Fearful expressions gain preferential access to awareness during continuous flash suppression.

Rapid evaluation of ecologically relevant stimuli may lead to their preferential access to awareness. Continuous flash suppression allows assessment of affective processing under conditions in which stimuli have been rendered invisible due to the strongly suppressive nature of dynamic noise relative to static images. The authors investigated whether fearful expressions emerge from suppression into awareness more quickly than images of neutral or happy expressions. Fearful faces were consistently detected faster than neutral or happy faces. Responses to inverted faces were slower than those to upright faces but showed the same effect of emotional expression, suggesting that some key feature or features in the inverted faces remained salient. When using stimuli solely representing the eyes, a similar bias for detecting fear emerged, implicating the importance of information from the eyes in the preconscious processing of fear expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The look of fear and anger: Facial maturity modulates recognition of fearful and angry expressions.

The current series of studies provide converging evidence that facial expressions of fear and anger may have co-evolved to mimic mature and babyish faces in order to enhance their communicative signal. In Studies 1 and 2, fearful and angry facial expressions were manipulated to have enhanced babyish features (larger eyes) or enhanced mature features (smaller eyes) and in the context of a speeded categorization task in Study 1 and a visual noise paradigm in Study 2, results indicated that larger eyes facilitated the recognition of fearful facial expressions, while smaller eyes facilitated the recognition of angry facial expressions. Study 3 manipulated facial roundness, a stable structure that does not vary systematically with expressions, and found that congruency between maturity and expression (narrow face-anger; round face-fear) facilitated expression recognition accuracy. Results are discussed as representing a broad co-evolutionary relationship between facial maturity and fearful and angry facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognizing masked threat: Fear betrays, but disgust you can trust.

If emotions guide consciousness, people may recognize degraded objects in center view more accurately if they either fear the objects or are disgusted by them. Therefore, we studied whether recognition of spiders and snakes correlates with individual differences in spider fear, snake fear, and disgust sensitivity. Female students performed a recognition task with pictures of spiders, snakes, flowers, and mushrooms as well as blanks. Pictures were backward masked to reduce picture visibility. Signal detection analyses showed that recognition of spiders and snakes was correlated with disgust sensitivity but not with fear of spiders or snakes. Further, spider fear correlated with the tendency to misinterpret blanks as threatening (response bias). These findings suggest that effects on recognition and response biases to emotional pictures vary for different emotions and emotional traits. Whereas fear may induce response biases, disgust may facilitate recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional priming of pop-out in visual search.

When searching for a discrepant target along a simple dimension such as color or shape, repetition of the target feature substantially speeds search, an effect known as feature priming of pop-out (V. Maljkovic and K. Nakayama, 1994). The authors present the first report of emotional priming of pop-out. Participants had to detect the face displaying a discrepant expression of emotion in an array of four face photographs. On each trial, the target when present was either a neutral face among emotional faces (angry in Experiment 1 or happy in Experiment 2), or an emotional face among neutral faces. Target detection was faster when the target displayed the same emotion on successive trials. This effect occurred for angry and for happy faces, not for neutral faces. It was completely abolished when faces were inverted instead of upright, suggesting that emotional categories rather than physical feature properties drive emotional priming of pop-out. The implications of the present findings for theoretical accounts of intertrial priming and for the face-in-the-crowd phenomenon are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual search for facial expressions of emotions: A comparison of dynamic and static faces.

A number of past studies have used the visual search paradigm to examine whether certain aspects of emotional faces are processed preattentively and can thus be used to guide attention. All these studies presented static depictions of facial prototypes. Emotional expressions conveyed by the movement patterns of the face have never been examined for their preattentive effect. The present study presented for the first time dynamic facial expressions in a visual search paradigm. Experiment 1 revealed efficient search for a dynamic angry face among dynamic friendly faces, but inefficient search in a control condition with static faces. Experiments 2 to 4 suggested that this pattern of results is due to a stronger movement signal in the angry than in the friendly face: No (strong) advantage of dynamic over static faces is revealed when the degree of movement is controlled. These results show that dynamic information can be efficiently utilized in visual search for facial expressions. However, these results do not generally support the hypothesis that emotion-specific movement patterns are always preattentively discriminated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional requirements in visual detection and identification: Evidence from the attentional blink.

