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M Westerveld

Publications and source records attributed to M Westerveld.

At least 19 recordsLinked to original sources
PubMed2006

The factor structure of the CVLT-C in pediatric epilepsy.

The current study used archival data to evaluate the fit of six latent variable models, originally generated by Donders (1999), for the California Verbal Learning Test-Children's Version (CVLT-C; Delis, Kramer, Kaplan, & Ober, 1994) in a large (N = 289) sample of pediatric epilepsy cases presenting at three tertiary treatment centers. Using confirmatory factor analysis, we found that a model including factors of Attention Span, Learning Efficiency, Free Delayed Recall, Cued Delayed Recall, and Inaccurate Recall demonstrated the best relative fit for our data. These findings are consistent with those reported by Donders (1999) in his reanalysis of the CVLT-C standardization sample data, supporting the validity of this factorial model in pediatric epilepsy populations.

Adolescent↗
PubMed2005

Neural correlates of temporal-order judgments versus those of spatial-location: deactivation of hippocampus may facilitate spatial performance.

The retrieval of temporal-order versus spatial-location information was investigated using fMRI. The primary finding in the hippocampus proper, seen in region of interest analyses, was an increase in BOLD signal intensity for temporal retrieval, and a decrease in signal intensity for spatial retrieval, relative to baseline. The negative BOLD signal change with spatial memory processing, while unexpected, is consistent with the recent fMRI literature indicating decreased BOLD can be associated with neuronal activation, and it is argued that the deactivation observed here may facilitate spatial performance. Spatial-location judgments also yielded a stronger (positive) response in the right midfrontal gyrus, while temporal-order judgments (autobiographic condition only) showed greater activity in the left superior temporal gyrus, suggesting greater working memory demands and greater semantization for each judgment type, respectively. Finally, all conditions activated the left midfrontal gyrus, although autobiographic memories showed additional activity in the medial frontal gyrus.

Adult↗
PubMed2001

Functional MRI of language processing: dependence on input modality and temporal lobe epilepsy.

PURPOSE: Functional magnetic resonance imaging (MRI) using two language-comprehension tasks was evaluated to determine its ability to lateralize language processing and identify regions that must be spared in surgery. METHODS: Two parallel cognitive language tasks, one using auditory input and the other visual input, were tested in a group of control subjects and in temporal lobe epilepsy patients who were candidates for surgical intervention. The patient studies provide an opportunity to compare functional MRI language localization with that obtained using Wada testing and electrocorticography. All of the patients in this study underwent all three procedures and a battery of neuropsychological testing. Such studies provide an opportunity not only to validate the fMRI findings but also, by comparing the patient results with those obtained in control subjects, to provide insight into the impact of a pathology such as epilepsy on cortical organization or functional patterns of activation. RESULTS: The results reveal both modality-dependent and modality-independent language-processing patterns for visual versus auditory task presentation. The visual language task activated distinct sites in Broca's area, BA (Brodmann area) 44 that were not activated in the auditory language task. The auditory language task strongly activated contralateral right BA22-21 area (homologous to Wernicke's area on the left). Language lateralization scores were significantly stronger for visual than for auditory task presentation. The conjunction of activation from the two different input modalities (modality-independent areas) likely highlights regions that perform more abstract computations (e.g., syntactic or pragmatic processing) in language processing. Modality-specific areas (e.g., right Wernicke, left fusiform gyrus, Broca BA44, supramarginal gyrus), appear to cope with the computations relevant to making contact with these more abstract dimensions. Patients showed recruitment of contralateral homologous language areas (p < 0.005) that was significantly above that found in a normal control group. Extra- and intraoperative cortical stimulations were concordant with the fMRI data in eight of 10 cases. The fMRI lateralization scores were also consistent with the Wada testing in 8/10 patients. CONCLUSIONS: The fMRI results demonstrate that the epileptic brain may be a progressive model for cortical plasticity.

Adult↗
PubMed2000

Regional brain volume abnormalities and long-term cognitive outcome in preterm infants.

