Visual scanpaths and facial affect recognition in delusion-prone individuals: Increased sensitivity to threat?

Attentional bias in German Armed Forces veterans with and without posttraumatic stress symptoms - An eye-tracking investigation and group comparison

BACKGROUND AND OBJECTIVES

Most eye tracking based paradigms evidence patterns of sustained attention on threat coupled with low evidence for vigilance to or avoidance of threat in posttraumatic stress symptoms (PTSS). Still, eye tracking data on attention bias is particularly limited for military population. This eye tracking study investigated attentional bias in PTSS in a sample of German Armed Forces veterans.

METHODS

Veterans with deployment-related PTSS (N = 24), veterans with deployment-related traumatization without PTSS (N = 28), and never-deployed healthy veterans (N = 18) were presented with pairs of combat and neutral pictures, pairs of general threat and neutral pictures, and pairs of emotional and neutral faces. Their eye gazes were tracked during a free viewing task. 3 x 3 x 2 mixed general linear model analyses were conducted. Internal consistency of attention bias indicators was calculated for the entire sample and within groups.

RESULTS

Veterans with PTSS dwelled longer on general threat AOIs in contrast to non-exposed controls and shorter on general threat and combat associated neutral AOIs in contrast to both control groups. Veterans with PTSS entered faster to general threat AOIs than non-exposed controls. Veterans with PTSS showed circumscribed higher attention fluctuation in contrast to controls. Internal consistency varied across attention bias indicators.

LIMITATIONS

Statistical power was reduced due to recruitment difficulties.

CONCLUSIONS

Evidence is provided for the maintenance hypothesis in PTSS. No robust evidence is provided for hypervigilant behavior in PTSS. Findings on attention bias variability remain unclear, calling for more investigations in this field.

Understanding Clinical Reasoning through Visual Scanpath and Brain Activity Analysis

This paper presents an experimental study that analyzes learners’ visual behaviour and brain activity in clinical reasoning. An acquisition protocol was defined to record eye tracking and EEG data from 15 participants as they interact with a computer-based learning environment called Amnesia, a medical simulation system that assesses the analytical skills of novice medicine students while they solve patient cases. We use gaze data to assess learners’ visual focus and present our methodology to track learners’ reasoning process through scanpath pattern analysis. We also describe our methodology for examining learners’ cognitive states using mental engagement and workload neural indexes. Finally, we discuss the relationship between gaze path information and EEG and how our analyses can lead to new forms of clinical diagnostic reasoning assessment.

The attenuated visual scanpaths of patients with schizophrenia whilst recognizing emotional facial expressions are worsened in natural social scenes

Alteration of visual scanpaths under emotional facial expression in schizophrenia patients has been described in recent years; however, it is not clear whether such results are different when they transfer to faces in natural social scenes. The present study was designed to investigate the effects of emotional faces in natural social scenes on the gaze patterns of patients with schizophrenia, compared to gaze at isolated faces. A novel theme identification task was used where participants selected a positive, neutral or negative word to describe an emotional picture. Participants were 29 patients with schizophrenia and 31 healthy controls. The Positive and Negative Syndrome Scale (PANSS) and the Scale of Social Function in Psychosis Inpatients (SSPI) were used to assess symptoms and social functioning. In total, patients with schizophrenia showed significantly fewer fixations, saccades numbers and decreased fixations in areas of interest. As expected, patients showed shorter scanpath length, but only in the pictures with social settings. Furthermore, the effect size of scanpaths parameters under social scene was all greater than isolated face. In addition, patients compared to controls showed more abnormal scanpath parameters processing negative and neutral faces than positive faces, especially in social scene. The present study suggests that scanpath length for social scene faces may be more sensitive than for isolated face pictures. Our findings further support restricted scanpath whilst recognizing emotional facial expressions in natural social scenes as a favorable topic for further investigation as a trait marker.

