The effects of familiarity and emotional expression on face processing examined by ERPs in patients with schizophrenia

How psychological and descriptive narratives modulate the perception of facial emotional expressions: an event-related potentials (ERPs) study

The aim of the present study was to investigate whether stories with high and low narrative transport exert different effects on neural activation in response to facial emotional expressions. Thirty-one participants were randomly assigned to two groups based on the type of story they read: psychological narrative with high narrative transport (6 women and 10 men; age M = 34.38 ± 8.77); descriptive narrative with low narrative transport (9 women and 6 men; age M = 24.07 ± 7.38). The electroencephalographic activity of the participants in response to emotional facial expressions (joy, anger, fear, sadness) was recorded before (T0) and after (T1) the reading task. The findings indicated that the reading task modulated the early brain response (P1, N170) to emotional facial expressions, irrespective of the narrative type. However, only in the psychological narrative group was the amplitude of the P100 found to be positively associated with the extent to which an individual was transported into the narrative. In summary, the findings appear to indicate that an increased degree of transport into the narrative is associated with a greater internal simulation process of emotions and mental states. This, in turn, modulates the perception of the real social world after reading.

Demystifying authenticity: Behavioral and neurophysiological signatures of self-positivity for authentic and presented selves

Authenticity has captivated scholars. But what is it? An emerging view considers it exaggerated favorability (self-enhancement), whereas traditional views regard it as self-accuracy and self-consistency. We tested these theoretical views by contrasting the authentic self with the presented self, a highly desirable representation. Behaviorally, participants ascribed less positivity to the authentic self: They endorsed more negative traits and were faster to admit having them; also, they endorsed fewer positive traits and were slower to admit having them. Neurally, participants manifested preferential processing of threatening information (P1), followed by preferential processing of favorable information (N170), about the presented self (than authentic self), indicating its brittleness. At a later stage (LPP), participants engaged in more elaborate processing of threatening and favorable information about the authentic self, indicating its subjective importance. Authenticity, albeit mostly positive, allows room for negativity.

Subjectively salient faces differ from emotional faces: ERP evidence

The self-face is processed differently than emotional faces. A question arises whether other highly familiar and subjectively significant non-self faces (e.g. partner's face) are also differentiated from emotional faces. The aim of this event-related potential (ERP) study was to investigate the neural correlates of personally-relevant faces (the self and a close-other's) as well as emotionally positive (happy) and neutral faces. Participants were tasked with the simple detection of faces. Amplitudes of N170 were more negative in the right than in the left hemisphere and were not modulated by type of face. A similar pattern of N2 and P3 results for the self-face and close-other's face was observed: they were associated with decreased N2 and increased P3 relative to happy and neutral faces. However, the self-face was preferentially processed also when compared to a close-other's face as revealed by lower N2 and higher P3 amplitudes. Nonparametric cluster-based permutation tests showed an analogous pattern of results: significant clusters for the self-face compared with all other faces (close-other's, happy, neutral) and for close-other's face compared to happy and neutral faces. In summary, the self-face prioritization was observed, as indicated by significant differences between one's own face and all other faces. Crucially, both types of personally-relevant faces differed from happy faces. These findings point to the pivotal role of subjective evaluation of the saliency factor.

Posterior theta activity reveals an early signal of self-face recognition

Self-related visual information, especially one's own face and name, are processed in a specific, prioritized way. However, the spatio-temporal brain dynamics of self-prioritization have remained elusive. Moreover, it has been unclear whether this prioritization is an effect of enhancement and amplification, or rather a facilitating automatization of processing self-referential information. In this EEG study, 25 married women (who changed their surnames after marriage, so that their past and present surnames could be used as stimuli) performed a detection task with faces and names from five categories: self, self from the past, friend, famous, and unknown person. The aim was to determine the temporal and spatial characteristics of early electrophysiological markers of self-referential processing. We report results of event-related component (ERP) and time-frequency analyses. In the ERPs, the earliest self-relevance effect was displayed only 300 ms after stimulus onset in the midfrontal N2, and later in the parietal P3b, independently of the stimulus type. No self-relevance effect was found on the N170 component. However, local theta power at the occipito-temporal (visual) areas and inter-regional theta phase coherence between the visual and midfrontal areas showed that self-relevance differentiation of faces began already about 100-300 ms after stimulus onset. No such early effects were found for names. The results are discussed in terms of the time-course, functional localization, stimulus-specificity, and automatization of self-prioritization.

Effects of aging on face processing: An ERP study of the own-age bias with neutral and emotional faces

Older adults systematically show an enhanced N170 amplitude during the visualization of facial expressions of emotion. The present study aimed to replicate this finding, further investigating if this effect is specific to facial stimuli, present in other neural correlates of face processing, and modulated by own-age faces. To this purpose, younger (n = 25; M_age = 28.36), middle-aged (n = 23; M_age = 48.74), and older adults (n = 25; M_age = 67.36) performed two face/emotion identification tasks during an EEG recording. The results showed that groups did not differ regarding P100 amplitude, but older adults had increased N170 amplitude for both facial and non-facial stimuli. The event-related potentials analysed were not modulated by an own-age bias, but older faces elicited larger N170 in the Emotion Identification Task for all groups. This increased amplitude may reflect a higher ambiguity of older faces due to age-related changes in their physical features, which may elicit higher neural resources to decode. Regarding P250, older faces elicited decreased amplitudes than younger faces, which may reflect a reduced processing of the emotional content of older faces. This interpretation is consistent with the lower accuracy obtained for this category of stimuli across groups. These results have important social implications and suggest that aging may hamper the neural processing of facial expressions of emotion, especially for own-age peers.

