Persistence of preference for a flavor presented in simultaneous compound with sucrose

Rats exposed to a simultaneous compound of a flavor and sucrose subsequently exhibited a preference for the flavor over water. This preference persisted across repeated testing even though the flavor was presented in the absence of sucrose. The preference did, however, extinguish if the rats were hungry when trained or tested, or if they had been reexposed to sucrose between training and test. Though failing to extinguish the preference, presentation of the flavor outside the compound protected it from the effects of sucrose devaluation, indicating that these presentations extinguished the within-compound association between the flavor and sucrose. The authors conclude that the hedonic reaction elicited by sucrose imbues the flavor with the same hedonic properties, and these properties maintain the preference independently of the flavor-sucrose association.     

An assessment of the extent of child maltreatment using administrative databases

This study examined the extent of violence toward children and factors associated with child maltreatment in Florida using a cohort of children (N=499,330) who were adjudged to be victims of maltreatment between July 1, 1996, and June 30, 2003. To assess the extent of maltreatment, five indicators were proposed and examined. Multivariate analyses found that prior referral, having more than one type of maltreatment during an initial incident, and caregiver absence best predicted the recurrence of maltreatment. Caregivers' alcohol and substance use were strong predictors of neglect and threatened harm but not of abuse. Finally, multilevel analyses found that older, nonminority girls with histories of prior referrals were significantly (psuedo-zs>2.00) more likely to experience high degrees of incident severity. Caregivers' substance use, excluding alcohol, also was significantly linked to incident severity. Implications of the findings are discussed.     

Virtual reality exposure therapy: 150-degree screen to desktop PC.

Virtual reality exposure therapy (VRET) developed using immersive or semi-immersive virtual environments present a usability problem for practitioners. To meet practitioner requirements for lower cost and portability VRET programs must often be ported onto desktop environments such as the personal computer (PC). However, success of VRET has been shown to be linked to presence, and the environment's ability to evoke the same reactions and emotions as a real experience. It is generally accepted that high-end virtual environments (VEs) are more immersive than desktop PCs, but level of immersion does not always predict level of presence. This paper reports on the impact on presence of porting a therapeutic VR application for schizophrenia from the initial research environment of a semi-immersive curved screen to PC. Presence in these two environments is measured both introspectively and across a number of causal factors thought to underlie the experience of presence. Results show that the VR exposure program successfully made users feel they were "present" in both platforms. While the desktop PC achieved higher scores on presence across causal factors participants reported they felt more present in the curved screen environment. While comparison of the two groups was statistically significant for the PQ but not for the IPQ, subjective reports of experiences in the environments should be considered in future research as the success of VRET relies heavily on the emotional response of patients to the therapeutic program.     

Ernst Mach and the episode of the monocular depth sensations

Although Ernst Mach is widely recognized in psychology for his discovery of the effects of lateral inhibition in the retina ("Mach Bands"), his contributions to the theory of depth perception are not as well known. Mach proposed that steady luminance gradients triggered sensations of depth. He also expanded on Ewald Hering's hypothesis of "monocular depth sensations," arguing that they were subject to the same principle of lateral inhibition as light sensations were. Even after Hermann von Helmholtz's attack on Hering in 1866, Mach continued to develop theories involving the monocular depth sensations, proposing an explanation of perspective drawings in which the mutually inhibiting depth sensations scaled to a mean depth. Mach also contemplated a theory of stereopsis in which monocular depth perception played the primary role.     

Phonological priming reflects lexical competition

A phonological relationship between a prime and a target produces facilitation when one or two initial phonemes are shared (low-similarity facilitation) but produces interference when more phonemes are shared (high-similarity interference; Slowiaczek & Hamburger, 1992). Although low-similarity facilitation appears to be a strategic effect (Goldinger, Luce, Pisoni, & Marcario, 1992), this result cannot generalize to high-similarity interference because the two effects are dissociated (Slowiaczek & Hamburger, 1992). In the present study, strategic processing in high-similarity interference was investigated. The phonological relatedness proportion (PRP) and the prime-target interstimulus interval (ISI) were varied in a shadowing experiment. Low-similarity facilitation was found only with a high PRP and long ISI, but high-similarity interference was found regardless of PRP and ISI. These results suggest that strategies influence low-similarity facilitation, but high-similarity interference reflects automatic processing.     

