One of science's greatest intellects examines how people and animals display fear, anger, and pleasure. Darwin based this 1872 study on his personal observations, which anticipated later findings in neuroscience. Abounding in anecdotes and literary quotations, the book is illustrated with 21 figures and seven photographic plates. Its direct approach, accessible to professionals and amateurs alike, continues to inspire and inform modern research in psychology.

Behavioral scientists routinely publish broad claims about human psychology and behavior in the world's top journals based on samples drawn entirely from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) societies. Researchers – often implicitly – assume that either there is little variation across human populations, or that these “standard subjects” are as representative of the species as any other population. Are these assumptions justified? Here, our review of the comparative database from across the behavioral sciences suggests both that there is (...) substantial variability in experimental results across populations and that WEIRD subjects are particularly unusual compared with the rest of the species – frequent outliers. The domains reviewed include visual perception, fairness, cooperation, spatial reasoning, categorization and inferential induction, moral reasoning, reasoning styles, self-concepts and related motivations, and the heritability of IQ. The findings suggest that members of WEIRD societies, including young children, are among the least representative populations one could find for generalizing about humans. Many of these findings involve domains that are associated with fundamental aspects of psychology, motivation, and behavior – hence, there are no obviousa priorigrounds for claiming that a particular behavioral phenomenon is universal based on sampling from a single subpopulation. Overall, these empirical patterns suggests that we need to be less cavalier in addressing questions ofhumannature on the basis of data drawn from this particularly thin, and rather unusual, slice of humanity. We close by proposing ways to structurally re-organize the behavioral sciences to best tackle these challenges. (shrink)

Young, middle-aged, and older raters (N=154) evaluated 1,026 prototypical facial poses of neutrality, happiness, anger, disgust, fear, and sadness stemming from 171 young, middle-aged, and older posers. The majority of poses were rated as multi-faceted, that is, to comprise several expressions of varying intensities. Consistent with the notion of age-related increases in negativity–avoidance/positivity effects, crossed-random effects analyses showed an age-related decrease in the attributions of negative, but not positive and neutral, target expressions (that the poser intended to show), and an (...) age-related increase in the attributions of positive and neutral, but not negative, non-target expressions (that the posers did not intend to show). Expressions were more difficult to read the older the posers, particularly for male posers. These age-of-poser effects were independent of the valence of the expression, but partly differed across age groups of raters. The study supports the idea of multi-dimensionality and age-dependency of emotion perception. (shrink)

Many research fields concerned with the processing of information contained in human faces would benefit from face stimulus sets in which specific facial characteristics are systematically varied while other important picture characteristics are kept constant. Specifically, a face database in which displayed expressions, gaze direction, and head orientation are parametrically varied in a complete factorial design would be highly useful in many research domains. Furthermore, these stimuli should be standardised in several important, technical aspects. The present article presents the freely (...) available Radboud Faces Database offering such a stimulus set, containing both Caucasian adult and children images. This face database is described both procedurally and in terms of content, and a validation study concerning its most important characteristics is presented. In the validation study, all frontal images were rated with respect to the shown facial expression, intensity of expression, clarity of expression, genuineness of expression, attractiveness, and valence. The results show very high recognition of the intended facial expressions. (shrink)

We investigated how age of faces and emotion expressed in faces affect young (n=30) and older (n=20) adults’ visual inspection while viewing faces and judging their expressions. Overall, expression identification was better for young than older faces, suggesting that interpreting expressions in young faces is easier than in older faces, even for older participants. Moreover, there were age-group differences in misattributions of expressions, in that young participants were more likely to label disgusted faces as angry, whereas older adults were more (...) likely to label angry faces as disgusted. In addition to effects of emotion expressed in faces, age of faces affected visual inspection of faces: Both young and older participants spent more time looking at own-age than other-age faces, with longer looking at own-age faces predicting better own-age expression identification. Thus, cues used in expression identification may shift as a function of emotion and age of faces, in interaction with age of participants. (shrink)