The time course of categorical perception of facial expressions

Decoding emotions on others' faces is one of the most important functions of the human brain, which has been widely studied in cognitive neuroscience. However, the precise time course of facial expression categorization in the human brain is still a matter of debate. Here we used an original paradigm to measure categorical perception of facial expression changes during event-related potentials (ERPs) recording, in which a face stimulus dynamically switched either to a different expression (between-category condition) or to the same expression (within-category condition), the physical distance between the two successive faces being equal across conditions. The switch between faces generated a negative differential potential peaking at around 160 ms over occipito-temporal regions, similar in term of latency and topography to the well-known face-selective N170 component. This response was larger in the condition where the switch occurred between faces that were perceived as having different facial expressions compared to the same expression. In addition, happy expressions were categorized around 20 ms faster than fearful expressions (respectively, 135 and 156 ms). These findings provide evidence that changes of facial expressions are categorically perceived as early as 160 ms following stimulus onset over the occipito-temporal cortex.

Electrophysiological Studies of Reception of Facial Communication in Autism Spectrum Disorder and Schizophrenia

Autism spectrum disorder (ASD) and schizophrenia spectrum disorders (SZ) are characterized by difficulty with social cognition and atypical reception of facial communication - a key area in the Research Domain Criteria framework. To identify areas of overlap and dissociation between ASD and SZ, we review studies of event-related potentials (ERP) to faces across ASD and SZ populations, focusing on ERPs implicated in social perception: P100, N170, N250, and P300. There were many inconsistent findings across studies; however, replication was strongest for delayed N170 latency in ASD and attenuated N170 amplitude in SZ. These results highlight the challenges of replicating research findings in heterogeneous clinical populations and the need for transdiagnostic research that continuously quantifies behavior and neural activity across neurodevelopmental disorders.

Facial emotion perception abilities are related to grey matter volume in the culmen of cerebellum anterior lobe in drug-naïve patients with first-episode schizophrenia

Impaired capability for understanding and interpreting the expressions on other people's faces manifests itself as a core feature of schizophrenia, contributing to social dysfunction. With the purpose of better understanding of the neurobiological basis of facial emotion perception deficits in schizophrenia, we investigated facial emotion perception abilities and regional structural brain abnormalities in drug-naïve patients with first-episode schizophrenia, and then examined the correlation between them. Fifty-two drug-naive patients with first-episode schizophrenia and 29 group-matched healthy controls were examined for facial emotion perception abilities assessed with the Facial Emotion Categorization and performed magnetic resonance imaging. The Facial Emotion Categorization data were inserted into a logistic function model so as to calculate shift point and slope as outcome measurements. Voxel-based morphometry was applied to investigate regional grey matter volume (GMV) alterations. The relationship between facial emotion perception and GMV was explored in patients using voxel-wise correlation analysis within brain regions that showed a significant GMV alterations in patients compared with controls. The schizophrenic patients performed differently on Facial Emotion Categorization tasks from the controls and presented a higher shift point and a steeper slope. Relative to the controls, patients showed GMV reductions in the superior temporal gyrus, middle occipital gyrus, parahippocampa gyrus, posterior cingulate, the culmen of cerebellum anterior lobe, cerebellar tonsil, and the declive of cerebellum posterior lobe. Importantly, abnormal performance on Facial Emotion Categorization was found correlated with GMV alterations in the culmen of cerebellum anterior lobe in schizophrenia. This study suggests that reduced GMV in the culmen of cerebellum anterior lobe occurs in first-episode schizophrenia, constituting a potential neuropathological basis for the impaired facial emotion perception in schizophrenia.

Cortical activity involved in perception and imagery of visual stimuli in a subject with aphantasia. An EEG case report

Aphantasia has been described as the inability to voluntarily evoke mental images using the "mind's eye." We studied a congenital aphantasic subject using neuropsychological testsand 64 channel EEG recordings, in order to studycortical activity involved in perception and imagery evaluating event-related potentials(N170, P200, N250). The subject is in the normal range of the neuropsychological tests performed, except for specific imagery tests. The EEG results show that when he evokes the same mental image, he starts the evoking process from left temporal instead of frontal areas, he does not activate occipital visual nor left anterior parietal areas.

An Event-Related Potential Investigation of Early Visual Processing Deficits During Face Perception in Youth at Clinical High Risk for Psychosis

Impairments in early visual face perception are well documented in patients with schizophrenia. Specifically, event-related potential (ERP) research in patients with schizophrenia has demonstrated deficits in early sensory processing of stimulus properties (P1 component) and the structural encoding of faces (N170 component). However, it is not well understood if similar impairments are present in individuals at clinical high risk (CHR) for psychosis (ie, those in the putative prodromal stage of the illness). Thus, it is unknown if face perception deficits are the result of illness onset or are present in the high-risk period for the illness. The present study used the ERP technique to examine neural activation when viewing facial emotion expressions and objects in 44 CHR and 47 control adolescents and young adults (N = 91). P1 amplitude was similar across groups, indicating that early sensory processing impairments did not substantially contribute to face perception deficits in CHR youth. CHR youth exhibited reduced N170 amplitude compared to controls when viewing faces but not objects, implicating a specific deficit in the structural encoding of faces rather than a general perceptual deficit. Further, whereas controls demonstrated the expected face-selective N170 effect (ie, larger amplitude for faces than objects), CHR youth did not, which suggests that facial emotion expressions do not elicit the expected preferential perceptual processing for critical social information in individuals at CHR for psychosis. Together, these findings provide valuable information regarding the specific impairments contributing to face perception deficits in the high-risk period where treatment stands to aid in preventing illness progression.

