Interval length and time-use by children with AD/HD: a comparison of four models

Predictions made by 4 competing models of time use by children with AD/HD were tested using a computerized version of the Matching Familiar Figures Test in 2 studies. In Study 1 teacher-identified AD/HD children (N = 10) and non-AD/HD controls (N = 10) completed the task under 3 different trial duration conditions (5, 10, and 15 s). In Study 2 the same task was completed by a group of children with a diagnosis of Hyperkinetic Disorder (N = 12) and controls (N = 12). In both studies AD/HD children performed poorly on trials of both 5- and 15-s duration but as well as controls on the 10-s trials. This quadratic function provided support for the State Regulation Deficit model of time use in AD/HD. The value of tailoring the temporal features of learning contexts to the conceptual style of AD/HD children is discussed.     

Insights into spared memory capacity in amnestic MCI and Alzheimer's Disease via minimal interference

Impairment on standard tests of delayed recall is often already maximal in the aMCI stage of Alzheimer's Disease. Neuropathological work shows that the neural substrates of memory function continue to deteriorate throughout the progression of the disease, hinting that further changes in memory performance could be tracked by a more sensitive test of delayed recall. Recent work shows that retention in aMCI patients can be raised well above floor when the delay period is devoid of further material - 'Minimal Interference'. This memory enhancement is thought to be the result of improved memory consolidation. Here we used the minimal interference/interference paradigm (word list retention following 10 min of quiet resting vs. picture naming) in a group of 17 AD patients, 25 aMCI patients and 25 controls. We found (1) that retention can be improved significantly by minimal interference in patients with aMCI and patients with mild to moderate AD; (2) that the minimal interference paradigm is sensitive to decline in memory function with disease severity, even when performance on standard tests has reached floor; and (3) that this paradigm can differentiate well (80% sensitivity and 100% specificity) between aMCI patients who progress and do not progress to AD within 2 years. Our findings support the notion that the early memory dysfunction in AD is associated with an increased susceptibility to memory interference and are suggestive of a gradual decline in consolidation capacity with disease progression.     

Elementary school students with AD/HD: predictors of academic achievement

Academic underachievement frequently is associated with attention-deficit/hyperactivity disorder (AD/HD); however, the role of variables beyond AD/HD symptoms and cognitive mediators is unknown. Further, whether prediction models vary (a) relative to non-AD/HD students, (b) between math and reading, and (c) based on how achievement is defined has not been examined. Multiple measures (e.g., teacher ratings and behavior observations) were examined as predictors for concurrent achievement outcomes (standardized achievement test scores and report card grades) in math and reading in two samples of 1st through 4th grade children (136 with AD/HD, 53 without AD/HD). Teacher perceptions of academic skills were the strongest predictors of achievement test scores for both groups, while academic skills and enablers accounted for reading report card grades in children with AD/HD but not their normal counterparts. Implications of these findings for school-based assessment and intervention for students with AD/HD are discussed.     

Clock drawing performance and brain morphology in mild cognitive impairment and Alzheimer's disease

The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive impairment, 23 with AD and 15 healthy controls underwent high-resolution magnetic resonance imaging. Optimized voxel-based morphometry (VBM) was performed to investigate the putative association between CDT performance and gray matter (GM) density throughout the entire brain. In the first step of analysis (p<.001, uncorrected), VBM revealed a reduced GM density in numerous cortical (temporal lobe, frontal lobe, parietal lobe, cerebellum) and subcortical (thalamus, basal ganglia) brain regions to be associated with poorer CDT performance. When corrected for multiple comparisons (p<.01), the associations remained significant predominantly in the left temporal and--less pronounced--the right temporal lobe. VBM demonstrated CDT performance to depend on the integrity of widely distributed cortical and subcortical areas in both brain hemispheres with accentuation in the left-sided temporal lobe region.     