Subclinical paranoid beliefs and enhanced neural response during processing of unattractive faces

The perception of faces and consequent social inferences are fundamental for interpersonal communication. While facial expression is important for interindividual communication, constitutional and acquired features are crucial for basic emotions of attraction or repulsion. An emotional bias in face processing has been shown in schizophrenia, but the neurobiological mechanisms are unclear. Studies on the interaction between face processing and the emotional state of healthy individuals may help to elucidate the pathogenesis of the paranoid syndrome in psychosis. This study addressed facial attractiveness and paranoid ideas in a non-clinical population. Using functional magnetic resonance imaging (fMRI), we investigated neural activation patterns of 99 healthy subjects during the passive perception of a dynamic presentation of faces with different attractiveness. We found that the perceived attractiveness of faces was linked to the activity of face processing and limbic regions including the fusiform gyrus, amygdala, and prefrontal areas. Paranoid beliefs interacted with perceived attractiveness in these regions resulting in a higher response range and increased activation after the presentation of unattractive faces. However, no behavioral interactions between reported subjective attractiveness and paranoid beliefs were found. The results showed that increased activation of limbic brain regions is linked to paranoid beliefs. Since similar correlations were found in clinical populations with paranoid syndromes, we suggest a dimension of emotional dysregulation ranging from subclinical paranoid beliefs to paranoid schizophrenia.

Psychobiology of threat appraisal in the context of psychotic experiences: A selective review

A key factor in the transition to psychosis is the appraisal of anomalous experiences as threatening. Cognitive models of psychosis have identified attentional and interpretative biases underlying threat-based appraisals. While much research has been conducted into these biases within the clinical and cognitive literature, little examination has occurred at the neural level. However, neurobiological research in social cognition employing threatening stimuli mirror cognitive accounts of maladaptive appraisal in psychosis. This review attempted to integrate neuroimaging data regarding social cognition in psychosis with the concepts of attentional and interpretative threat biases. Systematic review methodology was used to identify relevant articles from Medline, PsycINFO and EMBASE, and PubMed databases. The selective review showed that attentional and interpretative threat biases relate to abnormal activation of a range of subcortical and prefrontal structures, including the amygdala, insula, hippocampus, anterior cingulate, and prefrontal cortex, as well as disrupted connectivity between these regions, when processing threatening and neutral or ambiguous stimuli. Notably, neural findings regarding the misattribution of threat to neutral or ambiguous stimuli presented a more consistent picture. Overall, however, the findings for any specific emotion were mixed, both in terms of the specific brain areas involved and the direction of effects (increased/decreased activity), possibly owing to confounds including small sample sizes, varying experimental paradigms, medication, and heterogeneous, in some cases poorly characterised, patient groups. Further neuroimaging research examining these biases by employing experimentally induced anomalous perceptual experiences and well-characterised large samples is needed for greater aetiological specificity.

The categories, frequencies, and stability of idiosyncratic eye-movement patterns to faces

The spatial pattern of eye-movements to faces considered typical for neurologically healthy individuals is a roughly T-shaped distribution over the internal facial features with peak fixation density tending toward the left eye (observer's perspective). However, recent studies indicate that striking deviations from this classic pattern are common within the population and are highly stable over time. The classic pattern actually reflects the average of these various idiosyncratic eye-movement patterns across individuals. The natural categories and respective frequencies of different types of idiosyncratic eye-movement patterns have not been specifically investigated before, so here we analyzed the spatial patterns of eye-movements for 48 participants to estimate the frequency of different kinds of individual eye-movement patterns to faces in the normal healthy population. Four natural clusters were discovered such that approximately 25% of our participants' fixation density peaks clustered over the left eye region (observer's perspective), 23% over the right eye-region, 31% over the nasion/bridge region of the nose, and 20% over the region spanning the nose, philthrum, and upper lips. We did not find any relationship between particular idiosyncratic eye-movement patterns and recognition performance. Individuals' eye-movement patterns early in a trial were more stereotyped than later ones and idiosyncratic fixation patterns evolved with time into a trial. Finally, while face inversion strongly modulated eye-movement patterns, individual patterns did not become less distinct for inverted compared to upright faces. Group-averaged fixation patterns do not represent individual patterns well, so exploration of such individual patterns is of value for future studies of visual cognition.

Response of schizophrenic patients to dynamic facial expressions: an event-related potentials study

OBJECTIVE

Patients with schizophrenia have an impaired ability to respond to faces and may specifically show an impaired response to dynamic facial expressions. Here we investigated the responses of schizophrenic patients and healthy controls to dynamic facial images using event-related potentials (ERPs).

