Social sharing of emotion following exposure to a negatively valenced situation

Three experimental studies are reported in which we tested the prediction that negative emotion elicits the social sharing of the emotional experience. In two experiments, participants arrived at the laboratory with a friend and then viewed one of three film excerpts (nonemotional, moderate emotion, or intense emotion) alone. Afterwards, the participants who saw the film had an opportunity to interact with the friend and their conversation was recorded. In both experiments participants who had seen the intense emotion excerpt engaged in significantly more social sharing than did participants in the other two conditions. A third experiment extended the investigation to social sharing in everyday life and replicated the previous results. Nonemotional explanations of the effects observed were also ruled out. Results are discussed in the context of the relation between emotional intensity and amount of social sharing.     

BOOK REVIEW

Chang, Leo S. and Yu Feng, The Four Political Treatises of the Yellow Emperor
Yates, Robin D. S., Five Lost Classics: Tao, Huang-Lao, and Yin-Yang in Hun China     

Motion-detecting mechanisms: Dual input devices?

Displacement thresholds for luminance step edges were measured for a wide range of contrasts and mean luminances. Thresholds for extended edges (longer than about 0.5°) are determined not by contrast but rather by the amplitude (L_max-L_min) of the luminance change produced by the displacement. Arguing from the standpoint of the Marr-Ullman model of movement detection, we had expected that thresholds might be jointly determined by both contrast and amplitude. Using a range of edges of different lengths, we found that differential effects of luminance and contrast can be revealed: for short edges (less than about 0.5°) thresholds are influenced by both amplitude and contrast, while for more extensive edges only amplitude has an influence. The results are consistent with the properties of a mechanism that has two separate inputs, one from a spatial operator that is contrast-dependent and one from a temporal operator that is amplitude-dependent. The spatial operator is markedly sensitive to changes in edge extent, the temporal operator much less so. The output of the spatial operator saturates early as a function of contrast.     

Modelling visual detection: Luminance response non-linearity and internal noise

Two experiments that investigate the effect of various display factors on the detectability of a thin line signal in random visual noise are described. Three statistical decision models are described, together with their ability to account for the results. The first is an “ideal detector” model, the second an “energy integrator” model, and the third a model based upon the operation of retinal ganglion cells which incorporates a gain control mechanism. The ideal detector model fails to give a good account of human performance, whereas the other two models provide a good fit to the data. The digital Laplacian with gain control model has the slight advantage over the energy integrating model in being able to account for a small superiority in the detection of dark as opposed to bright signals. Finally, both models require the inclusion of an estimate of the internal noise of the human visual system to account for the pattern of performance observed under changing conditions of display contrast.