Anxiety-related bias in the classification of emotionally ambiguous facial expressions

Impaired identification of fearful faces in Generalised Social Phobia

BACKGROUND

Cognitive models and interventions for anxiety assume that socially anxious individuals interpret ambiguous social information in a threatening manner. However, experimental evidence for this hypothesised cognitive bias is mixed. The present study is novel in using a signal detection approach to clarify whether Generalised Social Phobia (GSP) is associated with biased identification of emotionally ambiguous facial expressions.

METHODS

16 patients with GSP and 17 non-anxious volunteers classified ambiguous emotional facial expressions, with each face reflecting a blend of two emotions: angry-happy, fearful-happy and fearful-angry. Discrimination accuracy and response criterion were assessed.

RESULTS

Patients with GSP showed significantly poorer discrimination of ambiguous emotional facial expressions that contained an element of fear (i.e., fearful-happy and fearful-angry expressions), compared to non-anxious controls. The groups did not significantly differ in discrimination of faces which lacked fear content (i.e., angry-happy blend), or on measures of response criterion.

LIMITATIONS

Small sample size, coexisting depressive symptoms.

CONCLUSIONS

Findings indicate a selective impairment in fear identification in GSP. Results are discussed with reference to neurocognitive models of anxiety, and research on serotonergic modulation of emotional face processing.

Putting pain assessment into practice: why is it so painful?

OBJECTIVE

To explore some of the reasons for poor compliance with the use of standardized pain assessment tools in clinical practice, despite numerous guidelines and standards mandating their use.

METHODS

First, a review of research and clinical audit literature on the effects of standardized pain assessment tools on patient or process outcomes was conducted, and findings were critiqued. Second, a synthesis of recent literature on the biopsychosocial mechanisms of human detection and recognition of pain in others was presented. Third, the implications for pain assessment in pediatric clinical settings were discussed.

RESULTS

There is a lack of good-quality evidence for the efficacy, effectiveness or cost-benefit of standardized pain assessment tools in relation to pediatric patient or process outcomes. Research suggests that there may be greater variability than previously appreciated in the ability and motivation of humans when assessing pain in others. It remains unknown whether pain detection skills or motivation to relieve pain in others can be improved or overcome by standardized methods of pain assessment.

DISCUSSION

Further research is needed to understand the intra- and interpersonal dynamics in clinical assessment of pain in children and to test alternative means of achieving diagnosis and treatment of pain. Until this evidence is available, guidelines recommending standardized pain assessment must be clearly labelled as being based on principles or evidence from other fields of practice, and avoid implying that they are 'evidence based'.

Interpretation of emotionally ambiguous faces in older adults

Research suggests that there is an age-related decline in the processing of negative emotional information, which may contribute to the reported decline in emotional problems in older people. We used a signal detection approach to investigate the effect of normal aging on the interpretation of ambiguous emotional facial expressions. High-functioning older and younger adults indicated which emotion they perceived when presented with morphed faces containing a 60% to 40% blend of two emotions (mixtures of happy, sad, or angry faces). They also completed measures of mood, perceptual ability, and cognitive functioning. Older and younger adults did not differ significantly in their ability to discriminate between positive and negative emotions. Response-bias measures indicated that older adults were significantly less likely than younger adults to report the presence of anger in angry-happy face blends. Results are discussed in relation to other research into age-related effects on emotion processing.

The role of trait anxiety in the recognition of emotional facial expressions

Previous work has suggested that elevated levels of trait anxiety are associated with an increased ability to accurately recognize the facial expression of fear. However, to date, recognition has only been assessed after viewing periods of 10s, despite the fact that the process of emotion recognition from faces typically takes a fraction of this time. The current study required participants with either high or low levels of non-clinical trait anxiety to make speeded emotional classification judgments to a series of facial expressions drawn from seven emotional categories. Following previous work it was predicted that recognition of fearful facial expressions would be more accurate in the high-trait anxious group compared with the low-trait anxious group. However, contrary to this prediction, no anxiety-related differences in emotion perception were observed across all seven emotions. This suggests that anxiety does not influence the perception of fear as has been previously proposed.