Perception of the 2nd of 2 targets (T1 and T2) is impaired if the lag between them is short (0–500 ms). The authors used this attentional blink (AB) to index attentional requirements in detection and identification tasks, with or without backward masking of T2, in 2 stimulus domains (line orientation, coherent motion). With masking, the AB occurred because T2 was masked during the attentional dwell time created by T1 processing (Experiments 1, 2, and 3). Without masking, an AB occurred only in identification because during the attentional dwell time. T2 decayed to a level that could support simple detection but not complex identification. However, an AB occurred also in detection if T2 was sufficiently degraded (Experiment 4). The authors drew 2 major conclusions: (a) Attention is required in both identification and detection, and (b) 2 factors contribute to the AB, masking of T2 while attention is focused on T1 and decay of the T2 trace while unattended. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling automatic threat detection: Development of a face-in-the-crowd task.

An angry face is expected to be detected faster than a happy face because of an early, stimulus-driven analysis of threat-related properties. However, it is unclear to what extent results from the visual search approach—the face-in-the-crowd task—mirror this automatic analysis. The paper outlines a model of automatic threat detection that combines the assumption of a neuronal system for threat detection with contemporary theories of visual search. The model served as a guideline for the development of a new face-in-the-crowd task. The development involved three preliminary studies that provided a basis for the selection of angry and happy facial stimuli resembling each other in respect to perceptibility, homogeneity, and intensity. With these stimuli a signal detection version of the search task was designed and tested. For crowds composed of neutral faces, the sensitivity measure d′ proved the expected detection advantage of angry faces compared to happy faces. However, the emotional expression made no difference if a neutral face had to be detected in crowd composed of either angry or happy faces. Results are in line with the assumption of a stimulus-driven shift of attention giving rise to the superior detection of angry target faces. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Fear reactivity to bodily sensations among heavy smokers and nonsmokers.

Individuals who smoke are more likely to experience panic attacks and develop panic disorder than those in the general population. One possible explanation is that smokers may experience a heightened fear response to somatic disturbances. To date, few laboratory studies have tested this hypothesis directly. The present study examined 24 adult heavy smokers (10 females) in 12-hr nicotine withdrawal and 24 adult nonsmokers (12 females) on subjective and physiological reactivity to a 4-min carbon dioxide rebreathing challenge. Results indicate that, despite an attenuated acceleration in respiration during the challenge, smokers experienced a significantly greater increase in self-reported panic symptoms than nonsmokers. In addition, smokers reported significantly greater trait levels of suffocation fear prior to the challenge. Findings are discussed with respect to the role of smoking in panic vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual load alters visual excitability.

Increasing perceptual load reduces the processing of visual stimuli outside the focus of attention, but the mechanism underlying these effects remains unclear. Here we tested an account attributing the effects of perceptual load to modulations of visual cortex excitability. In contrast to stimulus competition accounts, which propose that load should affect simultaneous, but not sequential, stimulus presentations, the visual excitability account makes the novel prediction that load should affect detection sensitivity for both simultaneous and sequential presentations. Participants fixated a stimulus stream, responding to targets defined by either a color (low load) or color and orientation conjunctions (high load). Additionally, detection sensitivity was measured for a peripheral critical stimulus (CS) presented occasionally. Increasing load at fixation reduced sensitivity to the peripheral CSs; this effect was similar regardless of whether CSs were presented simultaneously with central stimuli or during the (otherwise empty) interval between them. Controls ruled out explanations of the results in terms of strategic task prioritization. These findings support a cortical excitability account for perceptual load, challenging stimulus competition accounts. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Visual Awareness and the Detection of Fearful Faces.

