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81.
Colored neon flanks and line gap enhancement 总被引:1,自引:0,他引:1
When a colored line connects two black (or differently colored) lines across a gap, colored neon flanks are seen on either side of it. These flanks extend over gap sizes of 50 min arc foveally and are not explained by Bezold-type assimilation. They may be elicited by black lines as short as 6 min arc adjoining the colored line at each end. To maximize these flanks, the black and colored lines must appear linearly continuous. Nonaligned junctions weaken the effect and an angular tilt of more than 40 dog destroys it. In this and other respects, (local) neon flanks are similar to van Tuijl's (global) neon color spreading (1975). Both phenomena have analogs in brightness perception. We propose that neon spreading is a lateral extension of neon flanks across the empty space between them, and discuss similarities of these effects with other brightness illusions (Schumann, Prandtl, Ehrenstein). For this group of illusions the term "line gap enhancement" is introduced to imply perceptual enhancement of changes in brightness and/or color along lines. Correspondences between the psychophysical properties and structural prerequisites for line gap enhancement on one hand and neuronal response properties of end-zone inhibited (hypercomplex) cortical cells on the other are discussed. 相似文献
82.
Gordon E. Legge 《Vision research》1984,24(4):385-394
Quadratic summation is presented as a rule that describes binocular contrast summation. The rule asserts that for left-eye and right-eye contrasts CL and CR, there is an effective binocular contrast C given by the formula:Pairs of left-eye and right-eye stimuli that produce equal values of C are equivalent. Quadratic summation is applied to the results of experiments in which stimuli presented to the two eyes differ only in contrast. It provides a good, first-order account of binocular summation in contrast detection, contrast discrimination, dichoptic masking, contrast matching and reaction time studies. A binocular energy-detector model is presented as a basis for quadratic summation. 相似文献
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Food ingestion induces homeostatic sensations (satiety, fullness) with a hedonic dimension (satisfaction, changes in mood) that characterize the postprandial experience. Both types of sensation are secondary to intraluminal stimuli produced by the food itself, as well as to the activity of the digestive tract. Postprandial sensations also depend on the nutrient composition of the meal and on colonic fermentation of non-absorbed residues. Gastrointestinal function and the sensitivity of the digestive tract, i.e., perception of gut stimuli, are determined by inherent individual factors, e.g., sex, and can be modulated by different conditioning mechanisms. This narrative review examines the factors that determine perception of digestive stimuli and the postprandial experience. 相似文献
85.
《Journal of the Academy of Nutrition and Dietetics》2022,122(8):1543-1557
BackgroundA recent Delphi study indicated that, compared with eating disorder (ED) consumers and carers, ED specialists were less likely to endorse involvement of a dietitian as a standard component of treatment. In addition, there was disagreement between these groups regarding the inclusion of a number of components of dietetic treatment.ObjectiveThis study aimed to further investigate these data to identify areas of disagreement among ED specialist dietitians, ED specialist non–dietetic clinicians, consumers, and carers with regard to outpatient dietetic treatment.Design and participants/settingThe ED specialists panel from a previous Delphi study was recoded into 2 panels: ED specialist dietitians (n = 31) and ED specialist non–dietetic clinicians (n = 48) to compare responses of these panels with responses from consumers (n = 32) and carers (n = 23).Main outcome measuresStatements in 7 categories relating to referral to dietitian, essential components of outpatient dietetic treatment regarding 4 ED patient populations, strategies to promote multidisciplinary collaboration, and skills dietitians should possess if treating patients with an ED were rated on a 5-point Likert scale.Statistical analysis performedOne-way analysis of variance was conducted with post-hoc multiple comparisons to compare mean statement ratings.ResultsThirty-seven statements (30%) showed statistically significant differences (P < .05) in responses between panels. Discrepancies were primarily observed for statements regarding how and when dietetics is included in treatment and essential components of dietetic treatment, particularly the use of behavioral tasks, such meal plans and self-monitoring. Results also highlighted deficits in participants’ understanding of core responsibilities of dietitians in ED treatment and dietitians “drifting” from delivering evidence-based components of dietetic treatment.ConclusionsResults of this study show discrepancies among ED dietitians, clinicians, consumers, and carers regarding what dietetic treatment for people with EDs should encompass. It also indicates the need for further research into optimizing dietetic treatment for EDs that is conducted in collaboration with individuals with lived experience. 相似文献
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Aurore Thibaut Vivian L. Shie Colleen M. Ryan Ross Zafonte Emily A. Ohrtman Jeffrey C. Schneider Felipe Fregni 《Burns : journal of the International Society for Burn Injuries》2021,47(3):525-537
Burn survivors experience myriad associated symptoms such as pain, pruritus, fatigue, impaired motor strength, post-traumatic stress, depression, anxiety, and sleep disturbance. Many of these symptoms are common and remain chronic, despite current standard of care. One potential novel intervention to target these post burn symptoms is transcranial direct current stimulation (tDCS). tDCS is a non-invasive brain stimulation (NIBS) technique that modulates neural excitability of a specific target or neural network. The aim of this work is to review the neural circuits of the aforementioned clinical sequelae associated with burn injuries and to provide a scientific rationale for specific NIBS targets that can potentially treat these conditions. We ran a systematic review, following the PRISMA statement, of tDCS effects on burn symptoms. Only three studies matched our criteria. One was a feasibility study assessing cortical plasticity in chronic neuropathic pain following burn injury, one looked at the effects of tDCS to reduce pain anxiety during burn wound care, and one assessed the effects of tDCS to manage pain and pruritus in burn survivors. Current literature on NIBS in burn remains limited, only a few trials have been conducted. Based on our review and results in other populations suffering from similar symptoms as patients with burn injuries, three main areas were selected: the prefrontal region, the parietal area and the motor cortex. Based on the importance of the prefrontal cortex in the emotional component of pain and its implication in various psychosocial symptoms, targeting this region may represent the most promising target. Our review of the neural circuitry involved in post burn symptoms and suggested targeted areas for stimulation provide a spring board for future study initiatives. 相似文献
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