Judging trustworthiness from faces: Emotion cues modulate trustworthiness judgments in young children

By adulthood, people judge trustworthiness from appearances rapidly and reliably. However, we know little about these judgments in children. This novel study investigates the developmental trajectory of explicit trust judgments from faces, and the contribution made by emotion cues across age groups. Five‐, 7‐, 10‐year‐olds, and adults rated the trustworthiness of trustworthy and untrustworthy faces with neutral expressions. The same participants also rated faces displaying overt happy and angry expressions, allowing us to investigate whether emotion cues modulate trustworthiness judgments similarly in children and adults. Results revealed that the ability to evaluate the trustworthiness of faces emerges in childhood, but may not be adult like until 10 years of age. Moreover, we show that emotion cues modulate trust judgments in young children, as well as adults. Anger cues diminished the appearance of trustworthiness for participants from 5 years of age and happy cues increased it, although this effect did not consistently emerge until later in childhood, that is, 10 years of age. These associations also extended to more subtle emotion cues present in neutral faces. Our results indicate that young children are sensitive to facial trustworthiness, and suggest that similar expression cues modulate these judgments in children and adults.     

Priming effects for affective vs. neutral faces

Affective and Neutral Tasks (faces with negative or neutral content, with different lighting and orientation) requiring reaction time judgments of poser identity were administered to 32 participants. Speed and accuracy were better for the Affective than Neutral Task, consistent with literature suggesting facilitation of performance by affective content. Priming effects were significant for the Affective but not Neutral Task. An Explicit Post-Test indicated no conscious knowledge of the stimulus frequency that was associated with performance facilitation. Faster performance by female vs. male participants, and differential speeds and susceptibility to priming of different emotions were also found. Anger and shock were responded to most rapidly and accurately in several conditions, showed no gender differences, and showed significant priming for both RT and accuracy. Fear and pain were responded to least accurately, were associated with faster female than male reaction time, and the accuracy data showed a kind of reverse priming.     

Priming effects for affective vs. neutral faces

Affective and Neutral Tasks (faces with negative or neutral content, with different lighting and orientation) requiring reaction time judgments of poser identity were administered to 32 participants. Speed and accuracy were better for the Affective than Neutral Task, consistent with literature suggesting facilitation of performance by affective content. Priming effects were significant for the Affective but not Neutral Task. An Explicit Post-Test indicated no conscious knowledge of the stimulus frequency that was associated with performance facilitation. Faster performance by female vs. male participants, and differential speeds and susceptibility to priming of different emotions were also found. Anger and shock were responded to most rapidly and accurately in several conditions, showed no gender differences, and showed significant priming for both RT and accuracy. Fear and pain were responded to least accurately, were associated with faster female than male reaction time, and the accuracy data showed a kind of reverse priming.     

Visual consciousness of faces in the attentional blink: Knowledge-based effects of trustworthiness dominate over appearance-based impressions

How we perceive and evaluate other persons depends on appearance-based impressions as well as top-down information such as knowledge about someone’s character. To date, little is known about how these two sources of information affect the conscious perception of faces, about their relative contributions and possible interactions. Here, we directly compare how social-affective knowledge and visual cues of trustworthiness impact the access of faces to visual consciousness. Low- and average-trustworthy looking faces were associated with neutral or negative information about a person’s social behavior. Trustworthiness and facial expression ratings showed robust and independent effects of both sources of information during evaluations. Under conditions of reduced attention in an attentional blink task, prioritized detection of faces associated with negative as compared to neutral person knowledge was observed, whereas facial trustworthiness did not affect detection. Thus, while both factors influenced conscious perception and evaluation, only person knowledge impacted the access to consciousness.     