Acute tryptophan depletion in healthy volunteers enhances punishment prediction but does not affect reward prediction

Central serotonin (5-HT) has been implicated in emotional and behavioral control processes for many decades, but its precise contribution is not well understood. We used the acute tryptophan depletion procedure in young healthy volunteers to test the hypothesis that central 5-HT is critical for predicting punishment. An observational reversal-learning task was employed that provided separate measures of punishment and reward prediction. Under baseline, subjects made more prediction errors for punishment-associated stimuli than for reward-associated stimuli. This bias was abolished after central 5-HT depletion, which enhanced the ability to predict punishment while not affecting reward prediction. The selective potentiation of punishment prediction concurs with recent theorizing, suggesting that central 5-HT carries a prediction error for future punishment, but not for future reward (Daw et al, 2002). Furthermore, the finding highlights the importance of central 5-HT in resilience to adversity and may have implications for a variety of neuropsychiatric disorders including depression and anxiety.

Empathy, social functioning and schizotypy

Whilst affective empathy is concerned with one's emotional response to the affective state of another, cognitive empathy refers to one's understanding of another's mental state, and deficits in both are believed to contribute to the social behavioral abnormalities associated with schizophrenia. The present study aimed to test whether individual differences in normally distributed schizotypal personality traits are related to cognitive and affective empathy, and whether any observed association between schizotypy and empathy mediates the relationship between schizotypy and (reduced) social functioning. Non-clinical volunteers (N=223) completed measures of schizotypal personality, cognitive and affective empathy, social functioning and negative affect. The results indicated that higher schizotypy was associated with reduced empathy, poorer social functioning and increased negative affect. Of the specific schizotypal dimensions (positive, negative and disorganized), only negative schizotypy was significantly associated with social functioning, and this relationship persisted even after controlling for negative affect. Further, affective empathy functioned as a partial mediator in this relationship. These data show that the relationship between negative schizotypy and social functioning is at least partially attributable to deficits in affective empathy.

Social anxiety and interpretation biases for facial displays of emotion: emotion detection and ratings of social cost

The current study assessed the processing of facial displays of emotion (Happy, Disgust, and Neutral) of varying emotional intensities in participants with high vs. low social anxiety. Use of facial expressions of varying intensities allowed for strong external validity and a fine-grained analysis of interpretation biases. Sensitivity to perceiving negative evaluation in faces (i.e., emotion detection) was assessed at both long (unlimited) and brief (60 ms) stimulus durations. In addition, ratings of perceived social cost were made indicating what participants judged it would be like to have a social interaction with a person exhibiting the stimulus emotion. Results suggest that high social anxiety participants did not demonstrate biases in their sensitivity to perceiving negative evaluation (i.e. disgust) in facial expressions. However, high social anxiety participants did estimate the perceived cost of interacting with someone showing disgust to be significantly greater than low social anxiety participants, regardless of the intensity of the disgust expression. These results are consistent with a specific type of interpretation bias in which participants with social anxiety have elevated ratings of the social cost of interacting with individuals displaying negative evaluation.

Neurocognitive mechanisms of anxiety: an integrative account

Anxiety can be hugely disruptive to everyday life. Anxious individuals show increased attentional capture by potential signs of danger, and interpret expressions, comments and events in a negative manner. These cognitive biases have been widely explored in human anxiety research. By contrast, animal models have focused upon the mechanisms underlying acquisition and extinction of conditioned fear, guiding exposure-based therapies for anxiety disorders. Recent neuroimaging studies of conditioned fear, attention to threat and interpretation of emotionally ambiguous stimuli indicate common amygdala-prefrontal circuitry underlying these processes, and suggest that the balance of activity within this circuitry is altered in anxiety, creating a bias towards threat-related responses. This provides a focus for future translational research, and targeted pharmacological and cognitive interventions.

A comparison of selective attention and facial processing biases in typically developing children who are high and low in self-reported trait anxiety

The relationship between children's anxiety and cognitive biases was examined in two tasks. A group of 50 children aged 10 to 11 years (mean = 11 years, SD = 3.71 months) was given two tasks. The first tested children's selective attention (SA) to threat in an emotional Stroop task. The second explored facial processing biases using morphed angry-neutral and happy-neutral emotional expressions that varied in intensity. Faces with varying levels of emotion (25% emotion-75% neutral, 50% emotion-50% neutral, 100% emotion-0% neutral [prototype] and 150% emotion-0% neutral [caricature]) were judged as being angry or happy. Results support previous work highlighting a link between anxiety and SA to threat. In addition, increased anxiety in late childhood is associated with decreased ability to discriminate facial expression. Finally, lack of discrimination in the emotional expression task was related to lack of inhibition to threat in the Stroop task.