METHODS

We showed 13 schizophrenic patients and 13 healthy controls visual stimuli comprising facial expressions that continually changed from neutral to emotional.

RESULTS

N200 latencies and P100-N200 peak-to-peak amplitudes in controls were prolonged or greater for dynamic emotions in comparison with those for static stimuli, but the group with schizophrenia showed no significant differences in responses to dynamic and static emotions. A significant negative correlation was observed between N200 latencies for dynamic negative emotion and PANSS (positive and negative syndrome scale) general psychopathology scale scores.

CONCLUSIONS

A combination of hypersensitivity to static emotions and hyposensitivity to dynamic emotions in people with schizophrenia might underlie the absence of differences in response to these stimuli. A tendency in the schizophrenic group to hypersensitivity to static emotions might arise from the enhanced fear and arousal characteristics of this group; their hyposensitivity to dynamic emotions might result from controlled attentional bias away from facial expressions to reduce fear and anxiety.

Visual scanning of emotional faces in schizophrenia

This study investigated eye movement differences during facial emotion recognition between 101 patients with chronic schizophrenia and 101 controls. Independent of facial emotion, patients with schizophrenia processed facial information inefficiently; they showed significantly more direct fixations that lasted longer to interest areas (IAs), such as the eyes, nose, mouth, and nasion. The total fixation number, mean fixation duration, and total fixation duration were significantly increased in schizophrenia. Additionally, the number of fixations per second to IAs (IA fixation number/s) was significantly lower in schizophrenia. However, no differences were found between the two groups in the proportion of number of fixations to IAs or total fixation number (IA fixation number %). Interestingly, the negative symptoms of patients with schizophrenia negatively correlated with IA fixation number %. Both groups showed significantly greater attention to positive faces. Compared to controls, patients with schizophrenia exhibited significantly more fixations directed to IAs, a higher total fixation number, and lower IA fixation number/s for negative faces. These results indicate that facial processing efficiency is significantly decreased in schizophrenia, but no difference was observed in processing strategy. Patients with schizophrenia may have special deficits in processing negative faces, and negative symptoms may affect visual scanning parameters.

Emotion recognition in psychosis: no evidence for an association with real world social functioning

BACKGROUND

Patients with psychotic disorders show impairments in the recognition of emotions in other people. These impairments have been associated with poor social functioning as measured by self-report questionnaires, clinical interviews and laboratory-based tests of social skills. The ecological validity of these tests, however, is low. Associations were examined between emotion recognition and daily life social interactions in 50 patients diagnosed with a non-affective psychotic disorder and 67 healthy controls.

METHODS

All participants were assessed with the Degraded Facial Affect Recognition Task (DFAR), a computer test measuring the recognition of emotional facial expressions. Social functioning in daily life was assessed using the Experience Sampling Method (a random time sampling technique) with focus on measures of social context and appraisal of the social situation.

RESULTS

Groups differed significantly in the recognition of angry faces, whereas no differences existed for other emotions. There were no associations between emotion recognition and social functioning in daily life and there was no evidence for differential associations in patients as compared to controls.

DISCUSSION

Social functioning, when assessed in an ecologically valid fashion, is not sensitive to variation in the traditional experimental assessment of emotion recognition. Real life measures of functioning should guide research linking the handicaps associated with psychosis to underlying cognitive and emotional dysregulation.

Current visual scanpath research: a review of investigations into the psychotic, anxiety, and mood disorders

The human visual system is comprised of an array of complex organs, which jointly decode information from visible light to construct a meaningful representation of the surrounding environment. The study of visual scanpaths transpired in a bid to enhance our understanding of the role of eye movements underpinning adaptive functioning as well as psychopathology and was further aided by the advent of modern eye-tracking techniques. This review provides a background to the nature of visual scanpaths, followed by an overview and critique of eye movement studies in specific clinical populations involving the psychotic, anxiety, and mood disorders, and concludes with suggested directions for future research. We performed a Medline and PsycInfo literature search, based on variations of the terms "visual scanpath," "eye-tracking," and "eye movements," in relation to articles published from 1986 to the present. Eye-tracking studies in schizophrenia mostly concurred with the existence of a "restricted" scanning strategy, characterized by fewer number of fixations of increased durations, with shorter scanpath lengths, and a marked avoidance of salient features, especially in relation to facial emotion perception. This has been interpreted as likely reflecting dual impairments in configural processing as well as gestalt perception. Findings from the anxiety and mood disorders have conversely failed to yield coherent results, with further research warranted to provide corroborating evidence and overcome identified methodological limitations. Future studies should also look toward applying similar techniques to related disorders as well as conducting parallel neuroimaging investigations to elucidate potential neurobiological correlates.

