Vascular risk factors affect cerebral blood flow (CBF) and cerebral vascular reactivity, contributing to cognitive decline. Hippocampus is vulnerable to both Alzheimer's disease (AD) pathology and ischemia; nonetheless, the information about the impact of vascular risk on hippocampal perfusion is minimal. Cognitively, healthy elderly (NL18, 69.96.7 years) and subjects with mild cognitive impairment (MCI15, 74.98.1 years) were evaluated for the Framingham cardiovascular risk profile (FCRP). All underwent structural imaging and resting CBF assessment with arterial spin labeling (ASL) at 3T magnetic resonance imaging (MRI). In 24 subjects (NL17, MCI7), CBF was measured after a carbon dioxide rebreathing challenge. Across all subjects, FCRP negatively correlated with hippocampal (0.41, P0.049) and global cortical (0.46, P0.02) vasoreactivity to hypercapnia (VRh). The FCRP-VRh relationships were most pronounced in the MCI group: hippocampus (0.77, P=0.04); global cortex (0.83, P=0.02). The FCRP did not correlate with either volume or resting CBF. The hippocampal VR h was lower in MCI than in NL subjects (Z2.0, P=0.047). This difference persisted after age and FCRP correction (F 3,20 4.6, P0.05). An elevated risk for vascular pathology is associated with a reduced response to hypercapnia in both hippocampal and cortical tissue. The VR h is more sensitive to vascular burden than either resting CBF or brain volume.

Objective: To examine the associations of suicide in the second half of life with medical and psychiatric illness, functional limitations, and reported use of inpatient, ambulatory, and home health care services. Method:A retrospective case-control design was used to compare 86 people over age 50 years who died by suicide with a comparison group of 86 living community participants that were individually matched on age, gender, race, and county of residence. Results: Suicide decedents had more Axis I diagnoses, including current mood and anxiety disorders, worse physical health status, and greater impairment in functional capacity. They were more likely to have required psychiatric treatment, medical, or surgical hospitalization in the last year, and visiting nurse or home health aide services. In a multivariate model, the presence of any active Axis I disorder and any impairment in instrumental activities of daily living (IADL) made independent contributions to suicide risk. Conclusions: Mental illness, physical illness, and associated functional impairments represent domains of risk for suicide in this age group. In addition to individuals with psychiatric illness, those with severe or comorbid physical illness and functional disability who require inpatient and home care services should be targeted for screening and preventive interventions.

No description available.

The purpose of this study was to examine differences in early intervention (EI) referral and service frequency for children with blindness or visual impairment (BVI) and gather information about the practices and experiences of vision professionals across the United States. The study focused on obtaining data from certified teachers of students with visual impairment (CTVI) and certified orientation and mobility specialists (COMS) in the United States. Information collected included descriptive statistics and professional information about EI for children with BVI, and information about the referral process and service frequency for children with BVI during EI. Thirty-three states were represented in the collected data. Of these states, 26 had responses from four or more professionals, the criteria for inclusion in the analyses. Participants provided information based on a researcher-developed survey requesting information related to the procedures used to provide EI services for children with BVI. Questions were adapted from established instruments where possible. Across states, there were some statistically significant differences in CTVIs and COMS reports of procedures regarding the role of professional collaboration, parent/caregiver participation in IFSP meetings, strengths/resources utilized by vision professionals, and challenges parents/families encountered when accessing EI services for their child with BVI. No statistically significant differences were identified across states for type of referral method, most commonly initiated by health care professionals, or method by which service frequency was determined. Results will be used to inform future research to further examine EI for children with BVI in the United States.

