Janellen Huttenlocher, Ph.D. - US grants

The proposed research is concerned with an important aspect of autobiographical memory - the ability to remember when events occurred. It seems clear that a memorial record which preserves the temporal continuity of a person's experience is central to intellectual functioning as well as to a coherent view of the self. Yet major theoretical issues concerning temporal memory have not been explored, and systematic empirical studies remain to be carried out. Available data indicate that, while the time of occurrence of events is preserved in memory to some extent, there is substantial inexactness and bias in temporal reports. In the proposed research, we aim to explore and explain observed biases in temporal reports. The studies outlined below emerge from our recent work on the consequences of hierarchical organization in memory in ordered domains, including temporal memory. Time is divided into units of various sizes (hours, days, weeks). When information is inexact at the level of detail required to answer a question, information from larger temporal units may affect estimation, leading to bias in reporting. Preliminary evidence suggests that bias is a consequence of inexactness in memory and increases over time. We have developed two quantitative models which specify ways in which information at different levels of detail is combined in producing temporal reports. We propose to carry out a set of studies which provide systematic information on inexactness and bias in reporting. The immediate goal is to examine if the models fully account for observed bias. Explaining the sources of bias will contribute to our theoretical goal of understanding how temporal information is represented in memory, and of the retrieval and estimation processes involved in answering temporal questions. It may also contribute to the practical problem of developing methods to collect more accurate social and health related data involving temporal reports.

9222073 HUTTENLOCHER This research concerns children's ability to remember the locations of objects. Remembering where things are in the world has very clear adaptive importance. Yet, somewhat surprisingly, the well- known work of Piaget claimed that children younger than 9 or 10 years remember location only in terms of whether something touches or is close to a landmark, but not in terms of distance. This description of spatial development has guided much subsequent thinking about curricula in areas such as geography, map-reading, and geometry. However, recent work using new techniques suggests that, by as early as 16 months, children can indeed encode distance accurately. In addition, the small errors they do make show a pattern of systematic bias that suggests that, like adults, children of this age encode location in terms of spatial categories, as well as at a more fine-grained level, combining the two levels when they search for objects. This process can be called hierarchical coding. The first group of new experiments will test the hypothesis that children use hierarchical coding from a very early time, by excluding several other accounts of their bias patterns. The second line of work will use a new paradigm to investigate coding of distance as early as 4 months. Infants of this age cannot crawl, and are just beginning to reach, so finding distance coding at this time would suggest that crawling and reaching are not vital to such coding (as Piaget and others have suggested). A third set of experiments will establish the nature of the categories used in hierarchical coding, in particular, whether the probability and extent of subdivision of larger spaces increases with age. The fourth line of work will focus on biases in spatial judgment, aimed at testing the hypothesis that these occur when spaces are subdivided. Taken together, the work should establish a new theoretical account of spatial development. ***

This project is being funded through the Learning and Intelligent Systems (LIS) Initiative. A group of nine senior investigators will study spatial competence, and its emergence over time, at the cognitive, computational, and neural levels. Topics to be studied include how people form spatial representations; how people communicate about spatial information using external symbol systems such as maps, diagrams, graphs, and linguistic descriptions; the role of the educational input received in American schools in supporting spatial learning; the optimal computational model of spatial learning; and, evidence of neural plasticity for spatial learning, based on both neuroanatomical study and neuropsychological evaluation. The common purpose of this group of related research endeavors is to examine the nature of environmentally-sensitive growth in spatial competence and how spatial learning can be maximized in the American population. Innovations for educational practice and educational software resulting from our research will be evaluated with the help of collaborating teachers.

Human beings, like all organisms that move in the world, must remember
the location of objects and goals in order to live successfully. Unlike
other organisms, human beings can learn about locations both
symbolically and through direct experience. The goal of this research
program is to understand the development of spatial competence.

Recent work has shown that many spatial skills arise earlier in
development than had hitherto been supposed. However, early success may
reflect the use of simple processes, different from mature coding,
rather than innate specification of spatial competence. Three sets of
studies will be carried out to address this general issue. In one line
of work, the focus is on the nature of infant location coding as
inferred from their looking times to events. In a second line of work,
the aim is to evaluate a recent claim that children show evidence of an
innately-specified "geometric module" in their searches for hidden
objects. The third line of work will examine how children use simple
maps to find hidden objects.