Perceived trustworthiness of faces drives trust behaviour in children

Facial appearances can powerfully influence adults' trust behaviour, despite limited evidence that these cues constitute honest signals of trustworthiness. It is not clear, however, whether the same is also true for children. The current study investigated whether, like adults, 5‐year‐olds and 10‐year‐olds are more likely to place their trust in partners that look trustworthy than those that look untrustworthy. A second, closely related question was whether children also explicitly value the information from face cues when making trust decisions. We investigated these questions using Token Quest: an economic trust game that gave participants the opportunity to make investments with a series of partners who might (or might not) repay their trust with large returns. These interactions occurred under different conditions, including one in which participants were shown the face of each partner and another in which they could ‘purchase’ access to faces with a portion of their investment capital. Results indicated that, like adults, 10‐year‐old children selectively placed their trust in those partners they perceived as looking trustworthy and many were willing to ‘pay’ to purchase access to these face cues during the trust game. We observed a similar profile of trust behaviour in 5‐year‐olds, with no significant group difference in the impact of face cues on behaviour across the three age groups. Together, these findings indicate that the influence of face cues on trust behaviour emerges early, and highlight a capacity for sophisticated social cognition in young children.     

Trust and distrust: the perception of trustworthiness of faces in psychopathic and non-psychopathic offenders

Psychopathy is a disorder linked to impairments in social cognition. Individuals with psychopathy and comparison individuals, as defined by the Hare Psychopathy Checklist Revised (Hare, 1991), completed a task requiring complex social judgments. Participants viewed a series of male faces, and made judgments concerning how trustworthy they considered the person pictured to be and the degree to which each face was displaying specific emotions. Judgments of trustworthiness did not differ between the individuals with psychopathy and the comparison individuals. Trustworthiness judgments of the faces negatively correlated with, in particular, ratings of anger in the faces for both groups of participants. The data are discussed with reference to the neural systems, including the amygdala, considered to be involved in the mediation of task performance and also neuro-cognitive models of psychopathy.     

Preferences as expectation-driven inferences: effects of affective expectations on affective experience

Presents a model arguing that affect and emotion are often formed in an expectation-driven fashion. A pilot study and 2 experiments manipulated undergraduate Ss' affective expectations (e.g., how funny they expected a set of cartoons to be) and whether Ss' expectations were confirmed (e.g., whether the cartoons really were funny). When the value of a stimulus was consistent with an affective expectation, people formed evaluations relatively quickly. Even when the value of a stimulus was discrepant from an affective expectation, people sometimes assimilated the value of the stimulus to their expectations. Other times, such as when making a more fine-grained evaluation of the cartoons, people noticed that they were discrepant from their affective expectations. Under these conditions, people appeared to have more difficulty forming preferences. They took longer to evaluate and spent more time thinking about the cartoons.     

Telling faces together: Learning new faces through exposure to multiple instances

We are usually able to recognize novel instances of familiar faces with little difficulty, yet recognition of unfamiliar faces can be dramatically impaired by natural within-person variability in appearance. In a card-sorting task for facial identity, different photos of the same unfamiliar face are often seen as different people. Here we report two card-sorting experiments in which we manipulate whether participants know the number of identities present. Without constraints, participants sort faces into many identities. However, when told the number of identities present, they are highly accurate. This minimal contextual information appears to support viewers in “telling faces together”. In Experiment 2 we show that exposure to within-person variability in the sorting task improves performance in a subsequent face-matching task. This appears to offer a fast route to learning generalizable representations of new faces.     

Two faces of (dis)similarity in affective judgments of persons: contrast or assimilation effects revealed by morphs

The authors investigated the role of dissimilarity on context effects in person perception. Most research predicts similar people to be similarly evaluated and different people to be contrasted with each other. However, some research suggests that similarity may enhance comparison and contrast. To explain these opposite effects, the authors argue that dissimilarity may influence 2 different processes with opposite consequences. Dissimilarity may decrease common categorization and thus the likelihood of comparison, resulting in reduced contrast, whereas during comparison itself dissimilarity may increase the perceived dissimilarity of features and thereby increase contrast. To investigate this, the authors conducted 3 studies in which they manipulated dissimilarity by inserting morphs that were related or unrelated to the context and target faces before judgments were made. The results indicate that dissimilarity may affect the likelihood and the outcome of comparison, with contrasting consequences.     

