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At least 1,261 records · Page 70Linked to original sources
PubMed2004

Believing is seeing? Investigating the perceived accuracy of criminal psychological profiles.

This study investigated whether perceptions of criminal psychological profiles are influenced by the identity of the profile's author. Police officers were given a profile they were told was written by either a professional profiler or by an unspecified author. When judged in relation to the actual perpetrator of the crime, police officers tended to perceive greater accuracy in a profile when it was labeled as authored by a professional profiler independent of the actual content of the profile. But officers' judgments of the usefulness of the profile were not affected by knowledge of who wrote the profile. Explanations for this result focus on the ambiguous nature of criminal profiles and how this ambiguity enhances the likelihood that beliefs about the validity of profiling can color perceptions of the content of the profile.

Adult↗
PubMed2000

Perceptual differences between stroke patients with cerebral infarction and intracerebral hemorrhage.

OBJECTIVE: To assess perceptual performances of patients with intracerebral hemorrhage (ICH) compared with those of ischemic patients early after stroke and to analyze the psychometric properties of three perceptual tests used in the study. DESIGN: Cross-sectional study. SETTING: A rehabilitation unit at a teaching hospital. PATIENTS: Twenty-two stroke patients with ICH and 22 demographically matched stroke patients with infarction. MAIN OUTCOME MEASURES: Loewenstein Occupational Therapy Cognitive Assessment (LOTCA), Rivermead Perceptual Assessment Battery (RPAB), and Motor-Free Visual Perception Test (MVPT). RESULTS: Stroke patients with ICH had significantly more severe deficits on a task of thinking operations than did patients with infarction. A significant lateralized effect of stroke existed in the ICH group, with patients with right-hemisphere strokes scoring lower than patients with left-hemisphere strokes on the figure-ground discrimination subtest of the RPAB. A considerable overlap among the three instruments was found. Yet, the observed correlations between supposedly similar subtests from the tests proved to be moderate, indicating that to a certain extent these test measures tap different perceptual processes. Four factors were generated from a joint LOTCA-RPAB-MVPT factor analysis. They assessed different facets of perceptual functioning, including higher-level and lower-level perceptual skills, part/whole conceptual integration, and color perception. This factor pattern accounted for 75.5% of the variance. CONCLUSIONS: Higher-level perceptual functions tend to be relatively susceptible to ICH stroke pathology early in the course of the disease. This information has important clinical implications in the early treatment planning for the stroke patients with ICH, such that specific compensatory strategies for these deficiencies should be devised to facilitate a successful rehabilitation. Knowledge regarding the influences of specific deficits on the performance of daily activities may also be useful to the patients' family.

Adult↗
PubMed2004

Investigating human color preferences in the perception of complex three-dimensional structures.

This article describes preliminary results of a investigation that addresses the problem of human color perception in the visual analysis of complex three-dimensional shapes. We built 3D visualization models of synthetic neural cells, and designed two experiments to identify user preferences for color when observing and executing tasks on these 3D models. Though preliminary, the results obtained from these experiments are consistent and indicate that some trends exist that deserve further investigation.

Color Perception↗
PubMed1995

Association of acquired color vision defects in blue cone monochromatism.

The retinal functions of a 43-year-old man with diabetic retinopathy in a family affected by blue cone monochromatism were studied. While changes in visual acuity and color vision were similar to those seen in patients affected by rod monochromatism, and his spectral sensitivities on high intensity background and his threshold versus intensity curve indicated only suggestive blue cone function, mass electroretinograms (ERG) findings demonstrated well preserved blue cone function. The disparity in blue cone function between psychophysical and mass electroretinographical evaluation may be caused by the difference in how much the fovea influenced each testing. Diabetic retinopathy most likely caused significant reduction of the psychophysical blue cone function and resulted in clinical findings similar to rod monochromatism. The mass blue cone ERG was useful to differentiate blue cone monochromatism from rod monochromatism in this diabetic patient.

Adult↗
PubMed2003

Beyond visual acuity: new and complementary tests of visual function.

Visual acuity is an essential component of the routine ophthalmic examination and the most common measure of visual function. There is increasing recognition, however, of the need to evaluate visual function beyond the limited extent afforded by visual acuity. The primary objective of this article is to introduce a variety of new and lesser-used techniques for measuring visual function that complement visual acuity assessment, each of which has been shown to detect visual dysfunction in patients with normal visual acuity.

Color Perception↗
PubMed2006

Macular pigment: a review of current knowledge.

The existence of the macula lutea of the human retina has been known for more than 200 years. It is established that the xanthophylls lutein and zeaxanthin are responsible for the yellow color. The effect of macular photopigments on blue-light filtration and color perception is well established. It has been postulated that the pigment might serve to reduce chromatic aberration and to improve visual acuity. The antioxidant capabilities of these xanthophylls combined with their ability to trap short-wavelength light may serve to protect the outer retina, retinal pigment epithelium, and choriocapillaris from oxidative damage. Current ideas on the pathophysiology of age-related macular degeneration may be compatible with the proposed function of lutein and zeaxanthin. This review will summarize our knowledge about macular pigment regarding current efforts in research and the epidemiology of age-related eye disease.

Carotenoids↗
PubMed1985

Improved color test results with large-field viewing in dichromats.

Standard methods for screening color vision defects may be expected to underestimate a color defective's complete chromatic discrimination abilities because the viewing field is confined to the fovea (central 2 degrees). Large-field (8 degrees) Farnsworth-Munsell 100-hue and dichotomous (D-15) tests were constructed. The 100-hue test, along with its small-field counterpart, was administered to five deuteranopes (green defectives) and four protanopes (red defectives). The D-15 small- and large-field tests were given to these same subjects with the addition of two deuteranopes and one protanope. Both deuteranopes and protanopes showed marked improvement on the large-field D-15 and 100-hue tests. This improvement in performance for large-field over small-field viewing is consistent with color-matching data, which show large-field trichromacy in observers who have been demonstrated to be small-field red-green dichromats. These results suggest that tests confined to central fovea viewing provide an incomplete functional description of the color vision of an appreciable number of classic dichromats.

Color Perception↗
PubMed1980

Polymorphisms of red-green vision in some populations of Southern Africa.

Some 5,000 schoolboys of the Khoikhoi, Negro, "Coloured," and Malay populations were screened with the Ishihara plates, and those with defective red-green vision were diagnosed with an anomaloscope. The findings are presented in terms of the six protan and deutan mutant alleles, a few large population-samples (e.g., Nama and Zulu) being characterized by absence of the allele for protanopia. The overall frequencies of mutants range from less than 1% to over 4%. No correspondence was found between these data and linguistic affinities of eight Bantu-speaking groups, nor between the frequencies of colorblindness and previously estimated proportions of San genes in these eight populations; on the other hand, a north-south cline of increasing frequences of mutants and of dichromacies among the Bantu-speakers was noted. The overall frequency of defective red-green vision among Cape Coloureds, 3.3%, is compatible with previously estimated racial composition of this population. The Malay sample is characterized by the highest frequency of protan mutants (2%), a 1:1 protan-deutan ratio, and an overall frequency of 4% of red-green defects. The study illustrates the potential value of anomaloscopic characterization of colorblindness in attempts to evaluate human evolutionary processes.

Adolescent↗