Reduction of left visual field lexical decision accuracy as a result of concurrent nonverbal auditory stimulation

To investigate whether concurrent nonverbal sound sequences would affect visual-hemifield lexical processing, lexical-decision performance of 24 strongly right-handed students (12 men, 12 women) was measured in three conditions: baseline, concurrent neutral sound sequence, and concurrent emotional sound sequence. With the neutral sequence, Naveteru, Roy, Ovelac, and Steinling (1992) had observed a right greater than left cerebral blood flow, and an opposite pattern with the emotional sequence. In the present study, the neutral sound sequence induced a significant accuracy reduction for lexical decisions to stimuli presented in the left visual field. It is hypothesized that RH activation in response to neutral sounds interferes with the limited lexical processing resources of that hemisphere.     

Perception of biological motion: A stimulus set of human point-light actions

We present a set of stimuli representing human actions under point-light conditions, as seen from different viewpoints. The set contains 22 fairly short, well-delineated, and visually “loopable” actions. For each action, we provide movie files from five different viewpoints as well as a text file with the three spatial coordinates of the point lights, allowing researchers to construct customized versions. The full set of stimuli may be downloaded fromwww.psychonomic.org/archive/.     

Parallel allocation of attention prior to the execution of saccade sequences

In a series of 5 experiments, the allocation of attention prior to the execution of saccade sequences was examined by using a dual-task paradigm. In the primary task, participants were required to execute a sequence of 2 endogenous saccades. The secondary task was a forced-choice letter identification task. During the programming of the saccade sequences, letters were briefly presented at the saccade goals and at no-saccade locations. The results showed that performance was better for letters presented at any of the saccade goals than for letters presented at any of the no-saccade locations. The results support a spatial model that assumes that prior to the execution of a saccade sequence, attention is allocated in parallel to all saccade goals. ((c) 2003 APA, all rights reserved)     

Perception of surface reflectance of 3-D geometrical shapes: influence of the lighting mode

We examined in three experiments whether the perception of surface reflectance in 3-D geometrical shapes is influenced by the mode of lighting, the level of surface reflectance, the number of polyhedral faces, and the regularity of polyhedral shape. As stimuli, we used simulations of regular polyhedra in a 2AFC constant-stimuli procedure to measure how large variations in the reflectance needed to be for observers to be able to tell whether the whole surfaces were uniform or non-uniform. In almost all the cases observers were more successful in discriminating non-uniform polyhedra in the hemispherical diffuse lighting conditions than in the collimated lighting conditions. The different levels of reflectance had no effect on the discrimination of non-uniformity. Second, as the number of faces of the shape increased, discrimination thresholds became lower, indicating that the interpretation of reflectance variations was better when a shape had many faces. Finally, the regularity of the shape, such as the central symmetry, was not an important factor. These results suggest that the interpretation of surface reflectance is more precise when surfaces have less variance in relative strengths between the face luminance values; these surfaces were the ones obtained under hemispherical diffuse lighting.     

MMPI-2 and MCMI-III scores among dutch inpatient substance abusers: Assessing correspondence and cross-cultural equivalence

The Millon Clinical Multiaxial Inventory (MCMI-II and MCMI-III) and the Minnesota Multiphasic Personality Inventory (MMPI-2) were applied to 263 Dutch inpatient substance abusers with multiple psychiatric diagnoses, and the results compared with those of 306 North-American substance abusers studied by Ward (1995). We looked for structural similarity both across groups (per instrument) and across the two instruments (per sample), using principal components analysis and congruence analysis. The component structure found by Ward was partly replicated in the Dutch group, thus cross-validating the use of the two instruments with these patients. Moreover, as found by Ward, the MMPI-2 content and supplementary scales of the Dutch sample proved to be important determinants of the first three MMPI-2 components, adding to convergent validity. Questions remained about the influence of the (dis)continuity of MCMI-II and MCMI-III on the replicability of the MCMI components.     

