Psychological Science

We investigated the relationship of implicit racial prejudice to discriminatory behavior. White university students chose the best of three applicants (two were White and one was Black) for a prestigious teaching fellowship. They then completed the Implicit Association Test (IAT), a measure of implicit racial bias. Three weeks later, participants completed a second implicit measure of racial bias by viewing photos of Whites and Blacks while facial electromyography (EMG) was recorded from sites corresponding to the muscles used in smiling and frowning. Analyses revealed that bias in cheek EMG activity was related to the race of the chosen applicant, whereas bias on the IAT was not. Motivations to control prejudiced reactions were not related to EMG activity or the race of the applicant chosen, but were related to IAT bias. The findings indicate that facial EMG can be used as an implicit measure of prejudice related to discrimination.

It has become almost a maxim that “talking through” a problem is advantageous. Contrary to this wisdom, studies from numerous domains have demonstrated that describing one's thought processes or analyzing a judgment may, in some circumstances, actually impair performance. The two experiments reported here built upon prior work by examining the effect of verbalization on the retrieval of analogies. Participants read a series of 16 short stories. Later, they were presented with 8 test stories and indicated whether these stories were analogies of the stories they had read previously. Each test story shared the same deep structure with one prior story and only surface characteristics with another prior story. Half of the participants completed the test while thinking aloud, and half did not think aloud. In both experiments, participants who thought aloud were more likely to retrieve surface matches and less likely to retrieve true analogies than participants who did not verbalize their thoughts during the test.

Several theories of the neural correlates of consciousness assume that there is a continuum of perception, associated with a gradual change in the intensity of brain activation. But some models, considering reverberation of neural activity as necessary for conscious perception, predict a sharp nonlinear transition between unconscious and conscious processing. We asked participants to evaluate the visibility of target words on a continuous scale during the attentional blink, which is known to impede explicit reports. Participants used this continuous scale in an all-or-none fashion: Targets presented during the blink were either identified as well as targets presented outside the blink period or not detected at all. We suggest that a stochastic nonlinear bifurcation in neural activity underlies the all-or-none perception observed during the attentional blink.

New learning often interferes with the production of older, previously learned responses. However, the original responses usually appear to spontaneously recover and regain their dominance after a delay. This article takes a new approach to questions of interference and recovery by examining performance on immediate and delayed tests using direct or indirect instructions. Direct instructions asked participants to deliberately retrieve the original responses, and indirect instructions allowed them to respond on a more automatic basis, using whatever response came to mind first. Results suggest that interference and recovery may have their largest effects via relatively automatic influences on memory, such as the accessibility of new versus original information. This finding adds a new perspective to classic theories of interference and recovery, and may also inform current understanding of performance in populations (e.g., older adults) that often rely predominantly on automatic memory processing.

Sexual arousal is category-specific in men; heterosexual men are more aroused by female than by male sexual stimuli, whereas homosexual men show the opposite pattern. There is reason to believe that female sexual arousal is organized differently. We assessed genital and subjective sexual arousal to male and female sexual stimuli in women, men, and postoperative male-to-female transsexuals. In contrast to men, women showed little category specificity on either the genital or the subjective measure. Both heterosexual and homosexual women experienced strong genital arousal to both male and female sexual stimuli. Transsexuals showed a category-specific pattern, demonstrating that category specificity can be detected in the neovagina using a photoplethysmographic measure of female genital sexual arousal. In a second study, we showed that our results for females are unlikely to be explained by ascertainment biases. These findings suggest that sexual arousal patterns play fundamentally different roles in male and female sexuality.

In two experiments, we investigated whether people reason differently when they reason about emotional and neutral contents. We gave participants a conditional reasoning task (“If p, then q”) and varied the emotionality of the items used as p and q. Participants were asked to draw inferences based on these statements. In Experiment 1, we compared statements including preexisting emotional and neutral words. In Experiment 2, we experimentally manipulated the emotionality of initially neutral words using classical conditioning. In both experiments, emotionality affected participants' responses. They were more likely to draw invalid inferences in response to emotional compared with neutral statements.