Do patients with schizophrenia have a general or specific deficit in the perception of social threat? A meta-analytic study

This study investigates whether social cognitive deficits found in patients with schizophrenia are specific to social threat stimuli, and whether the deficits increase across the delusion spectrum from a subclinical sample to clinical manifestation. The authors presented the meta-analytic review of the published literature on social threat perception performance in three kinds of group comparisons: a subclinical group and a healthy control group, a schizophrenia group and a healthy control group, and a schizophrenia with delusion symptoms group and a healthy control group. The meta-analysis of 20 studies yielded six weighted effect sizes. The largest differences were found between the schizophrenia with delusion group and the healthy controls in both the threat and non-threat conditions. No differences were found between the effect sizes in the threat-related condition and the non-threat condition in any of the three group comparisons. Age was found to be significantly correlated with the effect sizes. The performance differences in both the threat and non-threat conditions reflect a generalized performance deficit, rather than a specific deficit, in the perception of social threat stimuli among patients with schizophrenia.

An unusual attraction to the eyes in Williams-Beuren syndrome: a manipulation of facial affect while measuring face scanpaths

INTRODUCTION

This study aimed to investigate face scanpaths and emotion recognition in Williams-Beuren syndrome (WBS) and whether: (1) the eyes capture the attention of WBS individuals faster than typically developing mental age-matched controls; (2) WBS patients spend abnormally prolonged periods of time viewing the eye region; and (3) emotion recognition skills or eye gaze patterns change depending on the emotional valance of the face.

METHODS

Visual scanpaths were recorded while 16 WBS patients and 16 controls passively viewed happy, angry, fearful, and neutral faces. Emotion recognition was subsequently measured.

RESULTS

The eyes did not capture the attention of WBS patients faster than controls, but once WBS patients attended to the eyes, they spent significantly more time looking at this region. Unexpectedly, WBS patients showed an impaired ability to recognise angry faces, but face scanpaths were similar across the different facial expressions.

CONCLUSIONS

Findings suggest that face processing is atypical in WBS and that emotion recognition and eye gaze abnormalities in WBS are likely to be more complex than previously thought. Findings highlight the need to develop remediation programmes to teach WBS patients how to explore all facial features, enhancing their emotion recognition skills and "normalising" their social interactions.

Jumping to conclusions and perceptions in early psychosis: relationship with delusional beliefs

INTRODUCTION

Previous research has suggested that biases in cognitive processes involved in everyday reasoning may contribute to the development of delusional beliefs. The aim of this study was to explore jumping to conclusions (JTC), a data-gathering bias, and jumping to perceptions (JTP), a bias towards believing ambiguous perceptual events are real and external.

METHODS

Individuals with current delusions (n=17), remitted delusions (n=17), both recruited from an early psychosis service, and nonclinical participants (n=35) were compared on a probabilistic reasoning task, an auditory perceptual bias task, and the Barely Visible Words task.

RESULTS

The deluded participants did not demonstrate the expected JTC bias; therefore the relationship between JTC and JTP could not be examined. However, both clinical groups exhibited a JTP bias on the auditory perceptual bias task. In contrast, the lowered perceptual threshold for threat displayed by the control group was absent in the clinical groups.

CONCLUSIONS

These results suggest that the JTP bias may be a trait characteristic in those with a propensity to delusions, and that these individuals may also show a bias away from threat.