The rapid and automatic categorization of facial expression changes in highly variable natural images

Emotional expressions are quickly and automatically read from human faces under natural viewing conditions. Yet, categorization of facial expressions is typically measured in experimental contexts with homogenous sets of face stimuli. Here we evaluated how the 6 basic facial emotions (Fear, Disgust, Happiness, Anger, Surprise or Sadness) can be rapidly and automatically categorized with faces varying in head orientation, lighting condition, identity, gender, age, ethnic origin and background context. High-density electroencephalography was recorded in 17 participants viewing 50 s sequences with natural variable images of neutral-expression faces alternating at a 6 Hz rate. Every five stimuli (1.2 Hz), variable natural images of one of the six basic expressions were presented. Despite the wide physical variability across images, a significant F/5 = 1.2 Hz response and its harmonics (e.g., 2F/5 = 2.4 Hz, etc.) was observed for all expression changes at the group-level and in every individual participant. Facial categorization responses were found mainly over occipito-temporal sites, with distinct hemispheric lateralization and cortical topographies according to the different expressions. Specifically, a stronger response was found to Sadness categorization, especially over the left hemisphere, as compared to Fear and Happiness, together with a right hemispheric dominance for categorization of Fearful faces. Importantly, these differences were specific to upright faces, ruling out the contribution of low-level visual cues. Overall, these observations point to robust rapid and automatic facial expression categorization processes in the human brain.

The upside-down self: One's own face recognition is affected by inversion

One's own face is recognized more efficiently than any other face, although the neural mechanisms underlying this phenomenon remain poorly understood. Considering the extensive visual experience that we have with our own face, some authors have proposed that self-face recognition involves a more analytical perceptual strategy (i.e., based on face features) than other familiar faces, which are commonly processed holistically (i.e., as a whole). However, this hypothesis has not yet been tested with brain activity data. In the present study, we employed an inversion paradigm combined with event-related potential (ERP) recordings to investigate whether the self-face is processed more analytically. Sixteen healthy participants were asked to identify their own face and a familiar face regardless of its orientation, which could either be upright or inverted. ERP analysis revealed an enhanced amplitude and a delayed latency for the N170 component when faces were presented in an inverted orientation. Critically, both the self and a familiar face were equally vulnerable to the inversion effect, suggesting that the self-face is not processed more analytically than a familiar face. In addition, we replicated the recent finding that the attention-related P200 component is a specific neural index of self-face recognition. Overall, our results suggest that the advantage for self-face processing might be better explained by the engagement of self-related attentional mechanisms than by the use of a more analytical visuoperceptual strategy.

The N170 is Sensitive to Long-term (Personal) Familiarity of a Face Identity

The N170 is a large deflection of the human electroencephalogram (EEG), peaking at about 170 milliseconds over the occipito-temporal cortex after the sudden onset of a face stimulus. The N170 reflects perceptual awareness of a face and its onset corresponds to the emergence of reliable face-selectivity in the human brain. However, whether sensitivity to the long-term familiarity of a face identity emerges already at this early time-point remains debated. Here we provide a brief survey of the 45 published studies comparing the N170 response to unfamiliar and familiar (famous, experimentally familiarized, personally familiar and own) faces. Even though effects of familiarity on the N170 are relatively small and inconsistent across studies, this overview indicates that face familiarity significantly increases the N170 amplitude. This effect is especially present for personally familiar faces, learned in natural conditions. In the human brain, effects linked to familiarity with specific facial identities therefore appear to emerge between 150 and 200 ms in occipito-temporal brain regions, i.e., shortly after the onset of face-selectivity but at the same time as the earliest high-level effects of immediate unfamiliar face identity repetition. This observation challenges standard neurocognitive models with a clear-cut distinction between perceptual and memory stages in human face recognition.

Configural processing of emotional bodies and faces in patients with attention deficit hyperactivity disorder

Introduction: Attention Deficit Disorder (ADHD) is associated with interpersonal problems and difficulties in inferring other peoples' emotions. Previous research has focused on face processing, mostly in children. Our study investigated configural processing of emotional bodies and faces in adults with ADHD in comparison with healthy controls, analyzing P100, N170 and P250 event-related potentials (ERPs) and relating them to (socio)cognitive functioning. Method: Nineteen patients with ADHD and 25 healthy controls were presented upright and inverted bodies and faces which had to be categorized as neutral, happy or angry while ERPs were recorded. Additionally, sociocognitive and executive functioning was assessed. Results: In ADHD patients relative to controls, recognition of emotions depicted by bodies but not by faces was impaired and P100 amplitudes were enhanced for angry bodies. Furthermore, patients showed enhanced P250 amplitudes in response to both bodies and faces, specifically for happy and neutral emotions. Larger N170 amplitudes to bodies and faces correlated with lower alexithymia scores only in controls, while enhanced P250 amplitudes to both categories were associated with poorer inhibition only in patients. Conclusion: Adults with ADHD show potentially compensatory enhanced semantic processing of emotional bodies and faces, as reflected by increased P250 amplitudes, associated with poorer executive functioning and subtle alterations of emotional and configural processing, as reflected by ERPs.

Neurophysiological substrates of configural face perception in schizotypy

Face perception is a highly developed function of the human visual system. Previous studies of event-related potentials (ERPs) have identified a face-selective ERP component (negative peak at about 170 ms after stimulus onset, N170) in healthy participants. In contrast, patients with schizophrenia exhibit reduced amplitude of the N170, which may represent a pathological deficit in the neurophysiology of face perception. Interestingly, healthy humans with schizophrenia-like experiences (schizotypy) also exhibit abnormal processing of face perception. Yet, it has remained unknown how schizotypy in healthy humans is associated with the neurophysiological substrates of face perception. Here, we recruited 35 healthy participants and assessed their schizotypy by the magical ideation rating scale. We used high-density electroencephalography to obtain ERPs elicited by a set of Mooney faces (face and non-face visual stimuli). We investigated median and mean reaction times and visual ERP components in response to the stimuli. We observed a significant difference in N170 amplitude between the two face-stimulus conditions and found that the measured schizotypy scores were significantly correlated with both reaction times and N170 amplitude in response to the face stimuli across all participants. Our results thus support the model of schizotypy as a manifestation of a continuum between healthy individuals and patients with schizophrenia, where the N170 impairment serves as a biomarker for the degree of pathology along this continuum.

