Design considerations for an on-line computer system for automated psychiatric assessment

The computer-assisted multidisciplinary Psychiatric Assessment Unit at the Salt Lake City VA Hospital required a unique computer system. Design considerations and procedures for development of a Psychiatric Real-Time Information System for Management (PRISM) are outlined. This design is presented as an example for others considering implementing on-line systems. Advantages of the approach are discussed.     

Piagetian measures of cognitive development for children up to age two

This paper proposes a measure of cognitive development which is based primarily on Piaget's concepts. The choice of the particular items was determined by their assumed relation to general representational ability, including linguistic and nonverbal communication abilities. The present approach is distinguished from those of some linguists who suggest that a child's early linguistic development is not compatible with his cognitive skills and, thus, that a child's grammatical competence implies the existence of some innate set of principles for the generation of language. In contrast, the present approach hypothesizes that a child's cognitive skills during the first 2 years, particularly nonverbal representational abilities, not only precede but enhance his subsequent acquisition of language. The assumption that the items of the proposed scale together test a common ability was supported by a multidimensional homogeneity analysis of the scale, which indicated that it defines an essentially unitary ability dimension and also has strong ordinal characteristics.This study was supported by U.S. Public Health Service Grant MH 13509. This is an updated version of a paper that was presented at the International Days of Sociolinguistics, 1969, Rome, Italy.     

On the form of stimulus generalization curves for visual intensity

Twelve pigeons were given successive discrimination training involving variable-interval reinforcement for key pecking in the presence of one intensity of monochromatic light randomly alternated with extinction for pecking during another intensity. All of the pigeons were then tested in extinction for generalization along the intensity dimension, and all showed a displacement of maximal responding from the positive stimulus in the direction opposite the negative stimulus. For six of the pigeons, for which the test included only three values beyond the positive stimulus, four showed peaked gradients but two did not, showing monotonic gradients with maximal responding to the most extreme test value. For another six pigeons tested over a wider range, all showed peaked gradients. Thus, when a sufficiently wide range of test values is employed, generalization gradients for visual intensity have the same peaked form as do gradients for qualitative visual dimensions such as wavelength or line angle.     

Age differences in peripheral perceptual processing: a monoptic backward masking investigation

Peripheral processes in vision were investigated in two experiments involving monoptic backward masking with random noise. For young and old subjects, peripheral processing time (represented by stimulus onset asynchrony of target and mask) was characterized as a power function of target energy. Although processing time for both age groups showed a similar rate of decline with increasing target energy, old subjects processed targets more slowly at all energy levels. Results were independent of education, sex, and criterion differences between young and old. Target duration was related to critical interstimulus interval, such that stimulus onset asynchrony between target and mask was approximately constant for a given target energy within each age group. Evidence suggests that peripheral processing begins with target onset and that processing time is best characterized by a power function relating stimulus onset asynchrony of target and mask to target energy.     

Organizational preparedness for change: Staff acceptance of an on-line computer-assisted assessment system

An on-line assessment system is briefly described. Previous positive evaluation studies are summarized. Results of studies of staff acceptance and staff preparedness for change are reported. Findings are interpreted in terms of the need for planning for change. Implications related to the acceptance of other on-line computer systems in psychology are discussed.     

Eye height scaling of absolute size in immersive and nonimmersive displays

Eye-height (EH) scaling of absolute height was investigated in three experiments. In Experiment 1, standing observers viewed cubes in an immersive virtual environment. Observers' center of projection was placed at actual EH and at 0.7 times actual EH. Observers' size judgments revealed that the EH manipulation was 76.8% effective. In Experiment 2, seated observers viewed the same cubes on an interactive desktop display; however, no effect of EH was found in response to the simulated EH manipulation. Experiment 3 tested standing observers in the immersive environment with the field of view reduced to match that of the desktop. Comparable to Experiment 1, the effect of EH was 77%. These results suggest that EH scaling is not generally used when people view an interactive desktop display because the altitude of the center of projection is indeterminate. EH scaling is spontaneously evoked, however, in immersive environments.     

Mood, personality disorder symptoms and disability in obsessive compulsive hoarders: a comparison with clinical and nonclinical controls

Hoarding is a symptom of obsessive compulsive disorder (OCD), as well as a diagnostic criterion for obsessive compulsive personality disorder (OCPD). One recent study suggests that people who suffer from compulsive hoarding report more general psychopathology than people who do not [Frost, R.O., Krause, M.S., & Steketee, G. (1996). Hoarding and obsessive compulsive symptoms. Behavior Modification, 20, 116-132]. The present study addressed whether persons with OCD hoarding exhibit more depression, anxiety, OCD and personality disorders symptoms than community controls, OCD nonhoarders, or other anxiety disorder patients. Disability was also examined. Hoarding subjects were older than the other three groups, but age did not account for any of the differences observed among the groups. Compared to controls, OCD hoarding, nonhoarding OCD and anxiety disorder patients showed elevated YBOCS scores, as well as higher scores on depression, anxiety, family and social disability. Compared to nonhoarding OCD and anxiety disorder patients, OCD hoarding patients scored higher on anxiety, depression, family and social disability. Hoarding subjects had greater personality disorder symptoms than controls. However, OCD hoarding subjects differed from OCD nonhoarding and anxiety disorder subjects only on dependent and schizotypal personality disorder symptoms. The findings suggest that hoarding is associated with significant comorbidity and impairment compared to nonhoarding OCD and other anxiety disorders.     

Intrinsic feedback, interpolation, and the closed-loop theory

The amount of experience of a target location, or its surrounding locations, was manipulated to test Adams' (1971) prediction that the perceptual trace (stored perception of the correct response) is based on repeated sensations of the correct response. Sixteen learning trials, each followed by knowledge of results, on a linear-positioning task were permitted for all subjects. Each learning trial required movement to an adjustable physical stop. In learning condition without target experience, movements never terminated in a zone within which the target was interpolated. Other groups experienced movements terminating at the target point. The strength of the perceptual trace was inferred from the ability to move to the target during 20 test trials with the stop removed and without knowledge of the results. Slow movements could be made to a novel location equally as well as to a repeatedly practiced location.