Recognition advantage of happy faces in extrafoveal vision: Featural and affective processing

Happy, surprised, disgusted, angry, sad, fearful, and neutral facial expressions were presented extrafoveally (2.5° away from fixation) for 150 ms, followed by a probe word for recognition (Experiment 1) or a probe scene for affective valence evaluation (Experiment 2). Eye movements were recorded and gaze-contingent masking prevented foveal viewing of the faces. Results showed that (a) happy expressions were recognized faster than others in the absence of fixations on the faces, (b) the same pattern emerged when the faces were presented upright or upside-down, (c) happy prime faces facilitated the affective evaluation of emotionally congruent probe scenes, and (d) such priming effects occurred at 750 but not at 250 ms prime–probe stimulus–onset asynchrony. This reveals an advantage in the recognition of happy faces outside of overt visual attention, and suggests that this recognition advantage relies initially on featural processing and involves processing of positive affect at a later stage.     

Understanding evaluation of faces on social dimensions

People reliably and automatically make personality inferences from facial appearance despite little evidence for their accuracy. Although such inferences are highly inter-correlated, research has traditionally focused on studying specific traits such as trustworthiness. We advocate an alternative, data-driven approach to identify and model the structure of face evaluation. Initial findings indicate that specific trait inferences can be represented within a 2D space defined by valence/trustworthiness and power/dominance evaluation of faces. Inferences along these dimensions are based on similarity to expressions signaling approach or avoidance behavior and features signaling physical strength, respectively, indicating that trait inferences from faces originate in functionally adaptive mechanisms. We conclude with a discussion of the potential role of the amygdala in face evaluation.     

Visual search of emotional faces: The role of affective content and featural distinctiveness

We investigated the source of the visual search advantage of some emotional facial expressions. An emotional face target (happy, surprised, disgusted, fearful, angry, or sad) was presented in an array of neutral faces. A faster detection was found for happy targets, with angry and, especially, sad targets being detected more poorly. Physical image properties (e.g., luminance) were ruled out as a potential source of these differences in visual search. In contrast, the search advantage is partly due to the facilitated processing of affective content, as shown by an emotion identification task. Happy expressions were identified faster than the other expressions and were less likely to be confounded with neutral faces, whereas misjudgements occurred more often for angry and sad expressions. Nevertheless, the distinctiveness of some local features (e.g., teeth) that are consistently associated with emotional expressions plays the strongest role in the search advantage pattern. When the contribution of these features to visual search was factored out statistically, the advantage disappeared.     

Angry faces are more resistant to forgetting than are happy faces: directed forgetting effects on the identity of emotional faces

Using the item-method directed forgetting paradigm (i.e. intentionally forgetting specified information), we examined directed forgetting of facial identity as a function of facial expression and the sex of the expresser and perceiver. Participants were presented with happy and angry male and female faces cued for either forgetting or remembering, and were then asked to recognise previously studied faces from among a series of neutral faces. For each recognised test face, participants also recalled the face’s previously displayed emotional expression. We found that angry faces were more resistant to forgetting than were happy faces. Furthermore, angry expressions on male faces and happy expressions on female faces were recognised and recalled better than vice versa. Signal detection analyses revealed that male faces gave rise to a greater sensitivity than female faces did, and male participants, but not female participants, showed greater sensitivity to male faces than to female faces. Several theoretical implications are discussed.     

Directed forgetting: differential effects on typical and distinctive faces

Directed forgetting (DF) occurs when stimuli presented during the study phase are followed by "forget" and "remember" cues. On a subsequent memory test, poor memory is observed for stimuli followed by the forget cues, compared to stimuli followed by the remember cues. Although DF is most commonly observed with verbal tasks, the present study extended intentional forgetting research for nonverbal stimuli and examined whether faces were susceptible to DF. Results confirmed that the presentation of a forget cue significantly reduced recognition for faces, as compared to faces followed by a remember cue. Additionally, a well-established finding in face recognition is that distinctive faces are better remembered than typical faces, and Experiment 2 assessed whether face appearance influenced the degree of DF. Results indicate that the DF effect observed in Experiment 1 was replicated in Experiment 2 and that the effect was more pronounced for those faces that were typical in appearance.     

The effect of behavioral response on affective evaluation

In the present research we investigated how action influences affective evaluation. In three experiments, participants conducted a sequence of go/no-go tasks, then evaluated the pleasantness of a novel shape. The results of Experiments 1 and 2 show that participants evaluated the shapes that appeared in the go trials more positively than the shapes that appeared in the no-go trials. In Experiment 3, the go/no-go task was conducted without the to-be-evaluated shapes present in the display. The results show that the shape stimuli following the go trials were evaluated more positively than the shape stimuli following the no-go trials, even when the shapes were not directly associated with the go/no-go task. Based on the present study, we suggest that activating or inhibiting a motoric action may play a critical role in modifying one's affective evaluation. Additionally, the present results suggest that effortful and non-default responses can negatively modulate affective evaluation by taxing an individual's cognitive load. Furthermore, we argue that individuals can potentially control their affective states through behavioral activation and inhibition.     