CONTEXT: Preterm infants have a high prevalence of long-term cognitive and behavioral disturbances. However, it is not known whether the stresses associated with premature birth disrupt regionally specific brain maturation or whether abnormalities in brain structure contribute to cognitive deficits. OBJECTIVE: To determine whether regional brain volumes differ between term and preterm children and to examine the association of regional brain volumes in prematurely born children with long-term cognitive outcomes. DESIGN AND SETTING: Case-control study conducted in 1998 and 1999 at 2 US university medical schools. PARTICIPANTS: A consecutive sample of 25 eight-year-old preterm children recruited from a longitudinal follow-up study of preterm infants and 39 term control children who were recruited from the community and who were comparable with the preterm children in age, sex, maternal education, and minority status. MAIN OUTCOME MEASURES: Volumes of cortical subdivisions, ventricular system, cerebellum, basal ganglia, corpus callosum, amygdala, and hippocampus, derived from structural magnetic resonance imaging scans and compared between preterm and term children; correlations of regional brain volumes with cognitive measures (at age 8 years) and perinatal variables among preterm children. RESULTS: Regional cortical volumes were significantly smaller in the preterm children, most prominently in sensorimotor regions (difference: left, 14.6%; right, 14.3% [P<.001 for both]) but also in premotor (left, 11.2%; right, 12.6% [P<.001 for both]), midtemporal (left, 7.4% [P =.01]; right, 10.2% [P<.001]), parieto-occipital (left, 7.9% [P =.01]; right, 7.4% [P =.005]), and subgenual (left, 8.9% [P =.03]; right, 11.7% [P =.01]) cortices. Preterm children's brain volumes were significantly larger (by 105. 7%-271.6%) in the occipital and temporal horns of the ventricles (P<. 001 for all) and smaller in the cerebellum (6.7%; P =.02), basal ganglia (11.4%-13.8%; P</=.005), amygdala (left, 20.2% [P =.001]; right, 30.0% [P<.001]), hippocampus (left, 16.0% [P =.001]; right, 12.0% [P =.007]), and corpus callosum (13.1%-35.2%; P</=.01 for all). Volumes of sensorimotor and midtemporal cortices were associated positively with full-scale, verbal, and performance IQ scores (P<.01 for all). CONCLUSIONS: Our data indicate that preterm birth is associated with regionally specific, long-term reductions in brain volume and that morphological abnormalities are, in turn, associated with poorer cognitive outcome. JAMA. 2000;284:1939-1947.

Brain↗
PubMed2000

Investigation of the human hippocampal formation using a randomized event-related paradigm and Z-shimmed functional MRI.

Functional neuroimaging of the hippocampal formation has presented a challenge to neuroscientists because of the small size of the hippocampus proper and its location at the basal level of the brain. Choosing the appropriate control condition for subtraction-based studies has also proved difficult. Event-related experimental designs are a powerful tool in behavioral and electrophysiological studies. Recently, such experimental designs have been applied to functional MR imaging studies but these studies used large intertrial intervals in order to separate the slow blood flow response from temporally adjacent events, severely limiting the number of events that can be presented in a single run. This leads to poor statistical power and restrictions on the design of the experimental paradigm. We present data obtained using a rapidly presented, randomized event-related paradigm, combined with a novel fMRI imaging method designed to improve imaging in basal brain regions. The results demonstrate bilateral activation in the hippocampal formation in identification of novel complex scenes distinct from a learned basis set of complex scenes. Differential activation is obtained in the counter task of identifying a learned target complex scene against a background of novel scenes. The results are also compared with the more conventional block design complex scene paradigms previously reported by others. The block design provides strong posterior activation, likely related more to visual scene processing, whereas the event-related design provides more anterior hippocampal activation with the encoding of novel scenes.

Adult↗
PubMed2000

Outcome of children in the indomethacin intraventricular hemorrhage prevention trial.