Finding evidence for developmental transformations in spatial
development as well as for strong initial starting points is important
theoretically, as it provides support for a position in which biological
specification and environmental interaction interact to produce
development. In practical terms, support for such a position would
indicate that certain environmental experiences may be necessary for
normal development, and could even be manipulated to allow optimal
development.

Spatial competence is a fundamental aspect of intelligence,
important to successful functioning. A high level of spatial skill
is critical to the achievement of a technologically sophisticated
work force for the twenty-first century. Spatial intelligence plays
a major role in effective education in mathematics, science and
engineering. The interdisciplinary research we will carry out
focuses on understanding of spatial intelligence and establishing
methods for maximizing the development of spatial skills. We will
study spatial competence at different levels of analysis. At the
biological level, we will will investigate the neurological
foundations for spatial growth. We will examine the growth and
organization of neural connections in areas of the brain that
underlie the processing of spatial information. At the behavioral
level, we will investigate the mechanisms that are involved in the
mental representation of the spatial aspects of the world. We also
will study the ways in which children come to understand spatial
symbols such as maps and models. We will study how acquisition of
these symbol systems affects the development of spatial intelligence.
This work will include computational modelling of spatial
intelligence. Finally, at the level of educational application, we
will investigate the educational input responsible for the
differential gains in spatial skill levels children achieve in
school. We plan to identify specific teacher practices that are
associated with high gains in student achievement. Our research team
has expertise in a variety of relevant fields, including neural
science, cognitive psychology, developmental psychology,computer
science, education, and statistics. This research team has worked
together for the past three years on research that has identified
core elements of spatial functioning. Our goal now is to further our
understanding of how the development of spatial competence can be
enhanced .M

DESCRIPTION: (provided by applicant) Acquiring the ability to communicate using natural language and symbolic gestures is a uniquely human capacity that underlies the exchange of information among people. There is as yet no consensus concerning how susceptible this process is to environmental and biological variation. The proposed Program Project focuses on this issue, exploring the extent and the limits of the language-learning process. To examine language growth in the face of environmental variation (Project I), a group of children selected to reflect the demographic distribution within the Chicago area will be observed longitudinally, both at home and at daycare, with an eye toward determining the relation between variations in the speech of caregivers and variations in children's language skills. Assessments will be made of child production and comprehension, and adult input, at 4-month intervals from 14 to 58 mos. Using these data, growth curves will be constructed for each child to track language development across time, and to examine the child's linguistic progress in relation to changes in input. To explore language growth in the face of biological variation (Project III), a group of children with unilateral brain injury will be observed from 14 to 58 mos. with an eye toward describing their language growth, and determining whether environmental variation plays the same role in predicting their growth as it does in children who have not suffered brain injury. Along with traditional measures, two additional probes will be used. (1) The child's communicative competence, and the child's communicative input, will be assessed using gesture as well as speech (Project II). Gesture will be examined in both the brain injured and intact groups to determine whether children who are delayed in speech relative to their peers use gesture to compensate for those delays, and to determine whether the gestures caregivers produce along with their own speech predict individual differences in child language growth. (2) The brain bases underlying communicative competence will be assessed using fMRI techniques (Project IV). The linguistic and gestural skills of individuals who have suffered brain injury at different points in their development will be assessed; fMRI probes will then be used to determine which cortical areas are involved in linguistic and gestural functioning following brain injury occurring at different ages. Three cores provide broad support to the projects: the Administrative Core A, the Data Collection and Transcription Core B, and the Statistical Core C.

Research over the past two decades has revealed that a wide variety of animal species, including fish, birds, non-human mammals and humans, share a powerful sensitivity to the geometric properties of enclosing spaces (e.g., the relative length of walls defining enclosures). They use such information to reestablish spatial orientation after being disoriented (Cheng, 1986; Hermer & Spelke, 1996; for a review, see Cheng & Newcombe, in press). Further, it has been suggested that such geometric processing constitutes a specialized cognitive module that is normally impenetrable to nongeometric information (Cheng, 1986; Hermer & Spelke, 1996), with combination of information only made possible by use of language (Spelke & Hermer, 1996). These findings on geometric processing and its purported modularity have been exciting to a wide audience of researchers focused on cognitive architecture, comparative cognition, cognitive development, and the role of language in behavior. They are relevant to the hotly-debated issues concerning the extent to which knowledge is innate or environmentally plastic. Parents, educators and policy makers have a stake in accurate understanding of the nature of development.