State-dependent and odor-mediated anemotactic responses of a micro-arthropod on a novel type of locomotion compensator

A novel type of locomotion compensator was designed and tested for its use in orientation behavior experiments with a predatory mite. In this apparatus, displacements of the test animal in the two-dimensional plane are recorded using video equipment and a servosphere that keeps the animal in focus. Thex andy displacements are registeredusing two rotation encoders and are compensated using a pair of servo-motors, in such a way that the animal is always positioned on top of the sphere, yet moves freely. Well-fed and starved predators were tested for their responses to (1) still air, (2) a stimulus-free air flow, (3) an air flow with odors from uninfested Lima bean leaves, and (4) an air flow with odors from Lima bean leaves infested by plant-feeding mites, the prey of the predatory mites. Anemotactic responses of adultPhytoseivlus persimilis females were feeding state dependent. Well-fed predators moved downwind under Treatments 1–3 but moved neither up-nor downwind in the presence of odors from infested plants (Treatment 4). Starved predators moved upwind under all treatments. These results are in agreement with those of earlier studies in a wind tunnel, and therefore, the new type of locomotion compensator (LC-100) offers an excellent method for studying the orientation behavior of micro-arthropods.     

Utility of Behavior Ratings by Examiners During Assessments of Preschool Children With Attention-Deficit/Hyperactivity Disorder

This study examines the clinical utility of behavior ratings made by nonclinician examiners during assessments of preschool children with Attention-Deficit/Hyperactivity Disorder (AD/HD). Matched samples of children with (n = 127) and without (n = 125) AD/HD were utilized to test the internal, convergent, concurrent, and incremental validity of ratings completed by examiners on the Hillside Behavior Rating Scale (HBRS). Results indicated that HBRS ratings were internally consistent, possessed sufficient interrater reliability, and were significantly associated with parent and teacher reports of AD/HD when controlling for age, gender, intelligence, and symptoms of other psychopathology. HBRS ratings also were significantly associated with other measures of functioning, and provided a significant increment in the prediction of impairment over parent and teacher report alone. These findings suggest that behavioral ratings during testing provide a unique source of clinical information that may be useful as a supplement to parent and teacher reports.     

The Development of Person–Vocation Fit: A Longitudinal Study Among Young Employees

This two-phase panel study examines the development of the congruence between vocational interests and perceived skill requirements. Participants were 492 Dutch men and women between 18 and 26 years old, with a paid job in both phases. Three hypotheses inspired by the theory of work adjustment (Dawis and Lofquist 1984) and congruence theory (Holland 1992) were tested, using a composite index of fit proposed by Cronbach and Gleser (1953). The first hypothesis proposing that participants experiencing incongruence between their vocational interests and their perceived skill requirements are dissatisfied with their job was supported. The hypothesis that incongruence has a positive relationship with job change and a negative relationship with tenure was not confirmed. The expectation that the congruence between vocational interests and perceived skill requirements increases over time was confirmed. Furthermore, exploring determinants of change in vocational interests and perceived skill requirements, it was found that change in these domains was predicted by different variables, educational level being the only common factor. It is concluded that this study supports the longitudinal propositions of prevailing work-related person-environment fit theories.     

The Burden of Dementia: A Medical and Research Perspective

Alzheimer's disease remains the most common form of dementia. Dementia symptoms vary depending on individual personality, life experience, and social and cultural influences. As dementia progresses, involvement of multi-disciplinary health care professionals is needed to manage the disease. Alzheimer research is progressing rapidly. While 5% of all Alzheimer's disease may be genetically determined, the majority is not. Susceptibility genes can reveal the risk of contracting Alzheimer's disease. Early life risk factors such as education, nutrition, and vascular disease may increase the likelihood of dementia in later life. In the United States, two acetylcholinesterase inhibitors have been approved as cognitive enhancers. Possible prevention and symptomatic treatment interventions have focused on estrogen replacement therapy, antioxidants, and anti-inflammatory medications. Research advances have improved the clinical management of dementia. Ethical implications to the patient, family, and society are multiple and remain challenging.