Ad van Knippenberg

Presentation and validation of the Radboud Faces Database

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.

Mimicry and Prosocial Behavior

Recent studies have shown that mimicry occurs unintentionally and even among strangers. In the present studies, we investigated the consequences of this automatic phenomenon in order to learn more about the adaptive function it serves. In three studies, we consistently found that mimicry increases pro-social behavior. Participants who had been mimicked were more helpful and generous toward other people than were non-mimicked participants. These beneficial consequences of mimicry were not restricted to behavior directed toward the mimicker, but included behavior directed toward people not directly involved in the mimicry situation. These results suggest that the effects of mimicry are not simply due to increased liking for the mimicker, but are due to increased prosocial orientation in general.

What's in a Name: Implicit Self-Esteem and the Automatic Self

This article explores the links between implicit self-esteem and the automatic self (D. L. Paulhus, 1993). Across 4 studies, name letter evaluations were positively biased, confirming that implicit self-esteem is generally positive (A. G. Greenwald & M. R. Banaji, 1995). Study 1 found that this name letter bias was stable over a 4-week period. Study 2 found that positive bias for name letters and positive bias for birth date numbers were correlated and that both biases became inhibited when participants were induced to respond in a deliberative manner. Studies 3-4 found that implicit self-evaluations corresponded with self-reported self-evaluations, but only when participants were evaluating themselves very quickly (Study 3) or under cognitive load (Study 4). Together, these findings support the notion that implicit self-esteem phenomena are driven by self-evaluations that are activated automatically and without conscious self-reflection.

Mimicry for money: Behavioral consequences of imitation ☆

Two experiments investigated the idea that mimicry leads to pro-social behavior. It was hypothesized that mimicking the verbal behavior of customers would increase the size of tips. In Experiment 1, a waitress either mimicked half her customers by literally repeating their order or did not mimic her customers. It was found that she received significantly larger tips when she mimicked her customers than when she did not. In Experiment 2, in addition to a mimicry- and non-mimicry condition, a baseline condition was included in which the average tip was assessed prior to the experiment. The results indicated that, compared to the baseline, mimicry leads to larger tips. These results demonstrate that mimicry can be advantageous for the imitator because it can make people more generous.

It Takes Two to Mimic: Behavioral Consequences of Self-Construals

The present studies demonstrated the moderation of self-construal orientation on mimicry. Recent research has indicated that an interdependent self-construal is associated with assimilation of the other to the self whereas an independent self-construal is associated with minimizing the influence of others on the self (H. R. Markus & S. Kitayama, 1991; D. Stapel & W. Koomen, 2001). Therefore, the authors hypothesized that an interdependent self-construal would be associated with more mimicry than an independent self-construal. When self-construal orientations were experimentally primed, as in Studies 1 and 2, independent self-construals produced less nonconscious mimicry than interdependent self-construals. When self-construals were examined as cultural differences with either a chronically dominant independent (Americans) or interdependent (Japanese) construal of the self, these results were replicated.

Remembering Can Cause Inhibition: Retrieval-Induced Inhibition as Cue Independent Process

Previous experiments have mostly relied on recall as a dependent measure to assess whether retrieval of information from memory causes inhibition of related information. This study aimed to measure this inhibition in a more direct way. In Experiment 1, it was shown that repeated retrieval of exemplars from a category resulted in longer recognition latencies to nonretrieved exemplars from that same category, compared with recognition latencies to control exemplars. Experiment 2 obtained the same pattern of results using a lexical decision task. This was the 1st time that retrieval-induced forgetting was demonstrated on an implicit test of memory. To exclude noninhibitory explanations of the data, the exemplars were presented in both experiments without their categories as cues.

Derogation and distancing as terror management strategies: the moderating role of need for closure and permeability of group boundaries.

