Biomedical subjects

Bruce P Hermann

Publications and source records attributed to Bruce P Hermann.

5 recordsLinked to original sources

PubMed2003

Confirmatory factor analysis of the WMS-III in patients with temporal lobe epilepsy.

Five competing models specifying the factor structure underlying the Wechsler Memory Scale-Third Edition (D. Wechsler, 1997b) primary subtest scores were evaluated in a sample of patients with intractable temporal lobe epilepsy (N = 254). Models specifying separate immediate and delayed constructs resulted in inadmissible parameter estimates and model specification error. There were negligible goodness-of-fit differences between a 3-factor model of working memory, auditory memory, and visual memory and a nested--more parsimonious--2-factor model of working memory and general memory. The results suggest that specifying a separate visual memory factor provides little advantage for this sample--an unexpected finding in a population with lateralized dysfunction, for which one might have predicted separate auditory and visual memory dimensions.

Adult↗

PubMed2002

The neurodevelopmental impact of childhood onset temporal lobe epilepsy on brain structure and function and the risk of progressive cognitive effects.

The purpose of this study is to explore the possibility of progressive neuropsychological decline in chronic temporal lobe epilepsy (TLE) and determine how this vulnerability may be associated with the neurodevelopmental impact of the disorder. 53 patients with TLE and 62 healthy controls underwent quantitative MRI volumetric imaging of total brain tissue and hippocampal volumes as well as assessment of intelligence and memory function. In addition to reduced hippocampal volume, childhood onset (< 14 years) but not adult onset TLE was associated with significantly reduced total brain tissue that was generalized in nature and extended into extratemporal regions. In addition to this adverse impact on brain structure, there was significantly reduced intellectual status as well as memory function in childhood onset TLE patients, consistent with the generalized nature of the MRI volumetric abnormalities. Finally, cross-sectional correlational analyses indicated that increasing duration of epilepsy in childhood onset patients was associated with declining performance across both intellectual and memory measures, suggestive of progressive cognitive effects. We propose that childhood onset TLE is associated with an adverse neurodevelopmental impact on brain structure and function which represents an early acquired vulnerability, effectively reducing cerebral reserve, placing patients at risk for progressive cognitive decline in the context of chronic and unremitting epilepsy.

Age of Onset↗

PubMed2002

Diffusion tensor MRI in temporal lobe epilepsy.

The purpose of this study was to investigate the diffusion characteristics of white matter in patients with focal temporal lobe epilepsy (TLE). Diffusion tensor imaging (DTI) was applied to patients and normal controls. Rotationally invariant mean diffusivity and diffusion anisotropy maps were calculated for all subjects. Comparisons between the two groups were performed for several white matter structures. Mean diffusivity and diffusion anisotropy of each selected structure were tested for correlations with age at onset and duration of epilepsy. Significantly lower diffusion anisotropy, and higher diffusivity in directions perpendicular to the axons, was detected in several white matter structures of the patients when compared to the controls. These structures were not located in the temporal lobes. No significant difference in mean diffusivity was detected between the selected structures from the two groups. Diffusion anisotropy was significantly correlated with age at onset of epilepsy in the posterior corpus callosum. Duration of epilepsy was not significantly correlated with the diffusion indices from any of the selected structures. The results of this study suggest that diffusion anisotropy may reveal abnormalities in patients with focal TLE. In addition, these abnormal changes are not necessarily restricted to the temporal lobes but might extend in other brain regions as well. Furthermore, the age at onset of epilepsy may be an important factor in determining the extent of the effect of epilepsy on white matter.

Adult↗

PubMed2002

Long-term psychosocial outcomes of anterior temporal lobectomy.

PURPOSE: To examine the long-term psychosocial outcomes of a consecutive series of patients who underwent anterior temporal lobectomy (ATL) compared with medically managed patients. This study focused primarily on actual long-term changes (mean, 5 years) in life performance. There are relatively few long-term controlled studies of actual lifetime performance changes. METHODS: The sample consisted of 61 adults who underwent ATL and 23 individuals who were evaluated for surgery but did not proceed to surgery and continued to receive medical management. Participants were interviewed 2-9 years after surgery. A structured clinical interview and review of medical records was conducted to obtain information regarding seizure frequency and psychosocial status, focusing on employment, education, driving status, financial assistance, and independent living. In addition, two questions regarding quality of life were included. Seizure frequency was evaluated for the year before the interview. RESULTS: Significant differences in psychosocial outcome were found between the surgery group and medical management group. Favorable psychosocial outcomes were more common among those who had surgery (46 vs. 4%). Results indicated that 68% of the surgery group exhibited improved psychosocial status compared with 5% of the medical management group. Individuals who had surgery were more likely to be driving, working full-time, living independently, and being financially independent. Remaining seizure free was not a prerequisite for improvements in psychosocial outcomes. CONCLUSIONS: Compared with medical management, surgery has a significant positive impact on psychosocial outcomes in terms of employment, independent living, driving, and financial independence. Additionally, a person does not necessarily have to be seizure free to achieve positive changes in psychosocial outcomes.

Activities of Daily Living↗

PubMedDate not supplied

Visual and auditory naming in patients with left or bilateral temporal lobe epilepsy.

Impairment on visual naming tests is relatively common among temporal lobe epilepsy (TLE) patients. Recent reports suggested that the ability to name objects on the basis of their descriptions is an even more sensitive and perhaps more ecologically valid measure of naming problems among left hemisphere TLE patients. To further explore the nature of dysnomia in TLE, the current study assessed a group of patients with either left or bilateral TLE (n=16) and a group of healthy controls (n=11) on computerized measures of naming to description or auditory naming (AN) and visual naming (VN). Both speed and accuracy scores on AN distinguished patients from controls better than VN scores. There was a trend for AN speed, but not other naming test variables, to be associated with self-reported word finding problems. AN speed and accuracy, but not VN scores, correlated significantly with a broad range of other cognitive test scores. In summary, AN speed and accuracy are sensitive indexes of cognitive dysfunction in TLE patients. AN may be an appropriate analogue of the word finding demands of conversational speech because of its multiple neuropsychological demands. These results provide further evidence of the potential value of AN assessment in TLE patients. Further study of the cognitive processes required during AN, its relation to word finding problems in discourse, and the effect of anterior temporal lobectomy on this ability is warranted.

Adult↗