The Time Course and Impact of Consumers' Erroneous Beliefs about Hedonic Contrast Effects: Figure 1

2003 ◽  
Vol 29 (4) ◽  
pp. 507-516 ◽  
Author(s):  
Nathan Novemsky ◽  
Rebecca K. Ratner
Keyword(s):  
Time Course ◽  
Contrast Effects ◽  
Erroneous Beliefs ◽  
Hedonic Contrast

Hedonic contrast effects in multi-product food evaluations differing in complexity

2018 ◽  
Vol 63 ◽  
pp. 159-167 ◽  
Author(s):  
Jagoda Mazur ◽  
Rafal Drabek ◽  
Anne Goldman
Keyword(s):  
Contrast Effects ◽  
Hedonic Contrast

scholarly journals The time course of chromatic adaptation under immersive illumination

2020 ◽  
Author(s):  
Gaurav Gupta ◽  
Naomi Gross ◽  
Ruben Pastilha ◽  
Anya Hurlbert
Keyword(s):  
Time Course ◽  
Growth Function ◽  
Chromatic Adaptation ◽  
Test Surface ◽  
Local Contrast ◽  
Contrast Effects ◽  
Colour Constancy ◽  
Relative Closeness ◽  
Wide Range ◽  
Proportional Rate

AbstractChromatic adaptation is a major contributory mechanism to constancy, yet its extent depends on many factors - spectral, spatial and temporal - which vary between studies and hence may contribute to differences in reported constancy indices. Here, we use the achromatic adjustment method to characterise the temporal progression of chromatic adaptation under a wide range of illuminations in an immersive environment. We control both the spectral properties of the illumination at the eye and the spatial context of the adjusted surface, to disentangle global adaptation from local contrast effects. We measure the timecourse of chromatic adaptation by assessing achromatic adjustments in 6 discrete time slots over 340 seconds. We find that the change over time of the adaptation state, proximally indicated by colour constancy indices (quantified by the relative closeness of the perceptual whitepoint to the test illumination chromaticity), (a) can be modelled by a proportional rate growth function, typically requiring more than 5 minutes to stabilise; (b) depends on the contrast between the test surface and its background, specifically increasing with decreasing test-background contrast; and (c) is generally similar in both extent and rate for different test illumination chromaticities. Adaptation progression does not differ significantly between illuminations on or off the daylight locus. Our results highlight the importance of considering exposure duration and stimulus configuration, as well as the distance between the pre-adaptation (reference) and test illumination chromaticities, when using achromatic adjustment as a measure of colour constancy.

Asymmetric Hedonic Contrast: Pain Is More Contrast Dependent Than Pleasure

2021 ◽  
pp. 095679762199114
Author(s):  
Guy Voichek ◽  
Nathan Novemsky
Keyword(s):  
Contrast Effect ◽  
Reference Points ◽  
Positive Outcomes ◽  
Negative Outcomes ◽  
Contrast Effects ◽  
Important Phenomenon ◽  
Hedonic Contrast ◽  
Gains And Losses

Research has shown that hedonic-contrast effects are a ubiquitous and important phenomenon. In eight studies ( N = 4,999) and four supplemental studies ( N = 1,809), we found that hedonic-contrast effects were stronger for negative outcomes than for positive outcomes. This asymmetric-contrast effect held for both anticipated and experienced affect. The effect makes risks that include gains and losses more attractive in the presence of high reference points because contrast diminishes the hedonic impact of losses more than gains. We demonstrated that the effect occurs because people are generally more attentive to reference points when evaluating negative outcomes, so drawing attention to reference points eliminates the asymmetric-contrast effect.