Examining the receptive fields of brain signals can elucidate how information impinging on the former modulates the latter. We applied this time-honored approach in early vision to the higher-level brain processes underlying face categorizations. Electroencephalograms in response to face-information samples were recorded while observers resolved two different categorizations (gender, expressive or not). Using a method with low bias and low variance, we compared, in a common space of information states, the information determining behavior (accuracy and reaction time) with the information that modulates emergent brain signals associated with early face encoding and later category decision. Our results provide a time line for face processing in which selective attention to diagnostic information for categorizing stimuli (the eyes and their second-order relationships in gender categorization; the mouth in expressive-or-not categorization) correlates with late electrophysiological (P300) activity, whereas early face-sensitive occipitotemporal (N170) activity is mainly driven by the contralateral eye, irrespective of the categorization task.

Unlike most objects, faces are processed holistically: They are processed as a whole rather than as a collection of independent features. We examined the role of early visual experience in the development of this type of processing of faces by using the composite-face task, a measure of holistic processing, to test patients deprived of visual experience during infancy. Visually normal control subjects showed the expected composite-face effect: They had difficulty perceiving that the top halves of two faces were the same when the top halves were aligned with different bottom halves. Performance improved when holistic processing was disrupted by misaligning the top and bottom halves. Deprived patients, in contrast, showed no evidence of holistic processing, and in fact performed significantly better than control subjects when top and bottom halves were aligned. These findings suggest that early visual experience is necessary to set up or maintain the neural substrate that leads to holistic processing of faces.

Perceptual completion consists of bridging the gaps imposed by occlusion, such as perceiving the unity of center-occluded objects. It is unknown at present what developmental mechanisms underlie the emergence of functional perceptual completion in infancy. One current debate centers on the role of visible surface motion. According to a core-principles account, perceptual completion emerges simultaneously with the onset of motion discrimination, the sole determinant of unity percepts in infants. According to a contrasting constructivist account, motion discrimination is but one of several independent inputs to perceptual completion. In the present study, 2-month-old infants were tested for both unity perception and motion discrimination in partial-occlusion displays. Motion discrimination obtained under all conditions, even under circumstances in which infants were unable to perceive completion. Four-month-olds showed marked improvements in perceptual completion, most likely because of improvements in information integration. Taken together, these findings support a constructivist view of early perceptual and cognitive development.

Do genuinely numerical computational abilities exist in infancy? It has recently been argued that previous studies putatively illustrating infants' ability to add and subtract tapped into specialized object-tracking processes that apply only with small numbers. This argument contrasts with the original interpretation that successful performance was achieved via a numerical system for estimating and calculating magnitudes. Here, we report that when continuous variables (such as area and contour length) are controlled, 9-month-old infants successfully add and subtract over numbers of items that exceed object-tracking limits. These results support the theory that infants possess a magnitude-based estimation system for representing numerosities that also supports procedures for numerical computation.

Memory illusions in children of three age groups (5-, 8-, and 11-year-olds) were investigated using a modified version of the Deese-Roediger-McDermott (DRM) procedure. Children from each age group falsely recalled nonpresented items related to the study lists. However, the nature of the intrusions varied across the different groups. The 5-year-olds were more likely to falsely recall words that rhymed with the studied items than to recall unrelated items, whereas the 11-year-olds were more likely to falsely recall words that were semantically related to the list theme than to produce either rhyming or unrelated intrusions. Intrusions made by the 8-year-olds were equally likely to be semantic, rhyming, or unrelated to study items. The results are consistent with the notion of a developmental shift from phonological to semantic associations, leading to qualitatively different memory distortions in children of different ages.

The standard model of labor is one in which individuals trade their time and energy in return for monetary rewards. Building on Fiske's relational theory (1992), we propose that there are two types of markets that determine relationships between effort and payment: monetary and social. We hypothesize that monetary markets are highly sensitive to the magnitude of compensation, whereas social markets are not. This perspective can shed light on the well-established observation that people sometimes expend more effort in exchange for no payment (a social market) than they expend when they receive low payment (a monetary market). Three experiments support these ideas. The experimental evidence also demonstrates that mixed markets (markets that include aspects of both social and monetary markets) more closely resemble monetary than social markets.