The Effects of Emotions and Distraction on Attention During a Perceptual Task

According to the broaden-and-build theory of positive emotions, positive emotions broaden while negative emotions narrow thought-action repertoires. These processes reflect changes in attentional scope, which is the focus of this research. The present study tested the hypothesis that participants in negative mood would be better able to focus on a target figure and separate it from its context in a perceptual task, and would also be better able to focus on the task amid a distracting environment than participants in a positive mood. An undergraduate sample of 77 participants watched video clips selected to induce either fear or amusement, and completed an Embedded Figures Test either in a quiet setting or in a noisy setting. A higher-order ANOVA revealed that Mood had a marginally significant effect on task performance, F(1, 73) = 3.94, p = .051, and that Distraction, F(1, 72) = 4.61, p = .035 and the Mood x Distraction interaction, F(1, 73) = 9.12, p = .003 did significantly affect task performance. However, contrary to the hypothesis, the effect of the distraction manipulation was greater for participants in a negative mood than it was for participants in a positive mood. The author suggests future directions to clarify the relationship between emotions, attentional scope, and susceptibility to environmental distraction.

Global Search for Minimum Energy (H2O)n Clusters, n = 3−5

The Gaussian-3 (G3) model chemistry method has been used to calculate the relative ΔG° values for all possible conformers of neutral clusters of water, (H2O)n, where n = 3−5. A complete 12-fold conformational search around each hydrogen bond produced 144, 1728, and 20 736 initial starting structures of the water trimer, tetramer, and pentamer. These structures were optimized with PM3, followed by HF/6-31G* optimization, and then with the G3 model chemistry. Only two trimers are present on the G3 potential energy hypersurface. We identified 5 tetramers and 10 pentamers on the potential energy and free-energy hypersurfaces at 298 K. None of these 17 structures were linear; all linear starting models folded into cyclic or three-dimensional structures. The cyclic pentamer is the most stable isomer at 298 K. On the basis of this and previous studies, we expect the cyclic tetramers and pentamers to be the most significant cyclic water clusters in the atmosphere.