Previous research has revealed that when individuals are confronted with criticism of a personally relevant group, mortality salience can lead to either derogation of the source of criticism or distancing from the group. In this article, the authors investigated closure as a potential moderator of these reactions. In Study 1, mortality salience led to greater derogation of a critic of a relevant group among high-need-for-closure participants but led to distancing from the group among low need-for-closure participants. Study 2 showed that when a relevant group was criticized, mortality salience led to greater derogation among participants who were led to believe that the boundaries of that group were impermeable but led to greater distancing among participants who were made aware of the permeable nature of the group boundaries. These findings demonstrate that closure of group membership moderates reactions to criticism of a personally relevant group after mortality salience.

The Role of Facial Mimicry in the Recognition of Affect

How do you decide whether the emotion expressed on another person’s face is positive or negative? Emotions may be perceived via two routes. The longer (slower) route involves matching visual input with stored knowledge about emotions. The shorter (faster) route involves empathic emotions that serve as proprioceptive cues in emotion recognition. In line with embodiedcognition theory (Barsalou, Niedenthal, Barbey, & Ruppert, 2003), we propose that mimicry may result in faster emotion recognition because it facilitates use of the shorter route. To test this idea, we studied the effect of constraining mimicry on speed of emotion recognition. Consistent with the present view, perceivers spontaneously mimic facial expressions of emotions (Dimberg, 1990), and their own experienced emotions are affected accordingly (Stel, Van Baaren, & Vonk, in press). Freezing the face reduces the experience of emotional empathy (Stel et al., in press). Blairy, Herrera, and Hess (1999) failed to demonstrate a link between mimicry and accuracy of emotion recognition. However, we propose that mimicry facilitates the short route of one’s access to others’ emotions, which means that mimicry should affect speed, but not accuracy, of emotion recognition. We hypothesized that participants will recognize a briefly exposed facial expression of emotion more slowly when they are unable to mimic facial expressions than when they are free to mimic the expression. Moreover, we expect this effect to be more pronounced for women than for men: Women are more facially expressive than are men (LaFrance & Hecht, 2000), and facial feedback may be more important in emotion-related processing for women than it is for men. METHOD

From repetition to conviction: Attitude accessibility as a determinant of attitude certainty ☆

The present experiment investigated the influence of attitude accessibility on several meta-attitudinal strength measures. It was predicted that certainty and perceived likelihood of change, i.e., commitment-related attributes of attitude strength, are influenced by changes in attitude accessibility, while no effects were expected for importance and perceived centrality to values and the self, i.e., centrality-related attributes. Accessibility was manipulated by having participants express their attitudes either repeatedly or only once. As hypothesized, accessibility and measures of commitment were enhanced after repeated expression compared to single expression. Furthermore, mediation analyses supported the idea that subjective commitment may be inferred from the ease of attitude retrieval. Centrality-related attributes were found to be unaffected by the accessibility manipulation. The results are discussed in the light of a multi-dimensional structure of attitude strength and antecedent processes of meta-cognitive attributes of strength.

Humor in advertisements enhances product liking by mere association.

Humor in advertising is known to enhance product liking, but this attitude change is often considered nonpredictive of product choice. Previous research relied exclusively on explicit self-report measures to assess attitudes and purchase intentions. The present research shows that unobtrusive association of a product with humor can affect persuasion through implicit attitude change. Participants viewed humorous and nonhumorous cartoons in a mock-up magazine. One of two products was consistently presented in the vicinity of the humorous cartoons, whereas the other product was consistently presented in the vicinity of the nonhumorous cartoons. The results of an evaluative priming task showed enhanced evaluations of products paired with humor (Experiment 1, 2, and 3). Furthermore, these enhanced evaluations mediated the relation between association with humor and product choice (Experiment 2 and 3). Paradoxically, products paired with humor were also less recognized than the control products (Experiments 2 and 3). In summary, the present research demonstrates that mere association with humor enhances product evaluations and product choice in a way that is dissociated from the accessibility of the product in memory.