BACKGROUND: For preterm infants, intraventricular hemorrhage (IVH) may be associated with adverse neurodevelopmental outcome. We have demonstrated that early low-dose indomethacin treatment is associated with a decrease in both the incidence and severity of IVH in very low birth weight preterm infants. In addition, we hypothesized that the early administration of low-dose indomethacin would not be associated with an increase in the incidence of neurodevelopmental handicap at 4.5 years of age in our study children. METHODS: To test this hypothesis, we provided neurodevelopmental follow-up for the 384 very low birth weight survivors of the Multicenter Randomized Indomethacin IVH Prevention Trial. Three hundred thirty-seven children (88%) were evaluated at 54 months' corrected age, and underwent neurodevelopmental examinations, including the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), the Peabody Picture Vocabulary Test-Revised (PPVT-R), and standard neurologic examinations. RESULTS: Of the 337 study children, 170 had been randomized to early low-dose indomethacin therapy and 167 children had received placebo. Twelve (7%) of the 165 indomethacin children and 11 (7%) of the 158 placebo children who underwent neurologic examinations were found to have cerebral palsy. For the 233 English-monolingual children for whom cognitive outcome data follow, the mean gestational age was significantly younger for the children who received indomethacin than for those who received placebo. In addition, although there were no differences in the WPPSI-R or the PPVT-R scores between the 2 groups, analysis of the WPPSI-R full-scale IQ by function range demonstrated significantly less mental retardation among those children randomized to early low-dose indomethacin (for the indomethacin study children, 9% had an IQ <70, 12% had an IQ of 70-80, and 79% had an IQ >80, compared with the placebo group, for whom 17% had an IQ <70, 18% had an IQ of 70-80, and 65% had an IQ >80). Indomethacin children also experienced significantly less difficulty with vocabulary skills as assessed by the PPVT-R when compared with placebo children. CONCLUSIONS: These data suggest that, for preterm neonates, the early administration of low-dose indomethacin therapy is not associated with adverse neurodevelopmental function at 54 months' corrected age.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

Temporal lobectomy in children: cognitive outcome.

OBJECT: The authors sought to determine the impact of early temporal lobectomy (in patients younger than age 17 years) on intellectual functioning. The efficacy of temporal lobectomy for treating seizures is well established and the procedure is becoming more acceptable as a treatment for children whose seizures are intractable. However, cognitive outcomes of temporal lobectomy in children and adolescents are largely unreported. The present study takes advantage of a unique multicenter collaboration to examine retrospectively intellectual functioning in a large sample of children who underwent temporal lobectomy. METHODS: Intellectual functioning was assessed before and after temporal lobectomy for treatment of medication-resistant seizures in 82 patients at eight centers of epilepsy surgery. All children underwent standard presurgical examinations, including electroencephalography-video monitoring, magnetic resonance (MR) imaging, and neuropsychological testing, at their respective centers. Forty-three children underwent left temporal lobectomy and 39 underwent right temporal lobectomy. For the entire sample, there were no significant declines in intelligence quotient (IQ) following surgery. Children who underwent left temporal lobectomy demonstrated no significant loss in verbal intellectual functioning and improved significantly in nonverbal intellectual functioning. Children who underwent right temporal lobectomy did not demonstrate significant changes in intellectual functioning. Although group scores showed no change in overall IQ values, an analysis of individual changes revealed that approximately 10% of the sample experienced a significant decline and 9% experienced significant improvement in verbal functioning. Significant improvement in nonverbal cognitive function was observed in 16% of the sample and only 2% of the sample showed significant declines. Risk factors for significant decline included older patient age at the time of surgery and the presence of a structural lesion other than mesial temporal sclerosis on MR imaging. CONCLUSIONS: The present study provides preliminary data for establishing the risk of cognitive morbidity posed by temporal lobectomy performed during childhood. With respect to global intellectual functioning, a slight improvement was significantly more likely to occur than a decline. However, there were several patients in whom significant declines did occur. It will be necessary to study further the factors associated with such declines. In addition, further study of more specific cognitive functions, particularly memory, is needed.

Adolescent↗
PubMed1999

Effects of anomalous language representation on neuropsychological performance in temporal lobe epilepsy.