A commonly held view is that emotional stimuli are processed independently of awareness. Here, the authors parametrically varied the duration of a fearful face target stimulus that was backward masked by a neutral face. The authors evaluated awareness by characterizing behavioral performance using receiver operating characteristic curves from signal detection theory. Their main finding was that no universal objective awareness threshold exists for fear perception. Although several subjects displayed a behavioral pattern consistent with previous reports (i.e., targets masked at 33 ms), a considerable percentage of their subjects (64%) were capable of reliably detecting 33-ms targets. Their findings suggest that considerable information is available even in briefly presented stimuli (possibly as short as 17 ms) to support masked fear detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional expressions and visual search efficiency: Specificity and effects of anxiety symptoms.

Although facial expressions are thought to vary in their functional impact on perceivers, experimental demonstration of the differential effects of facial expressions on behavior are lacking. In the present study, we examined the effects of exposure to facial expressions on visual search efficiency. Participants (n = 31) searched for a target in a 12 location circle array after exposure to an angry, disgusted, fearful, happy, or neutral facial expression for 100 ms or 500 ms. Consistent with predictions, exposure to a fearful expression prior to visual search resulted in faster target identification compared to exposure to other facial expressions. The effects of other facial expressions on visual search did not differ from each other. The fear facilitating effect on visual search efficiency was observed at 500-ms but not at 100-ms presentations, suggesting a specific temporal course of the facilitation. Subsequent analysis also revealed that individual differences in fear of negative evaluation, trait anxiety, and obsessive–compulsive symptoms possess a differential pattern of association with visual search efficiency. The experimental and clinical implications of these findings are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Impact of Healthy Aging on Awareness and Fear Conditioning.

Fear conditioning has provided a useful model system for studying associative emotional learning, but the impact of healthy aging has gone relatively unexplored. The present study investigated fear conditioning across the adult life span in humans. A delay discrimination task was employed using visual conditioned stimuli and an auditory unconditioned stimulus. Awareness of the reinforcement contingencies was assessed in a postexperimental interview. Compared with young adult participants, middle-aged and older adults displayed reductions in unconditioned responding, discriminant conditioning, and contingency awareness. When awareness and overall arousability were taken into consideration, there were no residual effects of aging on conditioning. These results highlight the importance of considering the influence of declarative knowledge when interpreting age-associated changes in discriminative conditioned learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anger management: Age differences in emotional modulation of visual processing.

Although positive and negative images enhance the visual processing of young adults, recent work suggests that a life-span shift in emotion processing goals may lead older adults to avoid negative images. To examine this tendency for older adults to regulate their intake of negative emotional information, the current study investigated age-related differences in the perceptual boost received by probes appearing over facial expressions of emotion. Visually-evoked event-related potentials were recorded from the scalp over cortical regions associated with visual processing as a probe appeared over facial expressions depicting anger, sadness, happiness, or no emotion. The activity of the visual system in response to each probe was operationalized in terms of the P1 component of the event-related potentials evoked by the probe. For young adults, the visual system was more active (i.e., greater P1 amplitude) when the probes appeared over any of the emotional facial expressions. However, for older adults, the visual system displayed reduced activity when the probe appeared over angry facial expressions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Happy mouth and sad eyes: Scanning emotional facial expressions.

There is evidence that specific regions of the face such as the eyes are particularly relevant for the decoding of emotional expressions, but it has not been examined whether scan paths of observers vary for facial expressions with different emotional content. In this study, eye-tracking was used to monitor scanning behavior of healthy participants while looking at different facial expressions. Locations of fixations and their durations were recorded, and a dominance ratio (i.e., eyes and mouth relative to the rest of the face) was calculated. Across all emotional expressions, initial fixations were most frequently directed to either the eyes or the mouth. Especially in sad facial expressions, participants more frequently issued the initial fixation to the eyes compared with all other expressions. In happy facial expressions, participants fixated the mouth region for a longer time across all trials. For fearful and neutral facial expressions, the dominance ratio indicated that both the eyes and mouth are equally important. However, in sad and angry facial expressions, the eyes received more attention than the mouth. These results confirm the relevance of the eyes and mouth in emotional decoding, but they also demonstrate that not all facial expressions with different emotional content are decoded equally. Our data suggest that people look at regions that are most characteristic for each emotion. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Age differences in recognition of emotion in lexical stimuli and facial expressions.

