Normative data for a brief neuropsychological screening battery. Multicenter AIDS Cohort Study.

This study reports normative data for a group of 733 homosexual/bisexual men stratified by age (range 25 to 54 years) and by education on the following six neuropsychological tests: (1) Digit Span (WAIS-R), (2) Rey Auditory Verbal Learning Test, (3) Symbol Digit Modalities Test, (4) Controlled Oral Word Association Test, (5) Grooved Pegboard, and (6) The Trail Making Test. Analysis demonstrates that both age and education are important determinants of performance for several of these measures.     

The compensation for movement-produced changes of object orientation

When one moves forward, one views objects to the side of one’s path successively from different directions. In the mover’s visual field, such objects change their orientation; relative to him they undergo a partial rotation. Although this rotation is given in several ways, it is hardly ever perceived. This is due to a compensating process that takes O’s change in position relative to the object into account. We demonstrated the existence of this compensating process and measured the accuracy with which it operates by means of a device that made an object turn in response to O’s position change so that the normal rotation of a stationary object relative to the moving O could be augmented or diminished to various degrees.     

Semantic context and word frequency effects in visual word recognition

Semantic context and word frequency factors exert a strong influence on the time that it takes subjects to recognize words. Some of the explanations that have been offered for the effects of the two factors suggest that context and frequency should interact, and other explanations imply additivity. In a recent study, Schuberth and Eimas reported that context and frequency effects added to determine their subjects' reaction times in a lexical decision (word vs. nonword) task. The present experiment reexamines this question with improved procedures. The data show that context and frequency do interact, with a semantic context facilitating the processing of low-frequency words more than high-frequency words.     

Investigating the relationship between product involvement and consumer decision‐making styles

• Recently, a number of studies have investigated consumer decision‐making styles (CDMS) and their importance to consumer behaviour research. However, research designs suggested to date are mainly replications of a study by Sproles and Kendall ( 1986 ) proposing eight mental characteristics, the so‐called Consumer Styles Inventory (CSI). The CSI has been applied across cultures, but without critically examining its validity and reliability. A major concern is the postulated product independence of CSI. The aim of this study is to further develop this approach, to apply it to different product categories and to investigate the relationship between product involvement and CDMS. In doing so, we conducted a survey in Great Britain and Germany, and analysed the data using exploratory and confirmatory factor analysis. Not only did we demonstrate that there is a relationship between products and CDMS, but also that CDMS are governed by consumers' perceived product involvement. Important implications for marketing practice can be derived.

Copyright © 2006 John Wiley & Sons, Ltd.     

Brain dopamine and kinematics of graphomotor functions

Three experiments were performed in an attempt to achieve a better understanding of the effect of dopamine on handwriting. In the first experiment, kinematic aspects of handwriting movements were compared between healthy participants and patients with Parkinson's disease (PD) on their usual dopaminergic treatment and following withdrawal of dopaminergic medication. In the second experiment, the writing performance of healthy participants with a hyperechogenicity of the substantia nigra as detected by transcranial sonography (TCS) was compared with the performance of healthy participants with low echogenicity of the substantia nigra. The third experiment examined the effect of central dopamine reduction on kinematic aspects of handwriting movements in healthy adults using acute phenylalanine and tyrosine depletion (APTD). A digitising tablet was used for the assessment of handwriting movements. Participants were asked to perform a simple writing task. Movement time, distance, velocity, acceleration and measures of fluency of handwriting movements were measured. The kinematic analysis of handwriting movements revealed that alterations of central dopaminergic neurotransmission adversely affect movement execution during handwriting. In comparison to the automatic processing of handwriting movements displayed by control participants, participants with an altered dopaminergic neurotransmission shifted from an automatic to a controlled processing of movement execution. Central dopamine appears to be of particular importance with regard to the automatic execution of well-learned movements.