month-olds) no longer respond preferentially to the novel spatialrelation, indicating that they may encode the spatial relations betweenspecific pairs of objects, but not the spatial relations abstracted acrossa number of different pairs of objects. Older infants (6- to 7-month-olds)do respond preferentially to the novel spatial relation, indicating thatthey are able to represent the abstract versions of the above and belowspatial relations (Quinn et al., 1996, Dev Psych, 32, 942-950).Second, categorical representations for different spatial relations mayemerge at different points during development. In particular, young infants(3 to 4 months of age) have thus far failed to provide evidence that theycan form a representation of between, that is, of a simple shape (e.g.,diamond) appearing in discriminably different locations between two bars,oriented either horizontally as rows or vertically as columns. In contrast,older infants (6 to 7 months of age) perform in a manner indicating thatthey have represented between (Quinn et al., in press, Vis Cog). Theevidence is consistent with a developmental trend in which infantsinitially encode the location of a target relative to a single landmark(e.g., above vs. below), and later encode the location of a target inrelation to multiple landmarks that define a local spatial framework (e.g.,between).Questions of current interest include: (1) whether the trend from specificto more abstract categorical representations for spatial relations isdriven by experience or maturation or both, and (2) whether the formationof categorical representations for other spatial relations will follow thedevelopmental trajectory suggested by the landmark vs. frameworkdistinction.
paper
Infants' coding and processing of spatial information changes markedly inthe first year, and yet the driving forces behind these developments remainpoorly understood. This presentation will review recent evidence thatbody-centered representations of visual direction emerge gradually betweenthree and seven months of age. In addition to reviewing recent evidence fora developmental transition in infants' saccadic eye movements, new evidencewill be presented describing how accurate representations of an observer'sdirection of motion from optic flow also develop slowly in the same timeperiod. These findings support the argument that young infants perceiveseveral important aspects of spatial relations in far simpler terms than doadults, and that the form of young infants' spatial processing changesdramatically in the first several months of life.Explaining why spatial processing changes in these ways is a formidablechallenge. However, infants' behavior on several spatial perception andorienting tasks may be directly associated with the processingcharacteristics of specific systems in the cortex. In adults, these systemssystematically integrate multimodal sources of information about spatialrelationships and contribute to action planning. Accordingly thispresentation will illustrate why brain development is likely to play afundamental role in understanding the emergence of mature spatialprocessing. At the same time, while extensive evidence exist for the roleof active self-produced action in shaping spatial development in the secondsix months of life, little attention has been paid to potentially importantrole of active and passive visual experience in the development of infantsyounger than six months of age. In an effort to bridge this gap, newevidence will be discussed that examines the nature of young infants 'active and passive visual experiences, and their joint influence on spatialdevelopment.
paper
In this presentation research on infants' perception of and reasoning aboutthe spatial and temporal properties of auditory-visual events will bereported. Consideration will be given to:(1) How infants use sound to draw inferences about visible properties ofevents. For example, how do infants utilize temporal and spatial propertiesof sound to draw inferences about which objects is the most likely one tomatch the sound? Do infants show greater reliance on spatial or temporalproperties, and does this vary with age?(2) On what basis do infants come to relate moving audible and visualevents. For example, do infants draw inferences about sight-sound relationsbased on shared properties such as direction of movement and speed ofmovement? Does the basis on which they relate audible and visual eventschange with age?(3) Infants' abilities to utilize spatial as contrasted with temporalproperties to guide learning of arbitrary sight-sound pairings, and togeneralize this learning to new exemplars. For example, once they havelearned that a certain type of sound specifies a particular type of object,does this learning generalize to new exemplars, thereby allowing infants tolearn new auditory-visual relations more quickly? Over what interval oftime, do infants remember the categories of sight-sound relations that theyhave learned? Does this interval vary with age?
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A widely-accepted view of spatial development in the first year is that thecentral accomplishment is a shift from use of an egocentric frame ofreference to use of an allocentric frame of reference. The goal of thispresentation is to question this reading of the existing literature and topresent an alternative position.A first problem with the egocentric-to-allocentric shift hypothesis is thatuse of the terms 'egocentric' and 'allocentric' involves a misleadingdichotomy. Mature spatial behavior can actually be guided by four referencesystems, and three of them can be called 'allocentric'. Specifically, twosystems involve self-reference but only one of these is egocentric. Theegocentric self-referential system can also be called a response learningsystem, and it does not work well when one moves. Another self-referentialsystem, the inertial navigation (or dead reckoning system), updatesposition based on information regarding movement. The twoexternally-referenced systems are cue learning, a system that works onlywhen contiguous cues are available, and place learning, or the use ofdistal landmarks to specify location using distance and directioninformation. Because any shift away from 'egocentrism' may involve a shiftto one, two or all three of the other three 'nonegocentric' systems,research on the egocentric-to- allocentric shift results in confusingoutcomes.A second problem with the egocentric-to-allocentric shift hypothesis isthat developmental change in spatial localization in the first year appearsto be better characterized as a change in the mix of approaches used to aproblem (as in Siegler's 'wave' theory of cognitive development) than as aqualitative shift. There is good evidence that three of the four systemsoutlined above are present early (sensorimotor coding, inertial navigation,and cue learning), but that the probability of each being used changes withexperience in the world, both motoric and visual experience.There is also recent evidence of early underpinnings of dead reckoning (thefourth system), in infant coding of distance in continuous space. However,the formation and evolution of a true dead reckoning system based on suchinformation does not take place until during the second year and continuesits evolution until the age of seven years or so. This developmentaltransition may depend on hippocampal maturation and/or on accumulatingtrial-and-error feedback.Overall, the argument of this paper is not only against a qualitative shifthypothesis, but also against a well-known alternative view, namely, thatfundamental spatial competence is innately specified. The goal of thispresentation is to outline an interactionist account of early spatialdevelopment, different from the traditional stage shift accounts, that yetoffers a non- nativist, interactionist view of development in the spatialdomain.