The effect of sad facial expressions on weight judgment

Although the body weight evaluation (e.g., normal or overweight) of others relies on perceptual impressions, it also can be influenced by other psychosocial factors. In this study, we explored the effect of task-irrelevant emotional facial expressions on judgments of body weight and the relationship between emotion-induced weight judgment bias and other psychosocial variables including attitudes towards obese person. Forty-four participants were asked to quickly make binary body weight decisions for 960 randomized sad and neutral faces of varying weight levels presented on a computer screen. The results showed that sad facial expressions systematically decreased the decision threshold of overweight judgments for male faces. This perceptual decision bias by emotional expressions was positively correlated with the belief that being overweight is not under the control of obese persons. Our results provide experimental evidence that task-irrelevant emotional expressions can systematically change the decision threshold for weight judgments, demonstrating that sad expressions can make faces appear more overweight than they would otherwise be judged

Be Happy Not Sad for Your Youth: The Effect of Emotional Expression on Age Perception - Fig 1

<p><b>A. Experimental stimuli used for the age judgment task.</b> All facial stimuli were computer-generated and no actual faces were used in our study. The emotional expression (sad, neutral, or happy) and age of the facial stimulus were manipulated by using morphing software. Faces of all emotional expressions have eight equivalent age gradients ranging from 30 years old to 65 years old increasing by 5-year increments. <b>B. Sample screen of the young-old judgment task.</b> Participants were asked to make an age decision in two-alternative forced-choice (either young or old) procedures. The positions of young and old labels were counterbalanced across participants. <b>C. Psychometric curves (Naka-Rushton contrast response model).</b> X-axis represents stimulus intensity level and Y-axis represents response probability. In our experiments, the stimulus intensity represents the incremental increase of age of morphed faces (30 to 65 years old) and the response represents the proportion of old decisions in a forced two-alternative choice task. The <i>C</i>_<i>50</i> or <i>PSE</i> (Point of Subjective Equality) parameter indicates the perceptual decision threshold. A leftward shift of the psychometric curve (see arrow) would constitute evidence for a decreased perceptual threshold for condition 1 compared to condition 2.</p

Means and standard deviations of psychometric curve fit parameters.

<p>Means and standard deviations of psychometric curve fit parameters.</p

Means and standard deviations of the proportion of old decisions.

<p>Means and standard deviations of the proportion of old decisions.</p

Means and standard deviations of response times in millisecond.

<p>Means and standard deviations of response times in millisecond.</p

Novel metabolic interactions and environmental conditions mediate the boreal peatmoss-cyanobacteria mutualism.

Interactions between Sphagnum (peat moss) and cyanobacteria play critical roles in terrestrial carbon and nitrogen cycling processes. Knowledge of the metabolites exchanged, the physiological processes involved, and the environmental conditions allowing the formation of symbiosis is important for a better understanding of the mechanisms underlying these interactions. In this study, we used a cross-feeding approach with spatially resolved metabolite profiling and metatranscriptomics to characterize the symbiosis between Sphagnum and Nostoc cyanobacteria. A pH gradient study revealed that the Sphagnum-Nostoc symbiosis was driven by pH, with mutualism occurring only at low pH. Metabolic cross-feeding studies along with spatially resolved matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) identified trehalose as the main carbohydrate source released by Sphagnum, which were depleted by Nostoc along with sulfur-containing choline-O-sulfate, taurine and sulfoacetate. In exchange, Nostoc increased exudation of purines and amino acids. Metatranscriptome analysis indicated that Sphagnum host defense was downregulated when in direct contact with the Nostoc symbiont, but not as a result of chemical contact alone. The observations in this study elucidated environmental, metabolic, and physiological underpinnings of the widespread plant-cyanobacterial symbioses with important implications for predicting carbon and nitrogen cycling in peatland ecosystems as well as the basis of general host-microbe interactions

Microbial Ecology of the Dark Ocean above, at, and below the Seafloor†

Summary: The majority of life on Earth—notably, microbial life—occurs in places that do not receive sunlight, with the habitats of the oceans being the largest of these reservoirs. Sunlight penetrates only a few tens to hundreds of meters into the ocean, resulting in large-scale microbial ecosystems that function in the dark. Our knowledge of microbial processes in the dark ocean—the aphotic pelagic ocean, sediments, oceanic crust, hydrothermal vents, etc.—has increased substantially in recent decades. Studies that try to decipher the activity of microorganisms in the dark ocean, where we cannot easily observe them, are yielding paradigm-shifting discoveries that are fundamentally changing our understanding of the role of the dark ocean in the global Earth system and its biogeochemical cycles. New generations of researchers and experimental tools have emerged, in the last decade in particular, owing to dedicated research programs to explore the dark ocean biosphere. This review focuses on our current understanding of microbiology in the dark ocean, outlining salient features of various habitats and discussing known and still unexplored types of microbial metabolism and their consequences in global biogeochemical cycling. We also focus on patterns of microbial diversity in the dark ocean and on processes and communities that are characteristic of the different habitats