Age differences in emotion recognition from lexical stimuli and facial expressions were examined in a cross-sectional sample of adults aged 18 to 85 (N = 357). Emotion-specific response biases differed by age: Older adults were disproportionately more likely to incorrectly label lexical stimuli as happiness, sadness, and surprise and to incorrectly label facial stimuli as disgust and fear. After these biases were controlled, findings suggested that older adults were less accurate at identifying emotions than were young adults, but the pattern differed across emotions and task types. The lexical task showed stronger age differences than the facial task, and for lexical stimuli, age groups differed in accuracy for all emotional states except fear. For facial stimuli, in contrast, age groups differed only in accuracy for anger, disgust, fear, and happiness. Implications for age-related changes in different types of emotional processing are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rapid detection of snakes by Japanese monkeys (Macaca fuscata): An evolutionarily predisposed visual system.

Humans appear extremely sensitive to biologically threatening stimuli, such as snakes. In visual search tasks, humans respond to pictures of snakes faster than pictures of flowers. The authors report that macaque monkeys (Macaca fuscata), reared in a laboratory and with no experience with snakes, respond, as do humans, to pictures of snakes among flowers faster than vice versa (Experiment 1). This was also the case when grayscale pictures were used (Experiment 2). These results provide the first evidence of enhanced visual detection of evolutionarily relevant threat stimuli in nonhuman primates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contingency awareness and fear inhibition in a human fear-potentiated startle paradigm.

Fear-potentiated startle is defined as an increase in the magnitude of the startle reflex in the presence of a stimulus that was previously paired with an aversive event. It has been proposed that a subject's awareness of the contingencies in the experiment may affect fear-potentiated startle. The authors adapted a conditional discrimination procedure (AX+/BX-), previously validated in animals, to a human fear-potentiated startle paradigm in 50 healthy volunteers. This paradigm allows for an assessment of fear-potentiated startle during threat conditions as well as inhibition of fear-potentiated startle during safety conditions. A response keypad was used to assess contingency awareness on a trial-by-trial basis. Both aware and unaware subjects showed fear-potentiated startle. However, awareness was related to stimulus discrimination and fear inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fear, Conditioning, and Aging: Theoretical Comment on LaBar et al. (2004).

Age-related impairments in associative learning have been found in studies using classical conditioning of motor responses. However, it is as yet unclear whether conditioning of fear responses is similarly affected by aging. K. S. La Bar et al. (2004; see record 2004-19432-004) aimed to address this issue by studying age effects on fear conditioning applying a discrimination paradigm. Considering these results, this commentary discusses methodological issues in investigating fear conditioning as well as similarities and differences between associative learning of motor and autonomic responses with respect to neuronal substrates, susceptibility to aging, and the role of awareness of stimulus contingencies in mediating aging effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Judgments of facial expressions of emotion in profile.

Despite the fact that facial expressions of emotion have signal value, there is surprisingly little research examining how that signal can be detected under various conditions, because most judgment studies utilize full-face, frontal views. We remedy this by obtaining judgments of frontal and profile views of the same expressions displayed by the same expressors. We predicted that recognition accuracy when viewing faces in profile would be lower than when judging the same faces from the front. Contrarily, there were no differences in recognition accuracy as a function of view, suggesting that emotions are judged equally well regardless of from what angle they are viewed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The time course of consolidation in visual working memory.

How long does it take to form a durable representation in visual working memory? Several theorists have proposed that this consolidation process is very slow. Here, we measured the time course of consolidation. Observers performed a change-detection task for colored squares, and shortly after the presentation of the first array, pattern masks were presented at the locations of each of the colored squares to disrupt representations that had not yet been consolidated. Performance on the memory task was impaired when the delay between the colored squares and the masks was short, and this effect became larger when the number of colored squares was increased. The rate of consolidation was approximately 50 ms per item, which is considerably faster than previous proposals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)