Identification of genetically mediated cortical networks: a multivariate study of pediatric twins and siblings.

Structural magnetic resonance imaging data from 308 twins, 64 singleton siblings of twins, and 228 singletons were analyzed using structural equation modeling and selected multivariate methods to identify genetically mediated intracortical associations. Principal components analyses (PCA) of the genetic correlation matrix indicated a single factor accounting for over 60% of the genetic variability in cortical thickness. When covaried for mean global cortical thickness, PCA, cluster analyses, and graph models identified genetically mediated fronto-parietal and occipital networks. Graph theoretical models suggest that the observed genetically mediated relationships follow small world architectural rules. These findings are largely concordant with other multivariate studies of brain structure and function, the twin literature, and current understanding on the role of genes in cortical neurodevelopment.

Neurological impairment among elderly African-American nursing home residents.

In this pilot study, 288 elderly African-American and 482 white residents of 10 nursing homes in Wayne County, Michigan, were compared for neurological impairment. The frequency of diagnosis of neurological impairment was equivalent for African-American and white males, but greater for African-American females than for white females. Cerebral vascular accident (CVA, or stroke) and nonspecific dementia were the most common neurological diagnoses for all groups. For males but not females, there was a statistically significant difference in the causes of neurological impairment, with more African-Americans diagnosed as having CVA, and more whites diagnosed as having nonspecific dementia. While the incidence of neurological impairment in African-Americans exceeded that of whites, predominantly white nursing homes offered more sophisticated care. This suggests the need to review the means by which comprehensive nursing home care may be expanded in the African-American community.

Assessment of oral peripheral structure and function in normal aging individuals with the Frenchay.

This research was designed to investigate the integrity of oral motor structure and function in normal aging individuals using the Frenchay Dysarthria Assessment (FDA). Subjects were 5 females and 5 males in each of 4 age categories (50-59, 60-69, 70-79, and 80-89). Two individuals, trained in the use of the FDA, administered this procedure to the 40 subjects. Test-retest reliability measures (done one week apart) for eight of the subjects revealed no change from time 1 to time 2. Minimal reduced functioning for some FDA tasks, particularly the Laryngeal Subtest and the Tongue Subtest, were noted with increasing age.

Comprehension of neutral, melodically intoned, and affectively toned sentences by adults with aphasia.

The purpose of this study was to investigate whether there is a notable improvement in the auditory comprehension of adults with aphasia when sentences are melodically intoned or spoken with strong affect, as compared to when the same sentence materials are spoken in a neutral manner. The subjects for this study were six aphasic patients with left-brain damage and two control subjects: one patient with bilateral brain damage and one subject with no history of neurological insult. The subjects responded to a picture identification task where the same sentence stimuli were presented in three conditions: neutral, melodic intonation, and strong affect. There was no significant difference in the left-brain damaged patients' auditory comprehension scores in the three conditions. No improvement of performance was noted for the bilaterally brain-damaged patient, and the nonaphasic subject attained a perfect or near-perfect score in each condition. Results are discussed in terms of the need for future research.

Stroke and traumatic brain injury (ma'i ulu) in Amerika Samoa.

This paper discusses the annual incidence of stroke and traumatic brain injury (TBI) in American Samoa. Findings are based on data collected from the medical records at LBJ Tropical Medical Center in Amerika Samoa from June 1, 1989 to May 31, 1990. A review of these medical records revealed that stroke and TBI were prevalent among the residents of Amerika Samoa during the time period sampled. Health and cultural factors which contribute to the occurrence of stroke and TBI in Amerika Samoa and recommendations for further investigation and prevention of stroke and TBI in that country are discussed.

A case-control study of brain structure and behavioral characteristics in 47,XXX syndrome.

Trisomy X, the presence of an extra X chromosome in females (47,XXX), is a relatively common but under-recognized chromosomal disorder associated with characteristic cognitive and behavioral features of varying severity. The objective of this study was to determine whether there were neuroanatomical differences in girls with Trisomy X that could relate to cognitive and behavioral differences characteristic of the disorder during childhood and adolescence. MRI scans were obtained on 35 girls with Trisomy X (mean age 11.4, SD 5.5) and 70 age- and sex-matched healthy controls. Cognitive and behavioral testing was also performed. Trisomy X girls underwent a semi-structured psychiatric interview. Regional brain volumes and cortical thickness were compared between the two groups. Total brain volume was significantly decreased in subjects with Trisomy X, as were all regional volumes with the exception of parietal gray matter. Differences in cortical thickness had a mixed pattern. The subjects with Trisomy X had thicker cortex in bilateral medial prefrontal cortex and right medial temporal lobe, but decreased cortical thickness in both lateral temporal lobes. The most common psychiatric disorders present in this sample of Trisomy X girls included anxiety disorders (40%), attention-deficit disorder (17%) and depressive disorders (11%). The most strongly affected brain regions are consistent with phenotypic characteristics such as language delay, poor executive function and heightened anxiety previously described in population-based studies of Trisomy X and also found in our sample.

Are there differences in brain morphometry between twins and unrelated singletons? A pediatric MRI study.