The effects of source trustworthiness and inference type on human belief revision

We investigated whether people revise their beliefs as a function of inference type or source trustworthiness. By doing so we aimed to find out if belief revision is better explained by mental model theory (Johnson-Laird & Byrne, 2002 Johnson-Laird, P. N. and Byrne, R. M. J. 2002. Conditionals: A theory of meaning, pragmatics, and inference. Psychological Review, 109: 211–228. [Crossref], [Web of Science ®] , [Google Scholar]) or by a conditional probability view (Evans, Handley, & Over, 2003 Over, D. E. and Evans, J. St. B. T. 2003. The probability of conditionals: The psychological evidence. Mind & Language, 18: 340–358. [Crossref], [Web of Science ®] , [Google Scholar]; Oaksford & Chater, 2001 Oaksford, M. and Chater, N. 2001. The probabilistic approach to human reasoning. Trends in Cognitive Science, 5: 349–357. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). We used modified modes ponens (MP) and modus tollens (MT) problems in which the first two premises were uttered by persons with varying degrees of trustworthiness. A third statement was presented as a fact and established inconsistency in the set of propositions. The participants' task was to indicate which of the first two premises they believed more after receiving the fact. We found that the belief in the conditional premise dropped significantly when this premise was stated by a low- rather than a high-trustworthy source. Moreover we found that the conditional premise was believed more in MT than in MP problems. Both findings are best explained by the conditional probability hypothesis (e.g., Evans et al., 2003 Evans, J. St. B. T., Handley, S. J. and Over, D. E. 2003. Conditionals and conditional probability. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29, : 321–335. [Crossref] , [Google Scholar]).     

Strength of visual percept generated by famous faces perceived without awareness: effects of affective valence, response latency, and visual field

Participants who were unable to detect familiarity from masked 17 ms faces (Stone and Valentine, 2004 and Stone and Valentine, in press-b) did report a vague, partial visual percept. Two experiments investigated the relative strength of the visual percept generated by famous and unfamiliar faces, using masked 17 ms exposure. Each trial presented simultaneously a famous and an unfamiliar face, one face in LVF and the other in RVF. In one task, participants responded according to which of the faces generated the stronger visual percept, and in the other task, they attempted an explicit familiarity decision. The relative strength of the visual percept of the famous face compared to the unfamiliar face was moderated by response latency and participants' attitude towards the famous person. There was also an interaction of visual field with response latency, suggesting that the right hemisphere can generate a visual percept differentiating famous from unfamiliar faces more rapidly than the left hemisphere. Participants were at chance in the explicit familiarity decision, confirming the absence of awareness of facial familiarity.     

Spacing effects on the memory for faces

25 undergraduate women studied 12 stimulus pictures of female faces successively presented in spaced or massed conditions and made affective judgments for the pictures along a dimension of like to dislike. One week after the exposure (study) period, subjects were given an identification test comprised of photographs of the same female faces with different expressions. Analysis showed that the pictures presented in the spaced condition were more frequently and accurately identified than those presented under the massed condition and that affective judgment was unrelated to conditions of presentation.     

Mind the gap: interhemispheric communication about emotional faces

This study tested the hypothesis that interhemispheric communication about emotional stimuli is influenced by situational factors that alter emotional relevance. Under evaluative or nonevaluative conditions, participants matched angry and happy faces within a single visual field or across opposite visual fields. An overall across-field advantage (AFA) reflected the benefit of sharing information between the hemispheres. The AFA was greater for angry than for happy faces in the evaluation condition but did not differ for angry and happy faces in the no-evaluation condition. Examination of individual differences indicated that high trait evaluation levels of worry were associated with poorer interhemispheric communication of angry faces, supporting a threat-avoidance conception of worry. Thus, both situational factors and individual differences affected interhemispheric communication about emotional faces.