A preliminary investigation on the relationship between color-word Stroop task performance and delusion-proneness in nonpsychiatric adults

The current study examined whether there is a relationship between the dimension of delusion-proneness and performance on the color-word Stroop task. As dysfunction in the anterior cingulate cortex (ACC) has been related to both Stroop task performance and the presence of delusions in various psychiatric populations, we hypothesized that impaired Stroop performance would relate to increased delusion-proneness in a nonpsychiatric sample. A total of 36 college students, representing a wide range of scores on a measure of delusion-proneness (Peters et al. Delusions Inventory-PDI-21), completed a computerized version of the classic color-word Stroop task. Results revealed a statistically significant positive correlation between the PDI-21 score and the Stroop effect. The pattern of results suggests that reduced efficiency of Stroop performance is related to increasing levels of delusion-proneness. This study appears to be the first to report this relationship across a continuum of delusion-proneness in a nonpsychiatric sample. This finding contributes to the cognitive neurobiological understanding of delusions and adds further support for the dimensional construct of propensity for delusions.

Emotion categorization perception in schizophrenia in conversations with different social contexts

OBJECTIVE

The aim of the present study was to investigate whether the boundaries between the happy and angry emotions of schizophrenia would be influenced by social context and the difference in emotion categorization boundaries between schizophrenia patients and healthy controls.

METHOD

Eighteen patients with schizophrenia and 16 healthy controls were given a forced-choice emotion identification task in which they were required to listen to a series of conversations with different social contexts. The stimuli were linear morphed facial expressions between 'happy' and 'angry' emotions. For each type of social context, the shift point was used as the parameter to estimate when the subjects began to perceive the morphed facial expression as angry. The response slope was used to estimate how abruptly this change in perception occurred.

RESULTS

There was no significant difference in the schizophrenia group in the shift point of emotion categorization perception for four categories of conversations occurring in different social contexts. Compared with the healthy controls, the schizophrenia group demonstrated a steeper response slope at the shift point regardless of the conversation type.

CONCLUSION

The patients with schizophrenia were less discriminative in their categorization of emotion perception in conversations with different social contexts. The schizophrenia patients, however, were more alert to angry facial expressions in the process of facial expressions morphing from happy to angry, independent of the social context.

Allocation of attention to the eye and mouth region of faces in schizophrenia patients

INTRODUCTION

The present study examined whether reduced attentiveness to facial features and biased weighting of attention to the eye and mouth region might explain deficits in face processing in schizophrenia.

METHODS

Healthy controls (n=21) and schizophrenia patients (n=28) from an African Xhosa population were asked to detect target stimuli (dots) superimposed on pictures of faces. General attentiveness to facial features was assessed by measuring overall reaction times to targets superimposed on feature areas of faces and attentiveness to the eye versus mouth region by comparing reaction times to targets on the upper and lower parts of faces.

RESULTS

Patients exhibited generally slower target detection speed than comparison subjects but the strength of the attentional bias towards the eyes did not differ between groups (i.e., the reaction time gain for targets in the eye region). A regression analysis indicated, however, that generally slower target detection speed and an attentional bias away from the mouth predicted a deficit in the recognition of open-mouth angry facial expressions in schizophrenia patients.

CONCLUSIONS

The results give partial support for hypothesis that reduced overall attentiveness to faces and a failure to utilise visual information in salient facial features may underlie affect processing deficits in schizophrenia.

Neuropsychological aspects of delusional disorder

Delusional disorders (DDs) are clinically rare syndromes characterized by false beliefs that are held with firm conviction despite counterevidence. The neuropsychology of DDs is poorly understood. Two partially opposing models--a cognitive bias model and a cognitive deficit model--have received mixed empiric support, partly because most research has been carried out in patients with paranoid schizophrenia, with which the nosologic association of DDs is unknown. Based on these models, we review empiric findings concerning the neuropsychology of DDs (narrowly defined). We conclude that DDs can best be seen as extreme variations of cognitive mechanisms involved in rapid threat detection and defensive harm avoidance. From this viewpoint, the two models seem to be complementary in explanatory power rather than contradictory. Future research may help to clarify the question of gene-environment interaction involvement in the formation of delusional beliefs.

Correlates of delusion-like experiences in a non-psychotic community sample

OBJECTIVE

Several large population-based studies have reported that otherwise-well individuals endorse items related to delusion-like experiences. The aim of the present study was to examine selected correlates of delusion-like experiences in a sample of non-psychotic individuals.

METHOD

Subjects (n=310) were screened with the Diagnostic Interview for Psychosis in order to exclude psychotic disorders. Delusion-like experiences were assessed with the Peters Delusional Inventory (PDI). Non-parametric statistics were used to assess the relationship between total PDI score and a range of demographic (age, sex, migrant status, paternal age), physical (minor physical anomalies) symptom-related variables (hallucinations, awareness of thought disorder) and family history of mental illness.