OBJECTIVE: To examine the effects of anomalous language representation (i.e., mixed- and right-cerebral dominant) on neuropsychological performance. BACKGROUND: Right cerebral language dominance resulting from early cerebral injury is associated with relatively preserved language function with decreased visuospatial ability. However, previous reports of this phenomenon have examined patients with relatively large cerebral injuries (e.g., infantile hemiplegia) or limited sample sizes. METHODS: A total of 561 patients with complex partial seizures of left temporal lobe origin were studied. Patients were classified into left (n = 455), bilateral (n = 58), and right (n = 48) language dominant groups based on Wada testing. RESULTS: Right language dominant patients performed more poorly on multiple tests of visuospatial function, including Performance IQ (PIQ), than did left language patients. No significant group differences were detected for measures of language or general verbal function. The effects of bilateral language on PIQ differed according to handedness. Lowered PIQ was present in the bilateral nondextral group but not for bilateral dextral patients, and this pattern was observed with other visuospatial measures. CONCLUSIONS: In patients with relatively small lesions restricted to the left mesial temporal lobe, a shift in language dominance to the right hemisphere is associated with decreased visuospatial functions but preserved verbal abilities. Nondextral patients with bilateral language representation also displayed decreased visuospatial performance, although dextral patients with bilateral language did not.

Adult↗
PubMed1999

Visual confrontation naming following left anterior temporal lobectomy: a comparison of surgical approaches.

Change in visual confrontation naming was examined following left (speech dominant) anterior temporal lobectomy (ATL) as a function of surgical technique and patient characteristics. Two hundred seventeen patients with intractable left temporal lobe epilepsy were selected according to standard criteria across 8 centers, and combined into 4 surgical approaches to ATL: (a) tailored resections with intraoperative mapping of eloquent cortex, (b) tailored resections with extraoperative mapping, (c) standard resections with sparing of superior temporal gyrus, and (d) standard resections including excision of superior temporal gyrus. Changes in visual confrontation naming were examined with an index of reliable change derived from an independent sample of 90 nonsurgical patients with complex partial seizures. Results showed significant decline in visual confrontation naming following left ATL, regardless of surgical technique. Across surgical approaches, the risk for decline in visual confrontation naming was associated with a later age of seizure onset and more extensive resection of lateral temporal neocortex.

Adult↗
PubMed1999

The etiology and outcome of cerebral ventriculomegaly at term in very low birth weight preterm infants.

BACKGROUND: Despite improvements in survival data, the incidence of neurodevelopmental handicaps in preterm infants remains high. To prevent these handicaps, one must understand the pathophysiology behind them. For preterm infants, cerebral ventriculomegaly (VM) may be associated with adverse neurodevelopmental outcome. We hypothesized that although the causes of VM are multiple, the incidence of handicap at 4.5 years of age in preterm infants with this ultrasonographic finding at term would be high. METHODS: To test this hypothesis, we provided neurodevelopmental follow-up for all 440 very low birth weight survivors of the Multicenter Randomized Indomethacin Intraventricular Hemorrhage (IVH) Prevention Trial. A total of 384 children (87%) were evaluated at 54 months' corrected age (CA), and 257 subjects were living in English-speaking, monolingual households and are included in the following data analysis. RESULTS: Moderate to severe low pressure VM at term was documented in 11 (4%) of the English-speaking, monolingual survivors. High grade IVH and bronchopulmonary dysplasia (BPD) were both risk factors for the development of VM. Of 11 (45%) children with VM, 5 suffered grades 3 to 4 IVH, compared with 2/246 (1%) children without VM who experienced grades 3 to 4 IVH. Similarly, 9/11 (82%) children with VM had BPD, compared with 120/246 (49%) children without VM who had BPD. Logistic regression analysis was performed using birth weight, gestational age, gender, Apgar score at 5 minutes, BPD, sepsis, moderate to severe VM, periventricular leukomalacia, grade of IVH, and maternal education to predict IQ <70. Although maternal education was an important and independent predictor of adverse cognitive outcome, in this series of very low birth weight prematurely born children, VM was the most important predictor of IQ <70 (OR: 19.0; 95% CI: 4.5, 80.6). Of children with VM, 6/11 (55%) had an IQ <70, compared with 31/246 (13%) of children without VM. Children with VM had significantly lower verbal and performance scores compared with children without VM. CONCLUSIONS: These data suggest that, for preterm neonates, VM at term is a consequence of the vulnerability of the developing brain. Furthermore, its presence is an important and independent predictor of adverse cognitive and motor development at 4.5 years' CA.

Bronchopulmonary Dysplasia↗
PubMed1998

Does presurgical IQ predict seizure outcome after temporal lobectomy? Evidence from the Bozeman Epilepsy Consortium.

