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Human visuospatial functions are commonly divided into those dependent on the ventral visual stream (ventral occipitotemporal regions), which allows for processing the 'what' of an object, and the dorsal visual stream (dorsal... more
Human visuospatial functions are commonly divided into those dependent on the ventral visual stream (ventral occipitotemporal regions), which allows for processing the 'what' of an object, and the dorsal visual stream (dorsal occipitoparietal regions), which allows for processing 'where' an object is in space. Information about the development of each of the two streams has been accumulating, but very little is known about the effects of injury, particularly very early injury, on this developmental process. Using a set of computerized dorsal and ventral stream tasks matched for stimuli, required response, and difficulty (for typically-developing individuals), we sought to compare the differential effects of injury to the two systems by examining performance in individuals with perinatal brain injury (PBI), who present with selective deficits in visuospatial processing from a young age. Thirty participants (mean=15.1 years) with early unilateral brain injury (15 right...
Children with pre- or perinatal injury to right hemisphere (RH) brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury. Unlike adults, children show considerable... more
Children with pre- or perinatal injury to right hemisphere (RH) brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury. Unlike adults, children show considerable improvement with development on a range of spatial construction tasks which require spatial integration. Such gains could reflect true recovery of spatial integrative abilities. Alternatively, the improvement could
Spatial construction skills were assessed in children with left (LH) or right (RH) hemisphere focal brain injury and control children. Children copied simple and complex block models which were rated on accuracy and spatial strategy. The... more
Spatial construction skills were assessed in children with left (LH) or right (RH) hemisphere focal brain injury and control children. Children copied simple and complex block models which were rated on accuracy and spatial strategy. The accuracy of simple and complex constructions for 4- to 5-year-old children with LH injury was indistinguishable from 4-year-old controls. However, although they were able
Although a few developmental fMRI studies have shed some light on the neurological development of either object or spatial processing we still know very little about the development of the 'what' and 'where' processing... more
Although a few developmental fMRI studies have shed some light on the neurological development of either object or spatial processing we still know very little about the development of the 'what' and 'where' processing systems. The present study is the first to address this issue by comparing, concurrently and within the same behavioral paradigm, patterns of functional activa- tion for
The study was designed to assess the speed and efficiency of visuospatial attentional orienting and the speed of visual processing and motor response in school-age children diagnosed with specific language impairment (SLI). Fifteen... more
The study was designed to assess the speed and efficiency of visuospatial attentional orienting and the speed of visual processing and motor response in school-age children diagnosed with specific language impairment (SLI). Fifteen participants with SLI (7-15 years old) and their gender- and age-matched normally developing peers performed two formats of a simple visual discrimination task, one requiring the use of attentional orienting for accurate performance, and the other not requiring shifts of attention. The SLI group was characterized by (a) slower visual processing, and (b) slower motor response, but (c) similar attentional orienting speed, relative to the control group. The results are discussed in relation to the 'generalized slowing hypothesis' in SLI and the neural underpinning of visuospatial attentional orienting and SLI.
Children with pre- or perinatal injury to right hemisphere (RH) brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury. Unlike adults, children show considerable... more
Children with pre- or perinatal injury to right hemisphere (RH) brain regions show impairment of spatial integrative functions similar to that observed among adults with comparable injury. Unlike adults, children show considerable improvement with development on a range of spatial construction tasks which require spatial integration. Such gains could reflect true recovery of spatial integrative abilities. Alternatively, the improvement could be more limited in scope, reflecting the development of compensatory strategies which are task specific and allow the children to circumvent, rather than overcome, their primary spatial disorders. The studies presented here examined this distinction within the context of drawing tasks in which the child was first asked to draw a house and then an impossible house. The impossible house task was designed to examine the extent to which children rely on graphic formulas in generating organized drawings. The results showed that while all of the children with RH injury make considerable progress in free drawing into the school age period, they are very reliant on the use of graphic formulas. When given a task which requires them to alter their drawings, they did not change the spatial configuration of the depicted object. Rather they found alternate ways to render the object 'impossible'.
Data from parent reports on 1,803 children--derived from a normative study of the MacArthur Communicative Development Inventories (CDIs)--are used to describe the typical course and the extent of variability in major features of... more
Data from parent reports on 1,803 children--derived from a normative study of the MacArthur Communicative Development Inventories (CDIs)--are used to describe the typical course and the extent of variability in major features of communicative development between 8 and 30 months of age. The two instruments, one designed for 8-16-month-old infants, the other for 16-30-month-old toddlers, are both reliable and valid, confirming the value of parent reports that are based on contemporary behavior and a recognition format. Growth trends are described for children scoring at the 10th-, 25th-, 50th-, 75th-, and 90th-percentile levels on receptive and expressive vocabulary, actions and gestures, and a number of aspects of morphology and syntax. Extensive variability exists in the rate of lexical, gestural, and grammatical development. The wide variability across children in the time of onset and course of acquisition of these skills challenges the meaningfulness of the concept of the modal child. At the same time, moderate to high intercorrelations are found among the different skills both concurrently and predictively (across a 6-month period). Sex differences consistently favor females; however, these are very small, typically accounting for 1%-2% of the variance. The effects of SES and birth order are even smaller within this age range. The inventories offer objective criteria for defining typicality and exceptionality, and their cost effectiveness facilitates the aggregation of large data sets needed to address many issues of contemporary theoretical interest. The present data also offer unusually detailed information on the course of development of individual lexical, gestural, and grammatical items and features. Adaptations of the CDIs to other languages have opened new possibilities for cross-linguistic explorations of sequence, rate, and variability of communicative development.
The dramatic changes in cognitive ability observed throughout childhood mirror comparably significant changes in the developing brain. Studies of animals provide important data on associations between the development of behavior and the... more
The dramatic changes in cognitive ability observed throughout childhood mirror comparably significant changes in the developing brain. Studies of animals provide important data on associations between the development of behavior and the neural substrate. However, understanding the development of brain-behavior relations for higher cognitive functions in humans requires direct, concurrent measurement of behavior and brain functions in the children themselves. To date, such data have been very limited. Recent developments in functional magnetic resonance imaging (fMRI) provide the opportunity to systematically explore the development of brain-behavior relations in children. In this article we consider the potential of fMRI to contribute to researchers' understanding of the development of brain-behavior relations. We begin with an overview of the basic imaging method. We then review work from our own laboratory that demonstrates systematic patterns of association between performance on visuospatial tasks and patterns of brain activation, and we compare our findings with those from other laboratories focused on other cognitive domains. Finally, we discuss the potential impact of functional imaging on researchers' understanding of core issues in cognitive and brain development.
In addition to the members of the Editorial Board, the following scholars returned one or more review prior to June 2002. The Editors gratefully acknowledge their generous contributions. ... Jennifer Ackil Karen Adolph Franca Agnoli... more
In addition to the members of the Editorial Board, the following scholars returned one or more review prior to June 2002. The Editors gratefully acknowledge their generous contributions. ... Jennifer Ackil Karen Adolph Franca Agnoli Kristen Alexander Eric Amsel Janette B. Benson Laura Berk Mark Blades Lois Bloom Charles Brainerd Jeremy Carpendale John D. Coley Kevin Crowley Marvin W. Daehler JP Das M. Jeffrey Farrar Cynthia L. Fisher Ross Flom Susan Gelman Gyorgy Gergely Tim German Roberta M. Golinkoff Gail S. Goodman Usha Goswami Catherine ...
in the total area of the callosum relative to matched controls. The area of the total callosum cross-section was inversely proportional to the size of lesion. All patients displayed