Vital issues concerning these proposals remain unsettled, however. This research will address controversy in two areas. First, the nature of geometric sensitivity is not yet clear. We will address two questions: how geometric coding is related to representations of viewer position, and whether information about the lengths of the sides of a space is retained in an absolute way (as some mental equivalent of a measured distance) or in a relative fashion (as some lengths being simply longer or shorter than others). Second, there is doubt about the claim that geometric information is encapsulated and the associated idea that landmarks are not integrated with geometric information unless language is used to link cognitive modules. An alternative account holds that geometric and featural information are normally integrated in a way that depends on the relative usefulness of various kinds of information in particular situations. This research project will contrast these accounts.

DESCRIPTION (provided by applicant): The goal of this training program is to train four predoctoral students and up to four postdoctoral fellows each year in a broadly based program in developmental science at the University of Chicago. Trainees engage in a wide range of laboratory and field-based research that will enable them to conduct research on the basic science of development and to participate in serious ways in addressing and solving pressing practical problems. The program offers students exposure to a variety of studies and techniques, including experimental and naturalistic studies of infants, toddlers, and older children, gesture and narrative analysis, computational analysis, neuro-endocrine techniques, brain-imaging and electrophysiological techniques, and ethnographic studies. The program is comprised of a core of developmental faculty who are joined by additional faculty members with substantive interests in developmental issues. The training faculty focuses on three main content areas of research: cognitive, language, and social development. Across these content areas, the faculty investigates development at different levels of analysis -- the levels of individual psychological development, of biological influences on development, and of the social/contextual factors affecting development. The training faculty has a long tradition of collaborative research and teaching. Thus, students are exposed to multiple perspectives within each developmental research area, and they often engage in interdisciplinary research. The predoctoral program offers trainees a strong grounding in experimental psychology and provides specialized training in developmental science through courses, seminars, and research experiences. Predoctoral trainees and postdoctoral trainees attend the weekly developmental seminar. Postdoctoral trainees will have at least two mentors from the training faculty and will join a rich environment for postdoctoral investigations in the Department of Psychology.

Development of the ability to read and to process complex spoken language is critical for academic success. Yet many individuals have low reading and oral language skills and thus may be poorly equipped to meet the challenges of our complex society. The existing literature suggests that the growth of reading and later language may be affected by early language and pre-reading skills, and by home environments. Indeed, it has been suggested that early disparities among children will remain or even increase over the school years ("The Matthew Effect"). However, the issue remains to be systematically explored, since studies of school achievement in relation to early experience have been lacking. We have recently carried out a longitudinal study of language growth in a diverse sample of children from 14 to 58 months. We propose to study these children over the school-age years. The proposed research is unique in its examination of language growth and reading in children from a wide variety of backgrounds whose early language and pre-reading skills have been examined in detail. Aim 1. We propose to extend our study of language growth by evaluating children's language over a longer period of language growth, examining their narrative skills as well as vocabulary and complex syntax. We will explore the patterns of development from 14 months until 10 years. Data from the first five year study showed sizeable individual differences and a substantial relation to caregiver input. In the next period of the grant, we will examine individual differences in oral language levels in the school-age years, exploring possible discontinuities in growth rates, reflecting, for example, growth of reading comprehension. The results of the proposed study should provide a more reasoned basis for decisions as to when and how to intervene to increase language skills of the population. Aim 2. We propose to examine how early language, pre-reading skills, and home environments are implicated in school learning. Preschool growth measures will be used as predictors, allowing us to distinguish among children with similar scores at one time point, but different patterns of growth. This is important because different input histories may have different implications for later learning. Outcome measures involve both reading and oral language. The data will allow us to systematically examine if discrepancies among children increase over the school years, as might be expected if children with better skills at the time of school entry learn more at school. Alternatively, since higher-performing children show greater growth over the summer than lower-performing children, this summer difference alone could explain the Matthew Effect. In order to pinpoint the sources of differences among children, we examine growth separately over the school year and summer. Investigation of predictors of individual differences should contribute to our understanding of ways to overcome the effects of poor early environments.