Twins provide a unique capacity to explore relative genetic and environmental contributions to brain development, but results are applicable to non-twin populations only to the extent that twin and singleton brains are alike. A reason to suspect differences is that as a group twins are more likely than singletons to experience adverse prenatal and perinatal events that may affect brain development. We sought to assess whether this increased risk leads to differences in child or adolescent brain anatomy in twins who do not experience behavioral or neurological sequelae during the perinatal period. Brain MRI scans of 185 healthy pediatric twins (mean age = 11.0, SD = 3.6) were compared to scans of 167 age- and sex-matched unrelated singletons on brain structures measured, which included gray and white matter lobar volumes, ventricular volume, and area of the corpus callosum. There were no significant differences between groups for any structure, despite sufficient power for low type II (i.e. false negative) error. The implications of these results are twofold: (1) within this age range and for these measures, it is appropriate to include healthy twins in studies of typical brain development, and (2) findings regarding heritability of brain structures obtained from twin studies can be generalized to non-twin populations.

An inclusive management approach for individuals with right hemisphere deficits.

Diversity, multiculturalism, and individual differences are concepts that are becoming of greater interest to speech-language pathologists as they strive to make clinical management more functional and meaningful for all clients. This article discusses a new way of viewing these concepts and suggests how to weave them into the framework of clinical management. Specific attention to those aspects of performance likely to be influenced by culture, communication style, and individual differences among people with right hemisphere impairments are discussed. In addition, ways in which this information can be used to enhance the assessment and treatment of these individuals are suggested.

Cognitive-linguistic assessment of individuals with multiple sclerosis.

Four individuals diagnosed as having multiple sclerosis (MS) and four matched controls were assessed with the Arizona Battery for Communication Disorders (ABCD), a standardized battery of memory and cognitive-linguistic tasks. Subjects with MS and controls performed in an equivalent or nearly equivalent fashion for nine of the ABCD subtests. For five of the subtests (Object Description, Generative Naming, Concept Definition, Generative Writing, and Picture Description), subjects with MS performed substantially lower than the control subjects. Results of this pilot study suggest that portions of the ABCD may be useful in identifying profiles of memory, and cognitive-linguistic impairment among individuals with multiple sclerosis. Further research using a larger sampling of individuals with MS is needed to more fully assess the usefulness of the ABCD with this population.

Effects of personally relevant language materials on the performance of severely aphasic individuals.

The purpose of this study was to determine whether or not severely aphasic adults perform better with personally relevant language materials than with otherwise similar nonpersonal language materials. The subjects for this study were 24 severely aphasic individuals. Subjects responded to personally relevant and nonpersonal materials in four language tasks: auditory comprehension, speech repetition, naming, and reading comprehension. Subjects showed significantly better performance on personally relevant items than on nonpersonal items. This was true for each of the four tasks.

Analysis of auditory comprehension performance in individuals with severe aphasia.

This research compared the performance of 20 individuals with global and mixed nonfluent aphasia across the four auditory comprehension subtests of the Boston Diagnostic Aphasia Examination (Word Discrimination, Body Part Identification, Commands, and Complex Ideational Material) and across the six subcomponents of the Word Discrimination Subtest (objects, actions, letters, colors, forms, and numbers). As expected, group means revealed severely reduced performance which was equally observable across all auditory comprehension tasks. To determine whether individual subjects demonstrated a pattern of consistently reduced performance for auditory comprehension tasks, z-scores and chi-square statistics were also calculated for each subject and task. The individuals with global aphasia demonstrated a greater number of statistically significant z-scores than was expected by chance. This was not true for the subjects with mixed nonfluent aphasia. Results of this research indicate that although as a group individuals with global aphasia may demonstrate consistently reduced auditory comprehension, when considered on an individual basis, this group may comprise a somewhat divergent population with respect to the configuration of preserved and impaired auditory comprehension skills.

Change in psychosocial functioning and social relations among women in residential substance abuse treatment.

PURPOSE: The purpose of this study was to examine the degree to which psychosocial functioning and social relationships changed during the first 3 months of treatment among women in a residential substance abuse program that emphasizes the importance of developing healthy relationships. METHODS: Participants included 77 female clients admitted to the Salvation Army First Choice (FC) Program in Fort Worth, TX. Assessments of psychological functioning, family relations, and peer relations were administered at treatment entry and again after 3 months. Relationships with clients in treatment and friends outside treatment were measured separately. RESULTS: Repeated-measures analyses of variance (ANOVA) indicated that interpersonal relationships improved. Family networks increased, family cohesion increased, and family conflict decreased. Peer networks changed as well, due in part to new relationships with other clients in treatment. The number of drug-using friends decreased, peer deviance and negative influence decreased, and social conformity among friends increased. There was a corresponding improvement in psychosocial functioning. IMPLICATIONS: Results suggested that relationship-centered treatment for women was effective. Clients reestablished connections with family members, disassociated from drug-using peers, and improved the quality of relationships with family members and friends. Further research is needed in order to examine the influence of specific treatment components and the potential long-term effects of changes in women's relationships.