Search

The purpose of the study was to examine the link between geographic information system (GIS)-estimated regional specific groundwater levels and neuropsychological functioning in a sample of individuals with and without cognitive impairment.This cross-sectional study design analyzed data from 1390 participants (733 Alzheimer's disease, 127 Mild Cognitive Impairment, and 530 with normal cognition) enrolled in the Texas Alzheimer's Research and Care Consortium. GISs analyses were used to estimate regional specific groundwater arsenic concentrations using the Environmental Systems Research Institute and arsenic concentrations from the Texas Water Development Board.In the full cohort, regional specific arsenic concentrations were positively associated with language abilities (p = 0.008), but associated with poorer verbal memory, immediate (p = 0.008), and delayed (p 0.001), as well as poorer visual memory, immediate (p = 0.02), and delayed (p 0.001). The findings varied by diagnostic category with arsenic being related with cognition most prominently among mild cognitive impairment cases.Overall, estimated regional specific groundwater arsenic levels were negatively associated with neuropsychological performance.

The Brief Smell Identification Test (BSIT) is a commonly used measure of olfactory functioning in elderly populations. Few studies have provided normative data for this measure, and minimal data are available regarding the impact of sociodemographic factors on test scores. This study presents normative data for the BSIT in a sample of English- and Spanish-speaking Hispanic and non-Hispanic Whites. A Rasch analysis was also conducted to identify the items that best discriminated between varying levels of olfactory functioning, as measured by the BSIT. The total sample included 302 older adults seen as part of an ongoing study of rural cognitive aging, Project FRONTIER. Hierarchical regression analyses revealed that BSIT scores require adjustment by age and gender, but years of education, ethnicity, and language did not significantly influence BSIT performance. Four items best discriminated between varying levels of smell identification, accounting for 59.44% of total information provided by the measure. However, items did not represent a continuum of difficulty on the BSIT. The results of this study indicate that the BSIT appears to be well-suited for assessing odor identification deficits in older adults of diverse backgrounds, but that fine-tuning of this instrument may be recommended in light of its items' difficulty and discrimination parameters. Clinical and empirical implications are discussed.

The importance of the detection of possible symptom exaggeration/malingering has gained increased attention among neuropsychologists, and as a result, a number of techniques have been developed for the identification of suspected malingering. The goal of this study was to examine the extent towhich several of these commonly used techniques correlate with one another in a clinical sample. Archival data on 97 litigants were analyzed, and scores on the Test of Memory Malingering (TOMM), Rey 15-Item Test (Rey-15), and MMPI-2 validity scales were compared. The MMPI-2 validity scales did not positively correlate with any trial on the TOMM or with the Rey-15, with the exception of the Fb scale which significantly negatively correlated with TOMM trial 1. The results of the present study suggest that the MMPI-2 validity scales are measuring a different construct than tests of malingered memory deficits, and therefore should be interpreted cautiously in forensic evaluations.

The Trail Making Test (TMT) is one of the most commonly administered tests in neuropsychological assessments. It has been shown to be a valid indicator of brain damage due to traumatic brain injury (TBI), as well as a number of other neuropathological conditions. TMT error and ratio scores have been suggested as possible markers of malingering. The present study examined the utility of various TMT scores as malingering measures in 94 TBI litigants. Litigants were divided into those suspected of (n = 27) and those not suspected of malingering (n = 67) based on scores obtained on the Test of Memory Malingering and/or the Rey 15-Item Test. TMT errors did not discriminate between suspected and nonsuspected malingerers; however, the overall level of performance on the TMT was suppressed in suspected malingerers. The TMT ratio score was significantly lower in litigants suspected of malingering, although the clinical utility of this ratio is minimal. Results of the present study suggest using caution when interpreting TMT scores as markers of malingering in TBI litigants.