Lightness constancy in the presence of specular highlights
Article Abstract:
Author Abstract: Visible surfaces in a natural environment often have multiple components of reflectance, including a diffuse component, by which light is scattered isotropically in all possible directions, and a specular component, by which light is reflected anisotropically within a limited range of directions. The research described in the present article was designed to investigate how these different components of reflectance influence the perception of lightness. Human observers were presented with shaded images of smoothly curved surfaces and asked to compare the relative lightness of different surface regions whose diffuse and specular components of luminance were independently manipulated. The results revealed that observers are able to discount the presence of specular highlights so that the relative lightness among different regions is determined almost entirely by the diffuse component of surface reflectance.
Publication Name: Psychological Science
Subject: Psychology and mental health
ISSN: 0956-7976
Year: 2004
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Hunger sensation in patients with compensated and uncompensated type 1 and type 2 diabetes mellitus
Article Abstract:
Type 1 and Type 2 diabetes mellitus patients experience periprandial, interprandial and nocturnal peaks in their hunger sensation. (HS). An amplification of the three peaks corresponding to meal times in compensated type 1 DM patients increases HS. In uncompensated type 1 DM patients, HS increases due to additional orectic peaks in the nocturnal and diurnal parts of the day. Interposed diurnal peaks and an increase in periprandial peaks cause elevated levels of HS in type 2 DM patients.
Publication Name: The International Journal of Eating Disorders
Subject: Psychology and mental health
ISSN: 0276-3478
Year: 1996
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