PURPOSE: Considerable debate exists concerning whether the presence of low preoperative IQ should be a contraindication for focal resective epilepsy surgery. METHODS: We examined the relationship between baseline IQ scores and seizure outcome in 1,034 temporal lobectomy cases from eight epilepsy surgery centers participating in the Bozeman Epilepsy Consortium. RESULTS: Those patients who continued to have seizures following surgery had statistically lower preoperative IQ scores than those who were seizure-free (p < 0.009), but only by 2.3 points. This small but statistically significant relationship was fairly robust; it was observed across seven of the eight centers, and indicates that the findings can be generalized. Among patients with IQ scores of < or = 75, 32.8% continued to have seizures following surgery, whereas 23.8% and 16.9% were not seizure-free when IQ scores were between 76 and 109 and > or = 110, respectively. Relative risk analyses revealed no significant increase in risk among patients with low IQ scores who had no structural lesions other than mesial temporal sclerosis. However, patients with IQ scores of < or = 75 had nearly a fourfold (390%) increase in risk for continued seizures as compared with those with higher IQ scores if structural lesions were present. CONCLUSIONS: While our results suggest that preoperative IQ scores alone are not good predictors of seizure outcome and should not be used to exclude patients as potential surgical candidates. IQ scores can be useful for counseling patients and their families concerning the relative risks of surgery.

Comorbidity↗
PubMed1997

Differential rates of age of seizure onset between sexes and between hemispheres?

In a descriptive analysis of 158 patients with temporal lobe epilepsy, Taylor (1969) reported that the age of first seizure varied systematically as a function of laterality and sex. We conducted inferential analyses of Taylor's original data which (1) provided support for his proposal of disproportionate left hemisphere vulnerability to seizure onset in early life, but (2) failed to provide evidence of sex differences in age of onset of unilateral seizures. Examination of these effects in a larger sample of 844 patients drawn from the Bozeman Epilepsy Consortium provided some additional support for findings from the inferential analysis. Specifically, the left hemisphere appeared more vulnerable to seizure onset in childhood, this increased vulnerability extending to about age 5 years. Age of onset of seizures was not different when males and females were compared. Thus, reanalysis of Taylor's original data as well as examination of data from a larger, more contemporary sample suggest that seizure onset varies as a function of laterality, but not sex.

Adult↗
PubMed1997

The use of figural reproduction tests as measures of nonverbal memory in epilepsy surgery candidates.

The construct of nonverbal memory, as assessed by figural reproduction tests, has recently been questioned by a number of investigators. The purpose of this study was to reexamine this construct and its relationship to right temporal lobe dysfunction. Figural reproduction test scores were examined in 757 epilepsy surgery candidates obtained from 8 epilepsy centers participating in the Bozeman Epilepsy Consortium. All participants exhibited unequivocal evidence of left (LTL) or right (RTL) temporal lobe epilepsy observed in ictal and interictal EEG recordings. All subjects also had IQ scores exceeding 70, right-hand preference, and left hemisphere language dominance confirmed by intracarotid sodium amytal testing. Comparisons of LTL and RTL groups showed no significant differences in scores on the Visual Reproduction subtests from the Wechsler Memory Scale (WMS) or Wechsler Memory Scale-Revised (WMS-R) or on the copy and delayed recall conditions of the Rey-Osterrieth Complex Figure Test (ROCFT). Significant differences were observed among centers on WMS and ROCFT scores, which are likely to be a result of variations in administration and/or scoring procedures. The lack of significant differences between LTL and RTL groups in this large sample raise questions about the nature of nonverbal memory and its relationship to right temporal lobe dysfunction.

Adult↗
PubMed1996

Neurodevelopmental outcome at 36 months' corrected age of preterm infants in the Multicenter Indomethacin Intraventricular Hemorrhage Prevention Trial.

