Measuring cognition in advanced Alzheimer's disease for clinical trials.

Measurement of cognitive dysfunction and treatment response in the early stages of Alzheimer's disease (AD) has used such scales as the Mini-Mental State Examination (MMSE) and the AD Assessment Scale (ADAS). With the exception of clinical rating scales, however, there are only a few objective measures of cognition for tracking progression in advanced AD. Given renewed interest in potential therapies for advanced AD, objective measures of cognition are important for the adequate evaluation of change due to AD progression or therapy. Several cognitive measures for advanced AD are reviewed. One measure, the Severe Impairment Battery (SIB) is reviewed in detail. Preliminary analyses from a trial of memantine show significant change on the SIB in memory (p < 0.001) and visuospatial functions (p < 0.02) over six-months with a trend for language and praxis. Data from a donepezil trial also highlight the importance of accurate assessment in advanced AD.

The effects of two motivational manipulations on the neuropsychological performance of mildly head-injured college students.

Recently, much research has focused on the development and utilization of various motivational assessment techniques designed to identify malingered neuropsychological test performance. Other findings have suggested a strong link between the motivation of the subject and the degree to which the neuropsychological test results validly represent the individual's true level of functioning. However, the majority of the empirical work in this area has focused on only one end of the motivational spectrum, decreased motivation. In order to obtain a more complete assessment of the relationship between motivation and neuropsychological of test results, the present study involved an evaluation of the effects of motivational differences on test performance across three levels of motivation: high, low, and standard in 75 head-injured college students. Results supported past research showing significant decreases in test performance by participants given individual financial incentives (25.00 US dollars) to perform poorly. Additionally, the sensitivity of several malingering tests to this response set was supported. However, no reliable differences were found on neuropsychological or motivational tests between the group given financial incentives (25.00 US dollars) to perform well and the standard instruction group.