Background: Currently, the majority of learners within the South African education system speak English as an additional language. Many of these children are therefore learning the language of instruction through the language of instruction. Of particular concern for speech-language therapists (SLTs) are those children who have language impairment. In addition, it is important for SLTs to be able to distinguish between the learners who have language impairment, and those who are merely in the process of acquiring English. Additionally, the identification of language impairment among learners who speak English as an additional language is difficult as there are no overt manifestations of language learning difficulties, and, unfortunately, these learners are easily over-looked during the pre-school and school-age years. Furthermore, specifically within the South African context, there are limited tools available that can be used to screen for, and/or diagnose language impairment among EAL learners. Purpose: The main aim of this study was to explore the use of sentence repetition as a screening tool for the identification of language impairment in learners who speak English as an additional language. Method: The research design of this study was non-experimental, quantitative, descriptive and cross-sectional in nature, with comparative and correlational components. One hundred and seven grade 2 EAL learners from a mainstream school in Gauteng participated in the study. The learners were evaluated on two sentence repetition tests; the Redmond (2005) Sentence Repetition Test and the Recalling Sentences subtest from the Clinical Evaluation of Language Fundamentals-4 (CELF-4) (Semel, Wiig & Secord, 2003). The learners were also evaluated on the Gray Oral Reading Test-4 (GORT-4) (Wiederholt & Bryant, 2001). The results obtained from these measures were correlated in order to determine the internal validity of the two sentence repetition measures, as well as to investigate the extent to which sentence repetition can be used to predict academic literacy. Learners who were identified as being at-risk for language impairment, namely those who fell 1 standard deviation (SD) below the peer group mean on the Redmond (2005) Sentence Repetition test were further evaluated using the Diagnostic Evaluation of Language Variation-Criterion Referenced edition (DELV-CR) (Seymour, Roeper & de Villiers, 2003), to diagnose language impairment, avoid misdiagnosis, and describe the manifestations of language impairment in the second language. Results and Implications: The results of the Redmond (2005) Sentence Repetition test proved to be a valid measure to identify learners who were at-risk for language impairment, provided that the peer group mean was used as a standard of comparison. Twelve of the 107 (11.2%) learners from the study were identified as being at-risk for language impairment. However, after analysis of the results and using a peer group mean from Jordaan’s (2011) study, only 9/12 (7.5%) of the participants were diagnosed with language impairment. This finding highlights the fact that EAL learners are often over-identified as having language impairment and further assessment is necessary to minimise the risk of misdiagnosis of language impairment. The findings from the DELV-CR (Seymour, Roeper & de Villiers, v 2003), in terms of the manifestations of language impairment in the second language, were consistent with the EAL language impaired learners from Jordaan’s (2011) study, as well as the literature. This finding indicates that sentence repetition is a valid screening tool for the identification of language impairment in EAL learners. Furthermore, 11 of the 12 of the at-risk learners scored below the peer group mean on the reading comprehension measure. Thus, it is evident that, in addition to not being able to use language effectively for academic purposes, most children with language impairment are further disadvantaged by poor reading comprehension skills. An implication for future research would be to explore whether the development of a sentence repetition measure in an African language (e.g. Zulu) would yield similar results as the current study. In this way, EAL learners could be identified in their home language. A secondary finding of the current study was that the grade 2 educators were not able to identify learners who required additional language support within the classroom. This finding has implications for the role of SLTs in mainstream education and the need to support educators in their ability to identify learners with SLI and whose academic language development is not on par with that of their peers.

The purpose of the study was to investigate the prevalence and effects of vision impairment co-existing with other comorbid conditions. Utilizing the 2008 National Health Interview Survey, the most recent nationally representative data including expanded vision, health conditions, and activity questions, this study examined the effect of vision impairment co-existing with selected comorbid conditions among non-institutionalized older adults age ≥ 55 years. Specifically, this study compared 4 groups: (a) older adults with neither vison impairment nor comorbid conditions, (b) older adults with vision impairment only, (c) older adults with comorbid conditions only, and (d) older adults with both vision impairment and each of the comorbid conditions to examine the prevalence and effect of vision impairment and comorbid conditions on selected mobility and vision activity limitations, and participation restrictions. Using complex sample techniques to conduct frequency analyses and logistic regression procedures, this study compared these groups of older adults to document the likelihood of experiencing mobility and vision activity limitations, and participatory restrictions. These results suggest that older adults reporting vision impairments are a heterogeneous population, overwhelmingly use corrective lenses, and experience substantial mobility and vision activity limitations, and participatory restrictions; however, relatively few report using low vision aids or rehabilitation services. In addition, these results revealed, even when controlling for age, sex, race/ethnicity, marital status, region of residence, and health status, older adults with vision impairment and any of the selected comorbid conditions were statistically significantly more likely to report mobility and vision activity limitations, and participation restrictions. Moreover, when comparing older adults reporting vision impairment co-existing with comorbid conditions older adults reporting either vision impairment only or a comorbid condition only, the results suggest vision impairment had the largest statistically significant effect on the likelihood of mobility or vision activity limitations, or participatory restriction in 29 of the 44 logistic regression analyses. These findings are significant as vision impairment is framed as a public health concern, and can inform improvements in programs and services for older adults. Finally, these findings highlight the need for expanded research examining the effect of specific eye diseases and comorbid conditions among older adults.