OBJECTIVES: Low-dose indomethacin has been shown to prevent intraventricular hemorrhage (IVH) in very low birth weight neonates, and long-term neurodevelopmental follow-up data are needed to validate this intervention. We hypothesized that the early administration of low-dose indomethacin would not be associated with adverse cognitive outcome at 36 months' corrected age (CA). METHODS: We enrolled 431 neonates of 600 to 1250 g birth weight with no IVH at 6 to 12 hours in a randomized, prospective trial to determine whether low-dose indomethacin would prevent IVH. A priori, neurodevelopmental follow-up examinations, including the Stanford-Binet Intelligence Scale and Peabody Picture Vocabulary Test-Revised, and standard neurologic examinations were planned at 36 months' CA. RESULTS: Three hundred eighty-four of the 431 infants survived (192 [92%] of 209 infants receiving indomethacin versus 192 [86%] of 222 infants receiving saline), and 343 (89%) children were examined at 36 months' CA. Thirteen (8%) of the 166 infants who received indomethacin and 14 (8%) of 167 infants receiving the placebo were found to have cerebral palsy. There were no differences in the incidence of deafness or blindness between the two groups. For the 248 English-monolingual children for whom IQ data follow, the mean gestational age was significantly younger for the infants who received indomethacin than for those who received the placebo. None of the 115 infants who received indomethacin was found to have ventriculomegaly on cranial ultrasound at term, compared with 5 of 110 infants who received the placebo. The mean +/- SD Stanford-Binet IQ score for the 126 English-monolingual children who had received indomethacin was 89.6 +/- 18.92, compared with 85.0 +/- 20.79 for the 122 English-monolingual children who had received the placebo. Although maternal education was strongly correlated with Stanford-Binet IQ at 36 months' CA, there was no difference in educational levels between mothers of the infants receiving indomethacin and the placebo. CONCLUSIONS: Indomethacin administered at 6 to 12 hours as prophylaxis against IVH in very low birth weight infants does not result in adverse cognitive or motor outcomes at 36 months' CA.

Cerebral Hemorrhage↗
PubMed1995

General cognitive ability following unilateral and bilateral fetal ventral mesencephalic tissue transplantation for treatment of Parkinson's disease.

OBJECTIVE: To contrast the neuropsychological profiles of Parkinsonian patients, before and after fetal ventral mesencephalic tissue transplantation. DESIGN: Case series of personally examined patients. SETTING: Patients were evaluated by neurologists, neurosurgeons, and neuropsychologists as outpatients at a university hospital. PATIENTS: Fetal mesencephalic tissue was implanted in the right caudate nucleus of three patients and both nuclei of one patient. These patients were evaluated prior to surgery and at 12, 24, and 26 months postoperatively. RESULTS: Factor analysis of the test battery identified four statistically orthogonal test clusters. No statistically significant changes were identified postoperatively for clusters assessing verbal cognitive ability, nonverbal cognitive ability, and information-processing speed. An improvement of verbal memory cluster index was observed 12 months after surgery, and the improvement reached the level of statistical significance at 24 months after surgery. However, the verbal memory of all patients declined between 24 and 36 months after surgery. CONCLUSIONS: Fetal tissue transplantation to one or both caudate nuclei did not permanently arrest cognitive dysfunction. Although there is some evidence of improved cognitive ability after transplantation, it is improbable that normal cognitive function can be restored by this procedure because the impairments of cognitive ability associated with Parkinson's disease do not appear to originate solely from dopamine deficiency.

Adult↗
PubMed1995

MRI hippocampal volume and neuropsychology in epilepsy surgery.

A review is provided of recent findings on relationships between neurocognitive test data and magnetic resonance imaging (MRI)-determined hippocampal volumes in nonlesional temporal lobectomy patients. The difference between the right and left hippocampal volumes is correlated with postoperative verbal memory in left temporal lobectomy patients who do not have lesional pathology. MRI hippocampal volume data are not associated with measures of executive functioning or naming. Sex differences have been found for verbal memory outcome as women have better verbal memory following left temporal lobectomy. Sex differences have also been found in the relationships between verbal and visual memory, and hippocampal volume data. The systematic combination of MRI-acquired morphological data and neuropsychological test data may further our understanding of neurocognitive function, and provide clinically useful data for counseling epilepsy surgery patients. The current data are promising with regard to prediction of memory outcome following temporal lobectomy, but they do not yet allow for prediction of specific individual patient outcomes. Rather, the currently available data support counseling patients based on the memory outcome of others with similar characteristics.

Dominance, Cerebral↗