Sex differences in event-related potential (ERP) waveforms of primary psychotic disorders: A systematic review

Research aimed at understanding primary psychotic disorders such as schizophrenia, schizophreniform disorder, and schizoaffective disorder, with electrophysiological methods has flourished over recent years. However, a significant component that is often overlooked or underreported in electrophysiological research of psychosis is the factor of biological sex. Thus, the goal of this systematic review was to summarize the current understanding of EEG sex differences in primary psychotic disorders. Our study found a consistent sex difference relating to the P300 component (male amplitude < females), and that research examining sex differences of ERP waveforms, other than the P300, is very limited with ambiguous findings. This review also addressed the lack of consideration of sex as an influencing factor in electrophysiological research.

Childhood maltreatment impacts the early stage of facial emotion processing in young adults with negative schizotypy

Childhood maltreatment (CM) is a factor of risk for psychosis and is associated with alterations in facial emotion processing.Negative symptoms of schizophrenia-spectrum disorders are associated with deficits in facial emotion processing, but research findings on schizotypy are mixed. This study examined the early stage of facial emotion processing in young adults with high levels of negative schizotypy (NS) and explored the impact of childhood maltreatment. On the basis of the Social and Physical Anhedonia subscales of the Chapman Psychosis-Proneness Scales, a total of 74 high-NS and 52 low-NS individuals were recruited to complete the Childhood Trauma Questionnaire and the dot-probe task. The P100 and N170 components of event-related potentials were measured to assess the processing of four facial expressions of emotion. The high-NS group showed significantly reduced P100 amplitudes for all facial expressions. Angry and fearful expressions elicited larger N170 amplitudes than disgusted and happy expressions. Happy expressions elicited shorter N170 latencies than disgusted expressions. Compared to the high-NS group without CM, the high-NS group with CM had a longer latency of P100. Individuals with high NS, compared to individuals with low NS, have impaired fundamental visual processing, but intact processing of facial figurations. Childhood maltreatment may be a factor responsible for the pathological state of the visual pathway in high NS group.

Malleability of the self: electrophysiological correlates of the enfacement illusion

Self-face representation is fundamentally important for self-identity and self-consciousness. Given its role in preserving identity over time, self-face processing is considered as a robust and stable process. Yet, recent studies indicate that simple psychophysics manipulations may change how we process our own face. Specifically, experiencing tactile facial stimulation while seeing similar synchronous stimuli delivered to the face of another individual seen as in a mirror, induces 'enfacement' illusion, i.e. the subjective experience of ownership of the other's face and a bias in attributing to the self, facial features of the other person. Here we recorded visual Event-Related Potentials elicited by the presentation of self, other and morphed faces during a self-other discrimination task performed immediately after participants received synchronous and control asynchronous Interpersonal Multisensory Stimulation (IMS). We found that self-face presentation after synchronous as compared to asynchronous stimulation significantly reduced the late positive potential (LPP; 450-750 ms), a reliable electrophysiological marker of self-identification processes. Additionally, enfacement cancelled out the differences in LPP amplitudes produced by self- and other-face during the control condition. These findings represent the first direct neurophysiological evidence that enfacement may affect self-face processing and pave the way to novel paradigms for exploring defective self-representation and self-other interactions.

Social aversive conditioning in youth at clinical high risk for psychosis and with psychosis: An ERP study

BACKGROUND

Social cognition and emotion processing are compromised in schizophrenia. Disruptions in these domains may also be present during the psychosis-risk state. Aversive conditioning is an established translational research paradigm to investigate affective reactivity and learning. Using an aversive conditioning ERP paradigm with social cues, we examined whether psychosis patients and at-risk youths differentially respond to aversively conditioned faces.

METHODS

Participants (ages 10-30) were enrolled into three demographically-matched groups: clinical risk for psychosis (CR, n = 32), psychosis (PS, n = 26), and healthy control (HC, n = 33). EEGs were recorded during a delay aversive conditioning task in which three neutral faces were paired with an aversive tone at 100%, 50% and 0% contingencies. Analysis focused on group differences in ERP peaks representing visual processing (occipital P120), emotional valence (frontal VPP), and directed attention (parietal-occipital P300), for dimensions of aversiveness (100% vs. 0%) and unpredictability (50% vs. 100% + 0%).

RESULTS

HC, but not CR or PS, showed increased P300 amplitude to aversive vs. non-aversive conditioned stimuli. CR, but not PS or HC, showed increased VPP amplitude to unpredictable vs. predictable stimuli.

CONCLUSIONS

PS and CR both fail to allocate appropriate salience to social cues that are predictably aversive. CR, but not PS exhibit heightened emotional reactivity to social cues that are of uncertain salience. Clinical risk for schizophrenia may involve neural abnormalities distinct from both healthy and fully-established disease states.

Impairments of emotional face processing in schizophrenia patients: Evidence from P100, N170 and P300 ERP components in a sample of auditory hallucinators

Patients with schizophrenia show impaired face and emotional expression processing that may be due to early perceptual deficits or late impairments in higher-order emotional facial recognition. This study examined event-related potentials (ERPs) in 23 patients with schizophrenia who experience auditory hallucinations and 19 healthy controls. EEG activity was recorded from 32 scalp sites positioned according to the 10-10 placement system. Linked left and right electrodes at the mastoids served as the reference. The P100, N170 and P300 were measured during an emotional facial identification task, which included neutral, joyful, sad, angry and fearful facial expressions and non-face stimuli (chairs). P100 was measured at O_1/2 and P_7/8. N170 was measured at P_7/8. P300 was measured at P_z. Patients with schizophrenia were slower at identifying all facial expressions, including neutral ones. They also showed less positive P100 amplitude to sad, angry and fearful facial expressions. N170 amplitudes were smaller in patients in response to neutral, joyful, sad, angry, and fearful facial expression. Patients showed less positive P300 mean amplitudes to all facial expressions, including neutral ones. Within-group comparisons showed that patients exhibited a different pattern of ERP modulation across facial expressions than controls for P100 and N170, but not for P300. Our findings are compatible with the idea that behavioural and electrophysiological face-processing deficits in schizophrenia arise from early-stage deficits in visual processing.

