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2001

Articles 1 - 9 of 9

Full-Text Articles in Neurosciences

Can Meaningful Effective Connectivities Be Obtained Between Auditory Cortical Regions?, M S Gonçalves, D A Hall, Ingrid Johnsrude, M P Haggard Dec 2001

Can Meaningful Effective Connectivities Be Obtained Between Auditory Cortical Regions?, M S Gonçalves, D A Hall, Ingrid Johnsrude, M P Haggard

Brain and Mind Institute Researchers' Publications

Structural equation modeling (SEM) of neuroimaging data can be evaluated both for the goodness of fit of the model and for the strength of path coefficients (as an index of effective connectivity). SEM of auditory fMRI data is made difficult by the necessary sparse temporal sampling of the time series (to avoid contamination of auditory activation by the response to scanner noise) and by the paucity of well-defined anatomical information to constrain the functional model. We used SEM (i.e., a model incorporating latent variables) to investigate how well fMRI data in four adjacent cortical fields can be described as an …

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New Procedures To Assess Executive Functions In Preschool Children, K. A. Espy, P. M. Kaufmann, M. L. Glisky, M. D. Mcdiarmid Nov 2001

New Procedures To Assess Executive Functions In Preschool Children, K. A. Espy, P. M. Kaufmann, M. L. Glisky, M. D. Mcdiarmid

Developmental Cognitive Neuroscience Laboratory: Faculty Publications

Executive functions are difficult to assess in preschool children, yet the preschool period is particularly important, both in the development of behavioral control and of the brain, particularly the prefrontal cortex. Several tasks were adapted from developmental and neuroscience literature and then administered to 98 preschool children (30-, 36-, 42-, 48- and 60-month age groups). Executive function task performance was related largely to age group, but not to sex or intelligence. These tasks, then, were sensitive in this age range and may be useful to delineate distinct cognitive profiles among preschool children with various neurological and developmental disorders.

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Chemotherapeutic Cns Prophylaxis And Neuropsychologic Change In Children With Acute Lymphoblastic Leukemia: A Prospective Study, K. A. Espy, I. M. Moore, P. M. Kaufmann, J. H. Kramer, K. Matthay, J. J. Hutter Nov 2001

Chemotherapeutic Cns Prophylaxis And Neuropsychologic Change In Children With Acute Lymphoblastic Leukemia: A Prospective Study, K. A. Espy, I. M. Moore, P. M. Kaufmann, J. H. Kramer, K. Matthay, J. J. Hutter

Developmental Cognitive Neuroscience Laboratory: Faculty Publications

OBJECTIVE: To determine whether prophylactic CNS chemotherapy for childhood acute lymphoblastic leukemia is associated with declines in neuropsychological abilities. METHODS: Growth curve analysis was used to examine neuropsychological outcome and treatment-related change in children (N = 30) who were treated at two childhood cancer centers. A comprehensive test battery was administered at baseline (8 months), 2, 3, and 4 years postdiagnosis (age at diagnosis M = 5.90 years, SD = 4.2C). RESULTS: Results indicated modest declines in arithmetic, visual motor integration, and verbal fluency. Intrathecal and systemic treatment was related to poorer visual motor integration at 4 years postdiagnosis and …

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Ipsilesional Biases In Saccades But Not Perception After Lesions Of The Human Inferior Parietal Lobule, Tony Ro, Chris Rorden, Jon Driver, Robert Rafal Oct 2001

Ipsilesional Biases In Saccades But Not Perception After Lesions Of The Human Inferior Parietal Lobule, Tony Ro, Chris Rorden, Jon Driver, Robert Rafal

Publications and Research

We examined the effects of chronic unilateral lesions to either the inferior parietal lobe, or to the dorsolateral prefrontal cortex including the frontal eye fields (FEFs), upon human visual perception and saccades in temporal-order-judgment (TOJ) tasks. Two visual events were presented on each trial, one in each hemifield at various stimulus onset asynchronies (SOAs). In the saccade task, patients moved their eyes to whichever stimulus attracted gaze first. In the perceptual-manual task, they pressed a button to indicate which stimulus was perceived first. Frontal patients showed appropriate TOJs for visual targets in both tasks. Parietal patients showed appropriate TOJs in …

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Discrimination Of Computer-Graphic Stimuli By Mice: A Method For The Behavioral Characterization Of Transgenic And Gene-Knockout Models., T J Bussey, L M Saksida, L A Rothblat Aug 2001