Hedonic Contrast Effects Are Larger When Comparisons Are Social

2018 ◽  
Vol 46 (2) ◽  
pp. 286-306 ◽  
Author(s):  
Carey K Morewedge ◽  
Meng Zhu ◽  
Eva C Buechel
Keyword(s):  
Social Comparison ◽  
Contrast Effect ◽  
Time Pressure ◽  
Social Comparisons ◽  
Social Attention ◽  
Contrast Effects ◽  
Attentional Resources ◽  
Comparison Standards ◽  
Hedonic Contrast ◽  
The Impact

Abstract A hedonic contrast effect occurs when comparing a stimulus to its alternatives makes it better or worse. We find that counterfactual comparisons induce larger hedonic contrast effects when they are also social comparisons. Hedonic contrast effects influence happiness with a food or wage more when another person receives its counterfactual alternative than when no person receives its counterfactual alternative. Social attention, the propensity to attend to the experiences of other people, underlies the larger hedonic contrast effects induced by social comparisons. People pay more attention to counterfactual alternatives when they are also social comparison standards, and this difference in the allocation of attention mediates the larger hedonic contrast effects that social counterfactual comparisons induce. Reducing attentional resources with cognitive load or time pressure reduces the impact of social counterfactual comparisons, and drawing attention to nonsocial counterfactual comparisons increases their impact. Social attention makes comparisons stronger when they are social.

Observation of biological macromolecules using various electron microscopic methods

1978 ◽  
Vol 36 (2) ◽  
pp. 170-171
Author(s):  
Mitsuo Ohtsuki ◽  
Michael Sogard
Keyword(s):  
Electron Microscope ◽  
Phase Contrast ◽  
Image Interpretation ◽  
Density Lipoprotein ◽  
Biological Macromolecules ◽  
Contrast Effects ◽  
Biological Structure ◽  
Electron Microscopic ◽  
Structural Investigations ◽  
Staining Techniques

Structural investigations of biological macromolecules commonly employ CTEM with negative staining techniques. Difficulties in valid image interpretation arise, however, due to problems such as variability in thickness and degree of penetration of the staining agent, noise from the supporting film, and artifacts from defocus phase contrast effects. In order to determine the effects of these variables on biological structure, as seen by the electron microscope, negative stained macromolecules of high density lipoprotein-3 (HDL3) from human serum were analyzed with both CTEM and STEM, and results were then compared with CTEM micrographs of freeze-etched HDL3. In addition, we altered the structure of this molecule by digesting away its phospholipid component with phospholipase A2 and look for consistent changes in structure.

Analysis of STEM micrographs of thick objects

1978 ◽  
Vol 36 (2) ◽  
pp. 106-107
Author(s):  
S. Golladay
Keyword(s):  
Inelastic Scattering ◽  
Multiple Scattering ◽  
Mass Distribution ◽  
Cross Sections ◽  
Phase Contrast ◽  
Image Point ◽  
Contrast Effects ◽  
Total Cross Sections ◽  
Elastic And Inelastic Scattering

The theory of multiple scattering has been worked out by Groves and comparisons have been made between predicted and observed signals for thick specimens observed in a STEM under conditions where phase contrast effects are unimportant. Independent measurements of the collection efficiencies of the two STEM detectors, calculations of the ratio σe/σi = R, where σe, σi are the total cross sections for elastic and inelastic scattering respectively, and a model of the unknown mass distribution are needed for these comparisons. In this paper an extension of this work will be described which allows the determination of the required efficiencies, R, and the unknown mass distribution from the data without additional measurements or models. Essential to the analysis is the fact that in a STEM two or more signal measurements can be made simultaneously at each image point.

Ultrastructural Changes of the Symbiotic Chlorella-Like Alga Isolated from Hydra Viridis

1982 ◽  
Vol 40 ◽  
pp. 320-321
Author(s):  
K.W. Lee ◽  
R.H. Meints ◽  
D. Kuczmarski ◽  
J.L. Van Etten
Keyword(s):  
Time Course ◽  
Reciprocal Cross ◽  
Ultrastructural Level ◽  
Ultrastructural Changes ◽  
Symbiotic Relationship ◽  
Cell Recognition ◽  
Green Hydra ◽  
Different Strains ◽  
Hydra Viridis

The physiological, biochemical, and ultrastructural aspects of the symbiotic relationship between the Chlorella-like algae and the hydra have been intensively investigated. Reciprocal cross-transfer of the Chlorellalike algae between different strains of green hydra provide a system for the study of cell recognition. However, our attempts to culture the algae free of the host hydra of the Florida strain, Hydra viridis, have been consistently unsuccessful. We were, therefore, prompted to examine the isolated algae at the ultrastructural level on a time course.