Exploring electrophysiological correlates of social cognition in subclinical schizotypy

Impairments in social cognition and associated abnormalities in brain function are well documented in psychotic disorders. They may represent neurodevelopmental vulnerabilities and may therefore be present in less severe or even subclinical conditions of the schizophrenia spectrum, such as schizotypy. Schizotypy has features highly suggestive of social cognitive impairments, but little is known about possible related abnormalities of brain function. This exploratory pilot study examines electrophysiological event-related potentials (ERPs) implicated in schizophrenia, in 23 undergraduates with a range of subclinical schizotypal characteristics. ERPs were recorded in response to emotional face stimuli in an experimental paradigm designed to assess very early stages of social stimulus processing. Three ERPs were assessed, P100, N170 and P300. P100 and P300 were found to be related to multiple schizotypal features, but N170 was not. The results support occurrence of social cognitive impairments linked to abnormal brain function across the schizophrenia spectrum. Copyright © 2018 John Wiley & Sons, Ltd.

Beauty-related perceptual bias: Who captures the mind of the beholder?

INTRODUCTION

To explore the beauty-related perceptual bias and answers the question: Who can capture the mind of the beholder? Many studies have explored the specificity of human faces through ERP or other ways, and the materials they used are general human faces and other objects. Therefore, we want to further explore the difference between attractive faces and beautiful objects such as flowers.

METHODS

We recorded the eye movement of 22 male observers and 23 female observers using a standard two-alternative forced choice.

RESULTS

(1) The attractive faces were looked at longer and more often in comparison with the beautiful flowers; (2) fixation counts of female participants are more than male participants; and (3) the participants watched the beautiful flowers first, followed by the attractive faces, but there was no significant difference on the first fixation duration between the beautiful flowers and the attractive faces.

CONCLUSIONS

The data in this study may suggest that people prefer attractive faces to beautiful flowers.

Self- or familiar-face recognition advantage? New insight using ambient images

Self-face recognition has been widely explored in the past few years. Nevertheless, the current literature relies on the use of standardized photographs which do not represent daily-life face recognition. Therefore, we aim for the first time to evaluate self-face processing in healthy individuals using natural/ambient images which contain variations in the environment and in the face itself. In total, 40 undergraduate and graduate students performed a forced delayed-matching task, including images of one's own face, friend, famous and unknown individuals. For both reaction time and accuracy, results showed that participants were faster and more accurate when matching different images of their own face compared to both famous and unfamiliar faces. Nevertheless, no significant differences were found between self-face and friend-face and between friend-face and famous-face. They were also faster and more accurate when matching friend and famous faces compared to unfamiliar faces. Our results suggest that faster and more accurate responses to self-face might be better explained by a familiarity effect - that is, (1) the result of frequent exposition to one's own image through mirror and photos, (2) a more robust mental representation of one's own face and (3) strong face recognition units as for other familiar faces.

Fear boosts the early neural coding of faces

The rapid extraction of facial identity and emotional expressions is critical for adapted social interactions. These biologically relevant abilities have been associated with early neural responses on the face sensitive N170 component. However, whether all facial expressions uniformly modulate the N170, and whether this effect occurs only when emotion categorization is task-relevant, is still unclear. To clarify this issue, we recorded high-resolution electrophysiological signals while 22 observers perceived the six basic expressions plus neutral. We used a repetition suppression paradigm, with an adaptor followed by a target face displaying the same identity and expression (trials of interest). We also included catch trials to which participants had to react, by varying identity (identity-task), expression (expression-task) or both (dual-task) on the target face. We extracted single-trial Repetition Suppression (stRS) responses using a data-driven spatiotemporal approach with a robust hierarchical linear model to isolate adaptation effects on the trials of interest. Regardless of the task, fear was the only expression modulating the N170, eliciting the strongest stRS responses. This observation was corroborated by distinct behavioral performance during the catch trials for this facial expression. Altogether, our data reinforce the view that fear elicits distinct neural processes in the brain, enhancing attention and facilitating the early coding of faces.

Increased local connectivity of brain functional networks during facial processing in schizophrenia: evidence from EEG data

Schizophrenia is often considered to be a disconnection syndrome. The abnormal interactions between large-scale functional brain networks result in cognitive and perceptual deficits. The present study investigated event-related functional connectivity networks to compare facial processing in individuals with and without schizophrenia. Faces and tables were presented to participants, and event-related phase synchrony, represented by the phase lag index (PLI), was calculated. In addition, cortical oscillatory dynamics may be useful for understanding the neural mechanisms underlying the disparate cognitive and functional impairments in schizophrenic patients. Therefore, the dynamic graph theoretical networks related to facial processing were compared between individuals with and without schizophrenia. Our results showed that event-related phase synchrony was significantly reduced in distributed networks, and normalized clustering coefficients were significantly increased in schizophrenic patients relative to those of the controls. The present data suggest that schizophrenic patients have specific alterations, indicated by increased local connectivity in gamma oscillations during facial processing.

Mirror self-face perception in individuals with schizophrenia: Feelings of strangeness associated with one's own image

Self-face recognition is crucial for sense of identity and for maintaining a coherent sense of self. Most of our daily life experiences with the image of our own face happen when we look at ourselves in the mirror. However, to date, mirror self-perception in schizophrenia has received little attention despite evidence that face recognition deficits and self abnormalities have been described in schizophrenia. Thus, this study aims to investigate mirror self-face perception in schizophrenia patients and its correlation with clinical symptoms. Twenty-four schizophrenia patients and twenty-five healthy controls were explicitly requested to describe their image in detail during 2min whilst looking at themselves in a mirror. Then, they were asked to report whether they experienced any self-face recognition difficulties. Results showed that schizophrenia patients reported more feelings of strangeness towards their face compared to healthy controls (U=209.5, p=0.048, r=0.28), but no statistically significant differences were found regarding misidentification (p=0.111) and failures in recognition (p=0.081). Symptoms such as hallucinations, somatic concerns and depression were also associated with self-face perception abnormalities (all p-values>0.05). Feelings of strangeness toward one's own face in schizophrenia might be part of a familiar face perception deficit or a more global self-disturbance, which is characterized by a loss of self-other boundaries and has been associated with abnormal body experiences and first rank symptoms. Regarding this last hypothesis, multisensorial integration might have an impact on the way patients perceive themselves since it has an important role in mirror self-perception.