RESULTS

The median (range) PDI score was 4 (0-26), while one-third of the subjects endorsed seven or more items. The presence of a family history of any psychiatric condition was significantly correlated with a higher PDI score. PDI score was significantly positively correlated with endorsement of hallucinations and awareness of thought disorder. PDI was not significantly associated with sex, family history of schizophrenia, paternal age, migrant status nor scores related to minor physical anomalies. There was a trend level association between younger age and higher PDI score.

CONCLUSION

Delusion-like experiences are relatively common in non-psychotic individuals. The association with a family history of mental disorders provides clues to the mechanisms underlying the profile of delusion-like experience.

Kognitive Verhaltenstherapie von Wahn und Halluzinationen

Zusammenfassung. Theoretischer Hintergrund: In den letzten 10-15 Jahren sind eine Reihe von kognitiv-behavioralen Interventionen entwickelt und evaluiert worden, die auf eine direkte Reduktion von Wahn und Halluzinationen abzielen. Gleichzeitig mehren sich Arbeiten aus der Grundlagenforschung zu Schizophrenie, die darauf hindeuten, dass Wahn und Halluzinationen mit spezifischen kognitiven Verarbeitungsstilen assoziiert sind. Als solche gelten unter anderem voreiliges Schlussfolgern, Schwierigkeiten in der Perspektivenübernahme (Theory-of-Mind), external-personale Attributionsstile und fehlerhafte Quellenattribution. Ziele: 1) die wichtigsten experimentellen Untersuchungen und Ergebnisse zu kognitiven Prozessen bei Wahn und Halluzinationen verständlich darzustellen, 2) eine Einführung in die therapeutischen Interventionen zur Veränderung der Symptome zu bieten und 3) zu bewerten, inwieweit die experimentellen Befunde in die Entwicklung von Therapiestrategien zu Wahn und Halluzinationen eingeflossen sind, bzw. durch spezifische Befunde gedeckt werden. Schlussfolgerungen: Die Mehrzahl der Interventionen setzt indirekt an den gefundenen kognitiven Auffälligkeiten an, wobei offen bleibt, in wie weit ihre Wirkung auf eine Veränderung der kognitiven Verarbeitungsstile zurückgeht. Obwohl die kognitive Umstrukturierung dysfunktionaler Selbstkonzepte einen wesentlichen Bestandteil der kognitiven Interventionen darstellt, ist die empirische Evidenz für die Rolle negativer Selbstkonzepte bei der Entstehung von Wahn und Halluzinationen bislang uneindeutig.

Fronto-limbic and autonomic disjunctions to negative emotion distinguish schizophrenia subtypes

Schizophrenia patients show a disconnection in amygdala-medial prefrontal cortex and autonomic arousal systems for processing fear. Concurrent functional magnetic resonance imaging [fMRI] and skin conductance recording were used to determine whether these disturbances are specific to fear, or present in response to other signals of danger. We also examined whether these disturbances distinguish a specific symptom profile. During scanning, 27 schizophrenia (13 paranoid, 14 nonparanoid) and 22 matched healthy control subjects viewed standardized facial expressions of fear, anger and disgust (versus neutral). Skin conductance responses [SCRs]were acquired simultaneously to assess phasic increases in arousal. 'With-arousal' versus 'without-arousal' responses were analysed using non-parametric methods. For controls, 'with-arousal' responses were associated with emotion-specific activity for fear (amygdala), disgust (insula) and anger (anterior cingulate), together with common medial prefrontal cortex [MPFC] engagement, as predicted. Schizophrenia patients displayed abnormally increased phasic arousal, with concomitant reductions in emotion-specific regions and MPFC. These findings may reflect a general disconnection between central and autonomic systems for processing signals of danger. This disjunction was most apparent in patients with a profile of paranoia, coupled with poor social function and insight. Heightened autonomic sensitivity to signals of fear, threat or contamination, without effective neural mechanisms for appraisal, may underlie paranoid delusions which concern threat and contamination, and associated social and interpersonal difficulties.

