Four new 15-item versions of the Boston Naming Test (BNT), a 15-item version used by the Consortium To Establish a Registry for Alzheimer's Disease (CERAD), and three 30-item BNT versions were studied in 26 subjects with Alzheimer's disease (AD) and 26 nondemented, neurologically normal controls. The four 15-item versions were statistically equivalent. On each version, controls performed significantly better than AD subjects, and scores on each could be extrapolated to a complete 60-item BNT score. The CERAD version also differentiated between AD and control subjects, but it was not equivalent to our four versions and could not be as easily extrapolated to a 60-item score. Even and Odd 30-item BNT versions were confirmed to be equivalent, and we further validated a 30-item Empirical Version designed to maximally discriminate between AD and normal subjects. Equivalent 15- or 30-item versions of the BNT will be useful in repeated assessments requiring independent forms of a naming task, as well as in situations where administration of the complete BNT is not practical.

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Patients with Alzheimer's disease (AD) (n = 36) and normal older adults (n = 36) were individually administered the Stroop Color-Word Test. Eight of 36 (22%) AD patients exhibited confusion between the colors blue and green, while no control subject had difficulty distinguishing among the colors. In a second experiment, a subset of the original sample (15 AD patients and 8 control subjects) was retested using the Stroop. Only 2 AD patients showed color confusion on both test occasions, while 7 AD patients exhibited color confusion on one occasion. No control subject exhibited confusion between colors the second time. These results indicate that color confusion in AD patients is inconsistent. Due to the high incidence of color confusion in AD patients, the Stroop should be used with caution in patient populations.

Despite the many functions attributed to the frontal-lobe in previous writings and studies, empirically derived and reliable frontal-lobe abilities are limited and specific. Research that examines frontal-lobe dysfunction (as evidenced by neuropsychological tests that measure these specific abilities) and its relationship to antisocial behavior is reviewed. Frontal-lobe dysfunction is discussed in the context of the "minimal brain dysfunction" hypothesis of criminal behavior. Three studies reviewed examine criminal behavior, three examine specifically violent criminal behavior, and three focus on psychopathy. The nature of the research reviewed leaves the relationship between frontal-lobe neuropsychological dysfunction and crime open to further study.

An extension to the basic lattice-BGK algorithm is presented for modeling a simulation region as a porous medium. The method recovers flow through a resistance field with arbitrary values of the resistance tensor components. Corrections to a previous algorithm are identified. Simple validation tests are performed which verify the accuracy of the method, and demonstrate that inertial effects give a deviation from Darcy's law for nominal simulation velocities.

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Numerical simulations are performed to investigate the fundamental acoustics properties of the Lattice-Boltzmann method. The propagation of planar acoustic waves is studied to determine the resolution dependence of numerical dissipation and dispersion. The two setups considered correspond to the temporal decay of a standing plane wave in a periodic domain, and the spatial decay of a propagating planar acoustic pulse of Gaussian shape. Theoretical dispersion relations are obtained from the corresponding temporal and spatial analyses of the linearized Navier-Stokes equations. Comparison of theoretical and numerical predictions show good agreement and demonstrate the low dispersive and dissipative capabilities the Lattice-Boltzmann method. The analysis is performed with and without turbulence modeling, and the changes in dissipation and dispersion are discussed. Overall, the results show that the Lattice-Boltzmann method can accurately reproduce time-explicit acoustic phenomena.

Hypothesizing that agraphia in Alzheimer's disease (AD) reflects disturbances in multiple cognitive domains, we evaluated writing samples from 33 patients meeting strict criteria for probable AD. We found agraphia to be common on a standard narrative writing task. When compared with 41 education- and age-matched normal control subjects, AD patients had significantly lower writing scores, wrote significantly fewer words, mentioned significantly fewer categories of information, and were significantly more likely to make writing errors. On stepwise regression procedures, neuropsychological measures of visuoperceptual impairment and disease severity were the strongest predictors of agraphia, but other analyses indicated that measures of language, praxis, and attention could also contribute significantly to agraphia. On two writing tasks, we failed to confirm the previous contention that agraphia is a marker for familial AD. However, there was a highly significant interaction between family history, oral naming, and writing: patients with nonfamilial AD, but not those with a family history of dementia, showed a strong correlation between naming and writing performance. We conclude that agraphia in AD can be variously determined and that agraphia is not a reliable marker for familial disease.