Response bias-related impairment of early subjective face discrimination in social anxiety disorders: An event-related potential study

Considerable research has shown that social anxiety disorder (SAD) is accompanied by various negative cognitive biases, such as social feedback expectancy bias, memory bias, and interpretation bias. However, whether the memory bias in individuals with SAD is actually a manifestation of response bias, and whether such response bias is associated with deficits in face discrimination, remains unclear. In the present study, we investigated response bias (i.e., a tendency to recognize more negative evaluations) to faces with positive (social acceptance) or negative (social rejection) social evaluations in individuals with SAD and healthy controls (HCs) using event-related potentials (ERPs). Behavioral results revealed significant group differences in response bias in the forced-choice recall task, but no difference in overall memory accuracy. ERP results demonstrated that HCs showed a larger N170 to faces that had rejected them as compared to those that had accepted them, but this effect was not evident in the SAD group. Further analysis showed that response bias was correlated with the ΔN170 (rejected - accepted) amplitude. We concluded that the response bias in individuals with SAD is resulted from impairments in early discrimination of social faces, as reflected by the absent early N170 differentiation effect, which was associated with their combined negative biases.

Altered attentional and perceptual processes as indexed by N170 during gaze perception in schizophrenia: Relationship with perceived threat and paranoid delusions

Using gaze information to orient attention and guide behavior is critical to social adaptation. Previous studies have suggested that abnormal gaze perception in schizophrenia (SCZ) may originate in abnormal early attentional and perceptual processes and may be related to paranoid symptoms. Using event-related brain potentials (ERPs), this study investigated altered early attentional and perceptual processes during gaze perception and their relationship to paranoid delusions in SCZ. Twenty-eight individuals with SCZ or schizoaffective disorder and 32 demographically matched healthy controls (HCs) completed a gaze-discrimination task with face stimuli varying in gaze direction (direct, averted), head orientation (forward, deviated), and emotion (neutral, fearful). ERPs were recorded during the task. Participants rated experienced threat from each face after the task. Participants with SCZ were as accurate as, though slower than, HCs on the task. Participants with SCZ displayed enlarged N170 responses over the left hemisphere to averted gaze presented in fearful relative to neutral faces, indicating a heightened encoding sensitivity to faces signaling external threat. This abnormality was correlated with increased perceived threat and paranoid delusions. Participants with SCZ also showed a reduction of N170 modulation by head orientation (normally increased amplitude to deviated faces relative to forward faces), suggesting less integration of contextual cues of head orientation in gaze perception. The psychophysiological deviations observed during gaze discrimination in SCZ underscore the role of early attentional and perceptual abnormalities in social information processing and paranoid symptoms of SCZ.

Sluggishness of Early-Stage Face Processing (N170) Is Correlated with Negative and General Psychiatric Symptoms in Schizophrenia

Patients with schizophrenia consistently exhibit abnormalities in the N170 event-related potential (ERP) component evoked by images of faces. However, the relationship between these face-specific N170 abnormalities in patients with schizophrenia and the clinical characteristics of this disorder has not been elucidated. Here, ERP recordings were conducted for patients with schizophrenia and healthy controls. The amplitude and latency of the N170 component were recorded while participants passively viewed face and non-face (table) images to explore the correlation between face-specific processing and clinical characteristics in schizophrenia. The results provided evidence for a face-specific N170 latency delay in patients with schizophrenia. The N170 latency in patients with schizophrenia was significantly longer than that in healthy controls when images of faces were presented in both upright and inverted orientations. Importantly, the face-related N170 latencies of the left temporo-occipital electrodes (P7 and PO7) were positively correlated with both negative and general psychiatric symptoms in these patients. The N170 amplitudes were weaker in patients than in controls for inverted images of both faces and non-faces (tables), with a left-hemisphere dominance. The face inversion effect (FIE), meaning the difference in N170 amplitude between upright and inverted faces, was absent in patients with schizophrenia, suggesting an abnormality of holistic face processing. Together, these results revealed a marked symptom-relevant neural delay associated with face-specific processing in patients with schizophrenia, providing additional evidence to support the demyelination hypothesis of schizophrenia.

Deficits in Early Stages of Face Processing in Schizophrenia: A Systematic Review of the P100 Component

INTRODUCTION

Schizophrenia is associated with deficits in face and affect recognition, which contribute to broader social functioning deficits. The present aim was to conduct a meta-analysis of early face processing in schizophrenia, as indexed by the P100 event-related potential component.

METHODS

Twelve studies (n = 328 patients with schizophrenia, n = 330 healthy controls) of the P100 component during face processing were evaluated by calculating Cohen's d for each study and overall weighted mean effect size (ES). In additional exploratory analyses, moderating influences of method and design were investigated, and the P100 component during face processing was evaluated based on valence: 5 studies (n = 225 patients, n = 225 controls) included neutral stimuli, 5 studies (n = 225 patients, n = 225 controls) included happy stimuli, and 4 studies (n = 209 patients, n = 209 controls) included fearful stimuli.

RESULTS

The amplitude of the P100 to face stimuli was smaller in patients relative to controls (ES = .41, P < .01). Methodological or design differences did not account for heterogeneity in ES. When split by valence, results indicate smaller P100 in patients relative to control subjects in response to neutral (ES = .32, P < .001) and happy (ES = .21, P < .05) stimuli, whereas there was no difference in response to fearful faces (ES = .09, P > .05).