Emotional context processing is impaired in schizophrenia

INTRODUCTION

Following considerable evidence for impaired context processing and facial emotion recognition in schizophrenia, this study examined the ability of schizophrenia patients to utilise contextual information when judging the meaning of facial expressions.

METHODS

22 healthy and 20 schizophrenia participants completed the "vignette-face" task (Carroll & Russell, 1996) in which target facial expressions are preceded by vignettes describing situational information that is discrepant in affective valence; judgements reflect either the dominance of the emotional context or the facial expression. Measures of basic facial emotion recognition and executive function were also obtained.

RESULTS

On the vignette-face task, schizophrenia patients did not utilise contextual information for specific story-face pairs, whereas controls more commonly judged the emotion in line with contextual information. Most consistently, the responses of schizophrenia patients reflected neither situational nor facial cues when contextual cues suggested a complex mental state paired with a negative or threat-related expression (e.g., anger, fear, sadness). Facial affect processing ability was a significant predictor of the successful social context integration in the vignette-face task.

CONCLUSION

The reduced influence of context upon threat-related expressions in schizophrenia may contribute to the misperception of threat in situations where contextual information should appease such an interpretation.

The effects of angry and happy expressions on recognition memory for unfamiliar faces in delusion-prone individuals

Numerous studies suggest a cognitive bias for threat-related material in delusional ideation. However, few studies have examined this bias using a memory task. We investigated the influence of delusion-proneness on identity and expression memory for angry and happy faces. Participants high and low in delusion-proneness were presented with happy and angry faces and were later asked to recognise the same faces displaying a neutral expression. They also had to remember what the initial expressions of the faces had been. Remember/know/guess judgments were asked for both identity and expression memory. Results showed that delusion-prone participants better recognised the identity of angry faces compared to non-delusional participants. Also, this difference between the two groups was mainly due to a greater number of remember responses in delusion-prone participants. These findings extend previous studies by showing that delusions are associated with a memory bias for threat-related stimuli.

Selective attention to threatening faces in delusion-prone individuals

INTRODUCTION

Selective attention to threat-related information has been associated with clinical delusions in schizophrenia and nonclinical delusional ideation in healthy individuals. However, it is unclear whether biased attention for threat reflects early engagement effects on selective attention, or later difficulties in disengaging attention from perceived threat. The present study examined which of these processes operate in nonclinical delusion-prone individuals.

METHODS

A total of 100 psychologically healthy participants completed the Peters et al. (1999) Delusions Inventory (PDI). Twenty-two scoring in the upper quartile (high-PDI group) and 22 scoring in the lower quartile (low-PDI group) completed a modified dot-probe task. Participants detected dot-probes appearing 200, 500, or 1250 ms after an angry-neutral face pair or a happy-neutral face pair.

RESULTS

High-PDI individuals responded faster to dot-probes presented in the same location as angry compared to happy faces at the short 200 ms stimulus onset asynchrony (SOA), but only when the emotional faces were presented to the left visual field. At the two longer SOAs (500 ms, 1250 ms), the high-PDI group were also faster to respond to dot-probes presented in the same location as angry compared to happy faces and slower to respond to dot-probes presented in different spatial locations to angry (vs. happy) faces. The latter effects were seen whether emotional faces were presented to the left or the right visual field.

CONCLUSIONS

Results support the operation of emotion-selective engagement and defective disengagement for threat-related facial expressions (i.e., anger) in delusion-prone individuals.

Data gathering: biased in psychosis?

This study examined whether the probabilistic reasoning bias referred to as a "jumping-to-conclusions" (JTC) style of reasoning, which, according to previous research, is associated with particular psychotic symptoms such as delusions, represents a trait that can also be detected in nonpsychotic relatives of patients with schizophrenia and in nonpsychotic individuals with a high level of psychotic experiences. Participants were, in order of level of psychosis liability, 40 patients with schizophrenia or a schizoaffective disorder, 40 first-degree nonpsychotic relatives, 41 participants from the general population with above average expression of psychotic experiences, and 53 participants from the general population with an average level of psychotic experiences. A "jumping-to-conclusions" bias was assessed using the beads task. A dose-response relationship was found in the association between level of psychosis liability and JTC (defined as needing only a single bead to complete the beads task) (odds ratio [OR] linear trend = 1.59, 95% CI: 1.13-2.24), and, independently, alinear association was apparent between JTC and level of delusional ideation (OR linear trend = 2.59, 95% CI: 1.18-5.69). In addition, the association between psychosis liability and JTC was generally much stronger as the level of delusional ideation was higher. JTC is associated with liability to psychosis (trait), in particular if the psychosis phenotype is characterized by delusional ideation (state).