Jumping to interpretations: Social anxiety disorder and the identification of emotional facial expressions

A small body of research suggests that socially anxious individuals show biases in interpreting the facial expressions of others. The current study included a clinically anxious sample in a speeded emotional card-sorting task in two conditions (baseline and threat) to investigate several hypothesized biases in interpretation. Following the threat manipulation, participants with generalized social anxiety disorders (GSADs) sorted angry cards with greater accuracy, but also evidenced a greater rate of neutral cards misclassified as angry, as compared to nonanxious controls. The controls showed the opposite pattern, sorting neutral cards with greater accuracy but also misclassifying a greater proportion of angry cards as neutral, as compared to GSADs. These effects were accounted for primarily by low-intensity angry cards. Results are consistent with previous studies showing a negative interpretive bias, and can be applied to the improvement of clinical interventions.

Amygdala reactivity to emotional faces at high and low intensity in generalized social phobia: a 4-Tesla functional MRI study

Using functional magnetic resonance imaging, we measured amygdala reactivity to faces varying on emotional intensity in subjects with generalized social phobia (GSP) and matched healthy controls, and observed greater bilateral activation to high (vs. low) intensity expressions in the phobic group, suggesting that more arousing social-emotional cues contribute to limbic hyperactivity in GSP.

Facial emotion recognition in trait anxiety

The study investigated the relationship between recognition of emotional facial expressions and trait anxiety. A nonclinical sample of 19 participants with high-trait anxiety was selected, using the trait version of the State-Trait Anxiety Inventory, and compared with a sample of 20 participants with low-trait anxiety on a facial expression recognition task. Visual stimuli were 42 faces, representing seven emotional expressions: anger, sadness, happiness, fear, surprise, disgust and neutral. Participants had to identify the emotion portrayed by each face. Results showed that participants with high-trait anxiety recognized fear faces significantly better while the two groups did not differ in recognition of other facial expressions.

The development of information processing biases in childhood anxiety: a review and exploration of its origins in parenting

The aim of this paper is to explore parenting as one potential route through which information processing biases for threat develop in children. It reviews information processing biases in childhood anxiety in the context of theoretical models and empirical research in the adult anxiety literature. Specifically, it considers how adult models have been used and adapted to develop a theoretical framework with which to investigate information processing biases in children. The paper then considers research which specifically aims to understand the relationship between parenting and the development of information processing biases in children. It concludes that a clearer theoretical framework is required to understand the significance of information biases in childhood anxiety, as well as their origins in parenting.

Anxiety and sensitivity to eye gaze in emotional faces

This paper reports three studies in which stronger orienting to perceived eye gaze direction was revealed when observers viewed faces showing fearful or angry, compared with happy or neutral, emotional expressions. Gaze-related spatial cueing effects to laterally presented fearful faces and centrally presented angry faces were also modulated by the anxiety level of participants, with high- but not low-state anxious individuals revealing enhanced shifts of attention. In contrast, both high- and low-state anxious individuals demonstrated enhanced orienting to averted gaze when viewing laterally presented angry faces. These results provide novel evidence for the rapid integration of facial expression and gaze direction information, and for the regulation of gaze-cued attention by both the emotion conveyed in the perceived face and the degree of anxiety experienced by the observer.

Categorical perception of vocal emotion expressions

Continua of vocal emotion expressions, ranging from one expression to another, were created using speech synthesis. Each emotion continuum consisted of expressions differing by equal physical amounts. In 2 experiments, subjects identified the emotion of each expression and discriminated between pairs of expressions. Identification results show that the continua were perceived as 2 distinct sections separated by a sudden category boundary. Also, discrimination accuracy was generally higher for pairs of stimuli falling across category boundaries than for pairs belonging to the same category. These results suggest that vocal expressions are perceived categorically. Results are interpreted from an evolutionary perspective on the function of vocal expression.

Individual differences in threat sensitivity predict serotonergic modulation of amygdala response to fearful faces

RATIONALE

In this study we used functional magnetic resonance imaging (fMRI) to examine the effects of acute tryptophan depletion (ATD), a well-recognised method for inducing transient cerebral serotonin depletion, on brain activation to fearful faces.