DISCUSSION

The results indicate that P100 amplitude in response to faces is smaller in patients with schizophrenia, showing that socially relevant visual processing deficits begin earlier in processing than previously suggested. Additionally, the exploratory analyses suggest emotional specificity in these deficits. Ramifications for our understanding of face processing deficits and treatment development are discussed.

Non-Conscious Perception of Emotions in Psychiatric Disorders: The Unsolved Puzzle of Psychopathology

Psychophysiological and functional neuroimaging studies have frequently and consistently shown that emotional information can be processed outside of the conscious awareness. Non-conscious processing comprises automatic, uncontrolled, and fast processing that occurs without subjective awareness. However, how such non-conscious emotional processing occurs in patients with various psychiatric disorders requires further examination. In this article, we reviewed and discussed previous studies on the non-conscious emotional processing in patients diagnosed with anxiety disorder, schizophrenia, bipolar disorder, and depression, to further understand how non-conscious emotional processing varies across these psychiatric disorders. Although the symptom profile of each disorder does not often overlap with one another, these patients commonly show abnormal emotional processing based on the pathology of their mood and cognitive function. This indicates that the observed abnormalities of emotional processing in certain social interactions may derive from a biased mood or cognition process that precedes consciously controlled and voluntary processes. Since preconscious forms of emotional processing appear to have a major effect on behaviour and cognition in patients with these disorders, further investigation is required to understand these processes and their impact on patient pathology.

Categorical perception of familiarity: Evidence for a hyper-familiarity in schizophrenia

Familiarity is a crucial aspect of recognition that may be perturbed in schizophrenia patients (SZP) and may lead to delusional disorders. However, there are no existing guidelines on how to assess and treat familiarity disorders in schizophrenia. Some experimental studies have investigated familiarity processing in SZP but have produced inconsistent results, which are likely a result of methodological issues. Moreover, these studies only assessed whether familiarity processing is preserved or impaired in SZP, but not the tendency of SZP to consider unfamiliar stimuli to be familiar. By using a familiarity continuum task based on the existence of the categorical perception effect, the objective of this study was to determine whether SZP present hyper- or hypo-familiarity. To this purpose, 15 SZP and 15 healthy subjects (HS) were presented with facial stimuli, which consisted of picture morphs of unfamiliar faces and faces that were personally familiar to the participants. The percentage of the familiar face contained in the morph ranged from 5 to 95%. The participants were asked to press a button when they felt familiar with the face that was presented. The main results revealed a higher percentage of familiarity responses for SZP compared with HS from the stimuli with low levels of familiarity in the morph and a lower familiarity threshold, suggesting a hyper-familiarity disorder in SZP. Moreover, the intensity of this "hyper-familiarity" was correlated with positive symptoms. This finding clearly suggests the need for a more systematic integration of an assessment of familiarity processing in schizophrenia symptoms assessments.

Face recognition in schizophrenia disorder: A comprehensive review of behavioral, neuroimaging and neurophysiological studies

Facial emotion processing has been extensively studied in schizophrenia patients while general face processing has received less attention. The already published reviews do not address the current scientific literature in a complete manner. Therefore, here we tried to answer some questions that remain to be clarified, particularly: are the non-emotional aspects of facial processing in fact impaired in schizophrenia patients? At the behavioral level, our key conclusions are that visual perception deficit in schizophrenia patients: are not specific to faces; are most often present when the cognitive (e.g. attention) and perceptual demands of the tasks are important; and seems to worsen with the illness chronification. Although, currently evidence suggests impaired second order configural processing, more studies are necessary to determine whether or not holistic processing is impaired in schizophrenia patients. Neural and neurophysiological evidence suggests impaired earlier levels of visual processing, which might involve the deficits in interaction of the magnocellular and parvocellular pathways impacting on further processing. These deficits seem to be present even before the disorder out-set. Although evidence suggests that this deficit may be not specific to faces, further evidence on this question is necessary, in particularly more ecological studies including context and body processing.

'What is more familiar than I? Self, other and familiarity in schizophrenia

BACKGROUND

Familiarity disorders (FDs) critically impact social cognition in persons with schizophrenia. FDs can affect both relationships with people familiar to the patient and the patient's relationship with himself, in the case of a self-disorder. Skin conductance response (SCR) studies have shown that familiar and unknown faces elicit the same emotional response in persons with schizophrenia with FD. Moreover, in control subjects, one's own face and familiar faces have been shown to activate strongly overlapping neural networks, suggesting common processing. The aim of the present study was to determine whether the mechanisms involved in processing one's own and familiar faces are similarly impaired in persons with schizophrenia, suggesting a link between them.

METHOD

Twenty-eight persons with schizophrenia were compared with twenty control subjects. Three face conditions were used: specific familiar, self and unknown. The task was to indicate the gender of the faces presented randomly on a screen during SCR recording. Face recognition was evaluated afterwards.

RESULTS

Control subjects exhibited similar SCRs for the familiar and self-conditions, which were higher than the responses elicited by the unknown condition, whereas persons with schizophrenia exhibited no significant differences between the three conditions.

CONCLUSION

Persons with schizophrenia have a core defect of both self and familiarity that is emphasised by the lack of an increased SCR upon presentation with either self or familiar stimuli. Familiarity with specific familiar faces and one's own face may be driven by the same mechanism. This perturbation may predispose persons with schizophrenia to delusions and, in particular, to general familiarity disorder.