Destruction of Actin Filaments by Osmium Tetroxide

1977 ◽  
Vol 35 ◽  
pp. 466-467
Author(s):  
P. Maupin-Szamier ◽  
T. D. Pollard
Keyword(s):  
Actin Filaments ◽  
Time Course ◽  
Osmium Tetroxide ◽  
Rabbit Muscle ◽  
Muscle Actin ◽  
Sodium Phosphate Buffer ◽  
Transmission Electron ◽  
The Difference ◽  
Rates Of Decay ◽  
Short Time

We have studied the destruction of rabbit muscle actin filaments by osmium tetroxide (OSO4) to develop methods which will preserve the structure of actin filaments during preparation for transmission electron microscopy.Negatively stained F-actin, which appears as smooth, gently curved filaments in control samples (Fig. 1a), acquire an angular, distorted profile and break into progressively shorter pieces after exposure to OSO4 (Fig. 1b,c). We followed the time course of the reaction with viscometry since it is a simple, quantitative method to assess filament integrity. The difference in rates of decay in viscosity of polymerized actin solutions after the addition of four concentrations of OSO4 is illustrated in Fig. 2. Viscometry indicated that the rate of actin filament destruction is also dependent upon temperature, buffer type, buffer concentration, and pH, and requires the continued presence of OSO4. The conditions most favorable to filament preservation are fixation in a low concentration of OSO4 for a short time at 0°C in 100mM sodium phosphate buffer, pH 6.0.

High-Voltage Scanning Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 6-7
Author(s):  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Wave Optics ◽  
Contrast Effects ◽  
Transmission Electron ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Types Of Information ◽  
Voltage Scanning

The comparison of scanning transmission electron microscopy (STEM) with conventional transmission electron microscopy (CTEM) can best be made by means of the Reciprocity Theorem of wave optics. In Fig. 1 the intensity measured at a point A’ in the CTEM image due to emission from a point B’ in the electron source is equated to the intensity at a point of the detector, B, due to emission from a point A In the source In the STEM. On this basis it can be demonstrated that contrast effects In the two types of instrument will be similar. The reciprocity relationship can be carried further to include the Instrument design and experimental procedures required to obtain particular types of information. For any. mode of operation providing particular information with one type of microscope, the analagous type of operation giving the same information can be postulated for the other type of microscope. Then the choice between the two types of instrument depends on the practical convenience for obtaining the required Information.

Characteristic Geometry and Diffraction Contrast of Dispersed ThO2 Crystals

1969 ◽  
Vol 27 ◽  
pp. 168-169
Author(s):  
R. J. Horylev ◽  
L. E. Murr
Keyword(s):  
Dark Field ◽  
Particle Orientation ◽  
Contrast Effects ◽  
Strain Fields ◽  
Diffraction Contrast ◽  
Dispersed Particles ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Particle Images ◽  
Diffraction Effects

Smith has shown by dark-field electron microscopy of extracted ThO2 particles from TD-nickel (2% ThO2) that they possess single crystal characteristics. It is generally assumed that these particle dispersions are incoherent. However, some diffraction effects associated with the particle images appeared to be similar to coherency strain fields. The present work will demonstrate conclusively that ThO2 dispersed particles in TD-nickel (2% ThO2) and TD-NiCr (2% ThO2, 20% Cr, Ni) are single crystals. Moreover, the diffraction contrast effects are extinction fringes. That is, these effects arise because of the particle orientation with respect to the electron beam and the extinction conditions for various operating reflections The particles are in fact incoherent.

Sign in / Sign up

Export Citation Format

Share Document