ADHD and schizophrenia phenomenology: visual scanpaths to emotional faces as a potential psychophysiological marker?

Commonalities in the clinical phenomenology and psychopharmacology of ADHD and schizophrenia are reviewed. The potential of psychostimulants to produce psychotic symptoms emphasizes the need for objective psychophysiological distinctions between these disorders. Impaired emotion perception in both disorders is discussed. It is proposed that visual scanpaths to facial expressions of emotion might prove a potentially useful psychophysiological distinction between ADHD and schizophrenia. There is consistent evidence that both facial affect recognition and scanpaths to facial expressions are impaired in schizophrenia, with emerging empirical evidence showing that facial affect recognition is impaired in ADHD also. Brain imaging studies show reduced activity in the medial prefrontal and limbic (amygdala) brain regions required to process emotional faces in schizophrenia, but suggest more localized loss of activity in these regions in ADHD. As amygdala activity in particular has been linked to effective visual scanning of face stimuli, it is postulated that condition-specific breakdowns in these brain regions that subserve emotional behavior might manifest as distinct scanpath aberrations to facial expressions of emotion in schizophrenia and ADHD.

Social threat perception and the evolution of paranoia

Rapid and efficient judgments about the significance of social threat are important for species survival and may recruit specialized neurocognitive systems, consistent with biological models of threat processing. We review cognitive, psychophysiological, neuropsychological, and neuroimaging evidence in support of specialized neural networks subserving the processing of facial displays of threat. Cognitive research suggests that faces depicting anger are detected quickly when presented amongst other facial expressions, on the basis of distinguishing facial features. Psychophysiological investigations using visual scanpath techniques provide evidence for increased foveal attention to facial features of threat-related expressions (anger, fear), which may facilitate rapid detection and subsequent appraisal of the significance of threat (such as the direction of impending threat). Neuropsychological and neuroimaging studies implicate a primary role for the amygdale and pre-frontal cortices in interpreting signs of danger from facial expressions and other social stimuli. Subtle disturbances in these neurocognitive systems underlying efficient threat detection (manifesting in attentional biases and aberrant neural activity) may result in abnormally heightened perception of social threat, as seen in clinical levels of social anxiety and/or persecutory delusions in schizophrenia. Clinical states of paranoia may therefore reflect normal variation (i.e. biases) in the adaptive mechanisms which have evolved, in the Darwinian sense, to facilitate efficient threat detection in humans. As such, clinical levels of paranoia may represent the inevitable cost of efficient threat perception--or 'justified' suspicion--that is necessary for survival of the human species.

Visual scanpaths to threat-related faces in deluded schizophrenia

This study examined visuo-cognitive processing of threat-related (anger, fear) and non-threat faces (happy, sad, neutral) in deluded schizophrenia (n=11), non-deluded schizophrenia (n=8), and healthy control (n=22) participants. Focal analyses examined scanpath aberrations for particular facial expressions in sub-groups of schizophrenia patients determined by the presence or absence of overt delusions. Deluded schizophrenia subjects exhibited significantly fewer fixations of shorter duration for all faces, and fewer fixations of reduced duration to the feature areas of negative facial expressions (anger, sad), compared with healthy controls. Compared with non-deluded schizophrenia subjects, deluded subjects exhibited fewer fixations to fear expressions and more fixations to the feature areas of happy expressions. These findings were revealed in the context of restricted scanning (reduced number and duration of fixations, shorter scanpath length and shorter duration of fixations to facial features) in the entire schizophrenia group (n=19) compared with healthy controls. The findings suggest a controlled attentional bias away from the feature areas of negative facial expressions in deluded schizophrenia, that is, specific to threat-related expressions compared with non-deluded schizophrenia subjects. This controlled bias away from negative social stimuli in deluded schizophrenia is discussed in terms of an attentional style of 'vigilance-avoidance' operating across early and late stages of information processing.