An analysis of binocular slant contrast

When a small frontoparallel surface (a test strip) is surrounded by a larger slanted surface (an inducer), the test strip is perceived as slanted in the direction opposite to the inducer. This has been called the depth-contrast effect, but we call it the slant-contrast effect. In nearly all demonstrations of this effect, the inducer's slant is specified by stereoscopic signals; and other signals, such as the texture gradient, specify that it is frontoparallel. We present a theory of slant estimation that determines surface slant via linear combination of various slant estimators; the weight of each estimator is proportional to its reliability. The theory explains slant contrast because the absolute slant of the inducer and the relative slant between test strip and inducer are both estimated with greater reliability than the absolute slant of the test strip. The theory predicts that slant contrast will be eliminated if the signals specifying the inducer's slant are consistent with one another. It also predicts reversed slant contrast if the inducer's slant is specified by nonstereoscopic signals rather than by stereo signals. These predictions were tested and confirmed in three experiments. The first showed that slant contrast is greatly reduced when the stereo-specified and nonstereo-specified slants of the inducer are made consistent with one another. The second showed that slant contrast is eliminated altogether when the stimulus consists of real planes rather than images on a display screen. The third showed that slant contrast is reversed when the nonstereo-specified slant of the inducer varies and the stereo-specified slant is zero. We conclude that slant contrast is a byproduct of the visual system's reconciliation of conflicting information while it attempts to determine surface slant.     

Initial hospitalization and community tenure outcomes of intensive case management for children and youth with serious emotional disturbance

Since 1988 New York State's Children and Youth Intensive Camse Management (CYICM) program has enrolled more than 1,700 children. The program goal is to maintain children in the least restrictive environment approriate to their needs. This linkagke and advocacy focussed program uses a small caseload and flexible service money to meet its goal. We review the program model, describe the enrolled children, highlight some of the problems associated with determining program outcomes, and present the outcomes related to hospitalization and community tenure. Using two analytic techniques, CYICM was shown to be associated with fewer hospital admissions and fewer days in the hospital over a two-year period following the intervention of CYICM than prior to enrollment.     

The asymmetry of lateral interference in visual letter identification

Asymmetry of masking refers to the fact that a masking letter placed on the peripheral side of a target in the visual field will interfere more with recognition of the target than will a masking letter placed on the central side of the target. The experiments in this paper show that lateral masking for a pair consisting of a single target and a single mask cannot be entirely explained by processing interference caused by the mask but that masking ]has a component of purely sensory interference. Furthermore, the asymmetry of masking at the sensory level, when all sources of processing interference are eliminated, can be explained in terms of the falloff in acuity from the center to the periphery of the retina. The sensory component of masking is asymmetrical because, with the target at a constant retinal location, the target-plus-mask configuration is, as a whole, more peripherally located with a peripheral mask than a central one, and it is the location of the target-plus-mask configuration that determines performance.     

Discontinuity of seen motion reduces the visual motion aftereffect

Would a motion-picture film of a rotating spiral induce a spiral aftereffect? This question was studied in two experiments in which Ss viewed an animated film of circles collapsing to a point. The rate of apparent motion of the collapsing circles and the discontinuity of motion—the length of jump between successively projected circles—were varied independently. A visual aftereffect like the spiral aftereffect was created. The aftereffect increased in strength and duration with the rate of motion, but at all rates of motion it declined as discontinuity of motion increased. The results are taken as evidence that motion aftereffects are caused by selective fatigue of small, directionally sensitive motion-receptive fields.