Designing Urban Experiences. The Case of Zuidas,Amsterdam

Zuidas is a new city centre, which is emerging in the outskirts of Amsterdam. The ambitious project of developing a new international city centre has been carefully planned as the Netherlands has a strong and meticulous tradition for urban planning. The planning has however not only encompassed traditional urban planning aspects such as infrastructure, environmental factors and aesthetics, but has also dealt with the design of urban experiences. Through an introduction of the framework of the structure of experiences, this article examines how urban experiences can be understood and analysed, and deals with how urban experiences can be designed through careful consideration of how experiences are constituted. Taking the psychological structure of experiences into account when designing urbanity is not only interesting, but also highly relevant as Zuidas is competing with other international venues such as La Défense, the Docklands and Potsdamer Platz.     

Printed word learning in beginning readers

Three experiments using beginning Dutch readers (7 and 8 years of age) as subjects provide evidence that visually recognizing the unique graphemic structure of words is an important component in word identification, even at rather early stages in learning to read. Only a moderate amount of practice in reading strings of letters was necessary for young children to read the regular spelling faster than an altered spelling that preserved the word sound. In normal beginners this effect appeared regardless of their ability to identify the words the first time; in learning-disabled children, matched in overall reading speed, learning about the graphemic compositions of words seems to proceed at a much slower rate. The results are discussed with regard to the importance of building accurate graphemic entries in the mental lexicon for acquiring fluency in reading.     

Effects of visual-field and matching instruction on event-related potentials and reaction time

Vertical letter pairs were presented randomly in the left and right visual hemifields in a physical identity match and name identity match condition. The reaction times showed a right visual field superiority for name matches, and a left visual field superiority for physical matches. Event-related potentials to letter pairs showed a sequence of three waves: a negative wave (N2, around 270 msec), a positive wave (P3, around 500 msec), and a broad positive slow wave (SW, around 600-700 msec), respectively. P3 and SW amplitudes were consistently larger at the left hemisphere than at the right hemisphere, regardless of the field of stimulation. At both hemispheres, N2 waves were always larger to stimuli presented in the visual field contralateral to a hemisphere than stimuli presented in the visual field ipsilateral to a hemisphere. The positive waves (P3, SW) showed the opposite pattern: smaller amplitudes to stimuli that were presented contralaterally than stimuli that were presented ipsilaterally to a given hemisphere. These results were attributed to a shift in sustained negativity on the directly stimulated hemisphere, relative to the indirectly stimulated hemisphere, reflecting either sensory at attentional processes in the posterior cerebral hemispheres.     

Matrix differential calculus with applications to simple,hadamard, and kronecker products

Several definitions are in use for the derivative of an m × p matrix function F(X) with respect to its n × q matrix argument X. We argue that only one of these definitions is a viable one, and that to study smooth maps from the space of n × q matrices to the space of m × p matrices it is often more convenient to study the map from nq-space to mp-space. Also, several procedures exist for a calculus of functions of matrices. It is argued that the procedure based on differentials is superior to other methods of differentiation, and leads inter alia to a satisfactory chain rule for matrix functions.     

Sheldon's physical-psychical typology revisited

In order to clarify some of the general findings in the literature with respect to relationships between body type and the personality dimension extraversion/introversion, typical experimental paradigms common to this field were replicated but using the first-order factors (from the R. B. Cattell, H. W. Eber, & M. M. Tatsuoka (1970, Handbook for the sixteen personality factor questionnaire, Windsor: N.F.E.R.) analysis) that load on this continuum rather than the continuum itself. Use was made of standard statistical procedures as well as discriminant analysis. The most noteworthy finding was that subjects were able to utilize the first-order factor structure for the continuum extraversion/introversion in a discriminating manner and to assign such factors in a fairly clear-cut way to three extreme body types. Personality appraisals of the mesomorphic body type and an ideal type (composed by the subjects) were shown to be virtually identical. The most positive extravert characteristics were assigned to the endomorph body build and the most positive introvert characteristics to the ectomorph. No differences in personality appraisals by male (n = 50) and female (n = 50) subjects with the exception of factor Q₂ by the ectomorphic body type were found. Both male and female subjects showed a preference for the (male) mesomorphic body type although significant differences between male and female subjects in the pattern of their distribution of preferences over the three body types were found. While the results confirm previous findings, they also extend them by the use of a first-order factor structure for the continuum extraversion/introversion and by the introduction of the explanatory concepts “extravert of affect” and “extravert of action.”