OBJECTIVES

We predicted that ATD would increase the responsiveness of the amygdala to fearful faces as a function of individual variation in threat sensitivity.

METHODS

Twelve healthy male volunteers received a tryptophan depleting drink or a tryptophan balancing amino acid drink (placebo) in a double-blind crossover design. Five hours after drink ingestion participants were scanned whilst viewing fearful, happy and neutral faces.

RESULTS

Consistent with previous findings, fearful faces induced significant signal change in the bilateral amygdala/hippocampus as well as the fusiform face area and the right dorsolateral prefrontal cortex. Furthermore, ATD modulated amygdala/hippocampus activation in response to fearful relative to happy faces as a function of self-reported threat sensitivity (as measured with the Behavioral Inhibition Scale; Carver CS, White TL (1994) Behavioral inhibition, behavioral activation, and affective responses to impending reward and punishment: the BIS/BAS scales. J Pers Soc Psychol 67:319-333).

CONCLUSION

The data support the hypothesis that individual variation in threat sensitivity interacts with manipulation of 5-HT function to bias the processing of amygdala-dependent threat-relevant stimuli.

Emotion recognition deficits in pediatric anxiety disorders: implications for amygdala research

INTRODUCTION

Anxiety disorders in adults involve aberrant processing of emotional information that is hypothesized to reflect perturbations in the amygdala. This study examines the relationship between face-emotion recognition and anxiety in a sample of children and adolescents participating in a brain-imaging study of amygdala structure and function.

METHODS

This study recruited 15 children and adolescents with ongoing anxiety disorders and 11 psychiatrically healthy comparisons group-matched on age, gender, and IQ. Face-emotion recognition was assessed using the Diagnostic Analysis of Nonverbal Accuracy Scale (DANVA).

RESULTS

Children and adolescents with anxiety disorders exhibited significantly poorer performance on the face-emotion recognition task compared to healthy controls (z = 2.2; p < 0.05). This difference was found only for expressions posed by adults but not children.

DISCUSSION

Reduced accuracy on a face-emotion recognition test is consistent with perturbed amygdala function in pediatric anxiety disorders.

CONCLUSION

As this study was conducted in a sample undergoing a neuroimaging investigation of amygdala integrity, future analyses will examine associations among amygdala function, clinical anxiety, and face-recognition abilities.

Sex differences in the perception of affective facial expressions: do men really lack emotional sensitivity?

There is evidence that men and women display differences in both cognitive and affective functions. Recent studies have examined the processing of emotions in males and females. However, the findings are inconclusive, possibly the result of methodological differences. The aim of this study was to investigate the perception of emotional facial expressions in men and women. Video clips of neutral faces, gradually morphing into full-blown expressions were used. By doing this, we were able to examine both the accuracy and the sensitivity in labelling emotional facial expressions. Furthermore, all participants completed an anxiety and a depression rating scale. Research participants were 40 female students and 28 male students. Results revealed that men were less accurate, as well as less sensitive in labelling facial expressions. Thus, men show an overall worse performance compared to women on a task measuring the processing of emotional faces. This result is discussed in relation to recent findings.

Anterior cingulate activation in high trait anxious subjects is related to altered error processing during decision making

BACKGROUND

Individuals with high trait anxiety (HTA) can be studied to examine the effect of elevated levels of anxiety on the processing of stimuli and the selection of actions. The anterior cingulate cortex has been implicated in the detection and processing of errors. This investigation examined the hypothesis that HTA subjects are more sensitive to errors than nonanxious comparison subjects during a simple decision-making task and show increased activation in the anterior cingulate, particularly at low error rates.

METHODS

Thirteen HTA subjects were compared with 13 normal trait anxiety (NTA: 40th-60th percentile) subjects during functional magnetic resonance imaging while performing a two-choice prediction task at three different error rates.

RESULTS

Both HTA and NTA subjects performed similarly during a simple two-choice prediction task; however, during the low-error-rate condition, activation in the anterior cingulate and medial prefrontal cortex was significantly higher in HTA subjects and was correlated with trait but not state anxiety.

CONCLUSIONS

These results support the idea that HTA subjects devote more processing resources to decision making than do NTA subjects during times in which there is little chance of incorrect responding (i.e., the low-error-rate condition). The extent to which this altered activation within the anterior cingulate contributes to anxiety-proneness remains to be determined.