Immigrants are an important part of Canada and Canadian culture. Despite a large number of immigrants in Canada relatively few studies have focused on disability and immigrants. Even less research has been conducted on immigrants with visual impairments. The first paper uses the Participation Activity Limitation Survey (PALS) from 2006 to examine the prevalence of vision impairment in immigrants compared to non-immigrants, 50 years of age and over. First, descriptive statistics were used to determine the prevalence rate of vision impairment. Then, multivariate logistic regression was utilized to examine differences in providers of support and characteristics of individuals who receive support. Results disclosed that there was no difference in the prevalence rates of adult immigrants and non-immigrants over 50 years of age when controlling for age and gender. Results confirmed that there is a relationship between having a vision impairment and living in a low income household. Results also showed that receiving support is linked to severity of impairment. The second paper used qualitative analysis to examine visually impaired immigrants’ perception of vision impairment and disability and if perception influenced utilization of care. Qualitative semi-structured interviews were conducted with 8 clients of the Canadian National Institute for the Blind (CNIB). Results showed that immigrants’ employ three different views when explaining their impairment, these were; the medical view, social view and theological/ traditional view. All participants used two or more views interchangeably demonstrating that all views are important in understanding how immigrants perceive and navigate their impairment on an everyday basis. Results also suggested that negative perceptions did not keep most immigrants from accessing services; however, traditional barriers such as not being eligible to receive services and transportation were main barriers. / Thesis / Master of Arts (MA)

Compromised validity of test data due to exaggeration or fabrication of cognitive deficits inhibits the capacity to establish appropriate conclusions and recommendations in neuropsychological examinations. Detection of feigned neurocognitive impairment presents a formidable challenge, particularly for evaluations involving possibilities of significant secondary gain. Among specific populations examined in this domain, litigating mild traumatic brain injury (mTBI) samples are among the most researched. One subpopulation with potential to contribute significantly to this body of literature is that of retired athletes undergoing fixed-battery neuropsychological evaluations within an assessment program. Given the considerable prevalence of concussions sustained by athletes in this sport and the substantial monetary incentives within this program, a unique opportunity exists to establish rates of feigning within this population to be compared to similar forensic mTBI samples. Further, a fixed battery with multiple validity tests (VT) offers a chance to evaluate the classification accuracy of an aggregated VT failure paradigm, as uncertainty abounds regarding the optimal approach to the recommended use of multiple VTs for effort assessment. The current study seeks to examine rates of feigned neurocognitive impairment in this population, demonstrate prediction accuracy equivalence between models based on aggregated VT failures and logistic regression, and compare classification performance of various individual VTs.

Alzheimer's Disease (AD) is a neurodegenerative disease that causes complications with thinking capability, memory and behavior. AD is a major public health problem among the elderly in developed and developing countries. With the growth of AD around the world, there is a need to further expand our understanding of the roles different clinical measurements can have in the diagnosis of AD. In this work, we propose a machine learning-based technique to distinguish control subjects with no cognitive impairments, AD subjects, and subjects with mild cognitive impairment (MCI), often seen as precursors of AD. We utilized several machine learning (ML) techniques and found that Gradient Boosting Decision Trees achieved the highest performance above 84% classification accuracy. Also, we determined the importance of the features (clinical biomarkers) contributing to the proposed multi-class classification system. Further investigation on the biomarkers will pave the way to introduce better treatment plan for AD patients.

No description available.