Discrimination Of Computer-Graphic Stimuli By Mice: A Method For The Behavioral Characterization Of Transgenic And Gene-Knockout Models., T J Bussey, L M Saksida, L A Rothblat

Brain and Mind Institute Researchers' Publications

An automated method is described for the behavioral testing of mice in an apparatus that allows computer-graphic stimulus material to be presented. Mice responded to these stimuli by making a nose-poke toward a computer monitor that was equipped with a touchscreen attachment for detecting responses. It was found that C57BL/6 mice were able to solve single-pair visual discriminations as well as 3-pair concurrent visual discriminations. The finding that mice are capable of complex visual discriminations introduces the possibility of testing mice on nonspatial tasks that are similar to those used with rats, monkeys, and humans. Furthermore, the method seems particularly …

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The Structure And Biological Features Of Fibrinogen And Fibrin, Michael W. Mosesson, Kevin R. Siebenlist, David A. Meh Jun 2001

The Structure And Biological Features Of Fibrinogen And Fibrin, Michael W. Mosesson, Kevin R. Siebenlist, David A. Meh

Biomedical Sciences Faculty Research and Publications

Fibrinogen and fibrin play important, overlapping roles in blood clotting, fibrinolysis, cellular and matrix interactions, inflammation, wound healing, and neoplasia. These events are regulated to a large extent by fibrin formation itself and by complementary interactions between specific binding sites on fibrin(ogen) and extrinsic molecules including proenzymes, clotting factors, enzyme inhibitors, and cell receptors. Fibrinogen is comprised of two sets of three polypeptide chains termed Aα, Bβ, and γ, that are joined by disulfide bridging within the N-terminal E domain. The molecules are elongated 45-nm structures consisting of two outer D domains, each connected to a central E domain by …

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Neuromotor And Cognitive Development In Children With Cerebral Palsy In Relation To Neural Plasticity, Vaniecea Pollard May 2001

Neuromotor And Cognitive Development In Children With Cerebral Palsy In Relation To Neural Plasticity, Vaniecea Pollard

McCabe Thesis Collection

Infants with neurological disabilities, such as cerebral palsy (CP) and Down syndrome (DS), show severe delays in motor and cognitive development relative to chronological age. Involvement of neural plasticity as a treatment of such neurological disorders is increasingly being seen. Previous studies have found that interventions involving sensory linked motor performance have been critical in facilitating motor improvement. The purpose of this study was to compare self-initiated mobility in children with CP and DS. Three infants, ages 8, 9, and 22 months, with diagnoses of no CP, DS, and CP respectively, participated in the study. The infants were videotaped in …

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Increased Mrna Expression For The Α1 Subunit Of The GabaA Receptor Following Nitrous Oxide Exposure In Mice, Lisa M. Johanek, William E. Cullinan, Linda K. Vaughn Apr 2001

Increased Mrna Expression For The Α1 Subunit Of The GabaA Receptor Following Nitrous Oxide Exposure In Mice, Lisa M. Johanek, William E. Cullinan, Linda K. Vaughn

Biomedical Sciences Faculty Research and Publications

The mechanisms by which nitrous oxide (N2O) produces physical dependence and withdrawal seizures are not well understood, but both N2O and ethanol exert some of their effects via the GABAA receptor and several lines of evidence indicate that withdrawal from N2O and ethanol may be produced through similar mechanisms. Expression levels of mRNA transcripts encoding several GABAA receptor subunits change with chronic ethanol exposure and, therefore, we hypothesized that N2O exposure would produce changes in mRNA expression for the α1 subunit. Male, Swiss–Webster mice, 10–12 weeks of age, were …

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Eye Position Sense Contributes To The Judgement Of Slant., F M James, S Whitehead, G K Humphrey, M S Banks, T Vilis Jan 2001

Eye Position Sense Contributes To The Judgement Of Slant., F M James, S Whitehead, G K Humphrey, M S Banks, T Vilis

Brain and Mind Institute Researchers' Publications

We measured monocular judgements of the slant of a cube face while varying eye position in the absence of stereoscopic and external lighting cues. Errors were found to be small, only 10% on average of the cube's eccentricity. Two factors appear to have contributed approximately equally to this error: an underestimate of cube slant as seen by the eye and an underestimate of eye position. When prism adaptation altered the sensed eye position, the pattern of slant judgements changed to reflect the altered sense of eye position.

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