Early visual processing deficits in patients with schizophrenia during spatial frequency-dependent facial affect processing

Abnormal facial emotion recognition is considered as one of the key symptoms of schizophrenia. Only few studies have considered deficits in the spatial frequency (SF)-dependent visual pathway leading to abnormal facial emotion recognition in schizophrenia. Twenty-one patients with schizophrenia and 19 matched healthy controls (HC) were recruited for this study. Event-related potentials (ERP) were measured during presentation of SF-modulated face stimuli and their source imaging was analyzed. The patients showed reduced P100 amplitude for low-spatial frequency (LSF) pictures of fearful faces compared with the HC group. The P100 amplitude for high-spatial frequency (HSF) pictures of neutral faces was increased in the schizophrenia group, but not in the HC group. The neural source activities of the LSF fearful faces and HSF neutral faces led to hypo- and hyperactivation of the frontal lobe of subjects from the schizophrenia group and HC group, respectively. In addition, patients with schizophrenia showed enhanced N170 activation in the right hemisphere in the LSF condition, while the HC group did not. Our results suggest that deficits in the LSF-dependent visual pathway, which involves magnocellular neurons, impair early visual processing leading to dysfunctional facial emotion recognition in schizophrenia. Moreover, it suggests impaired bottom-up processing rather than top-down dysfunction for facial emotion recognition in these patients.

Meta-analysis of face processing event-related potentials in schizophrenia

BACKGROUND

Schizophrenia is associated with impaired face processing. N170 and N250 are two event-related potentials that have been studied in relation to face processing in schizophrenia, but the results have been mixed. The aim of this article was to conduct a meta-analysis of N170 and N250 in schizophrenia to evaluate trends and resolve the inconsistencies.

METHODS

Twenty-one studies of N170 (n = 438 schizophrenia patients, n = 418 control subjects) and six studies of N250 (n = 149 schizophrenia patients, n = 151 control subjects) were evaluated. Hedges' g was calculated for each study, and the overall weighted mean effect size (ES) was calculated for N170 and N250. Homogeneity of the ES distributions, potential publication bias, and impact of potential moderators were also assessed.

RESULTS

The amplitude of both N170 and N250 to face stimuli was smaller in patients than control subjects (N170 ES = .64; N250 ES = .49; ps < .001). The distributions of the ES were homogeneous (ps > .90), and there was no indication of a publication bias. We found no significant effect of task requirements regarding judgments of the face stimuli. Moreover, we found no significant difference between the ES for N170 and N250.

CONCLUSIONS

Though findings of individual studies have been mixed, the results of the meta-analysis strongly support disruption of N170 and N250 in schizophrenia. The comparable effect sizes across the two waveforms suggest that the well-established behavioral deficit in face emotion processing is mirrored in an underlying neural impairment for processing faces.

Neural processing of facial expressions of emotion in first onset psychosis

Schizophrenia is characterized by deficits in face and facial emotion processing. This is the first study using event-related potentials (ERPs) to investigate the corresponding neural activation in first onset psychosis. ERPs for 108 first onset psychosis participants and 108 matched healthy controls were recorded while they viewed facial expressions. Group differences on general (neutral) face processing and emotional valence were examined under both unmasked (conscious) and backward-masked (nonconscious implicit) conditions over frontal and temporo-occipital regions. Clinical significance was assessed by comparing diagnoses and correlating ERPs with symptoms. During general face processing, patients showed reduced activation within 70 ms and exaggerated later processing from 160 ms over the frontal region, with a negative shift in voltage over left temporal and occipital regions across the time course. In addition, from 70 ms onwards, patients showed a positive shift in voltage for disgust whereas controls showed a negative shift in voltage for fear and anger (both compared to happy) over temporo-occipital regions. Effects were related to disorganization and depression symptoms and (preliminarily) were apparent across psychotic diagnoses. These results suggest that first onset psychosis is characterized by general as well as emotion-specific face processing impairments from the earliest, automatic processing period.

The N170 and face perception in psychiatric and neurological disorders: A systematic review

OBJECTIVE

To systematically evaluate evidence for configural and affective face processing abnormalities as measured by the N170 and Vertex Positive Potential (VPP) event-related potential components, and analogous M170 magnetoencephalography (MEG) component, in neurological and psychiatric disorders.

METHODS

1251 unique articles were identified using PsychINFO and PubMed databases. Sixty-seven studies were selected for review, which employed various tasks to measure the N170, M170 or VPP; the 13 neurological/psychiatric conditions were Attention-Deficit Hyperactivity Disorder (ADHD), Alcohol Dependence, Alzheimer's Disease, Autism Spectrum Disorders (ASDs), Bipolar Disorder, Bulimia Nervosa, Fibromyalgia, Huntington's Disease, Major Depressive Disorder, Parkinson's Disease, Prosopagnosia, Schizophrenia and Social Phobia.

RESULTS

Smaller N170 and VPP amplitudes to faces compared to healthy controls were consistently reported in Schizophrenia but not in ASDs. In Schizophrenia N170 and VPP measures were not correlated with clinical symptoms. Findings from other disorders were highly inconsistent; however, reported group differences were almost always smaller amplitudes or slower latencies to emotional faces in disordered groups regardless of diagnosis.

CONCLUSIONS

Results suggest that N170/VPP abnormalities index non-specific facial affect processing dysfunction in these neurological and psychiatric conditions, reflecting social impairments being broadly characteristic of these groups.

SIGNIFICANCE

The N170 and analogous components hold promise as diagnostic and treatment monitoring biomarkers for social dysfunction.

Role of visual integration in gaze perception and emotional intelligence in schizophrenia

BACKGROUND

Individuals with schizophrenia demonstrate a wide range of social cognitive deficits that significantly compromise functioning. Early visual processing is frequently disrupted in schizophrenia, and growing evidence suggests a role of perceptual dysfunctions in socioemotional functioning in the disorder. This study examined visual integration (the ability to effectively integrate individual, local visual features into a holistic representation), a target construct of basic perception identified by the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia initiative, and its relationship with eye- contact perception and emotional intelligence in schizophrenia.

METHODS

Twenty-nine participants with schizophrenia (SCZ) and 23 healthy controls (HC) completed tasks measuring visual integration (Coherent Motion Task, Contour Integration Task), an eye-contact perception task, and a measure of emotional intelligence.

RESULTS

SCZ participants showed compromised visual integration as suggested by poorer performance on the Contour Integration Task relative to HC. Visual integration was a significant predictor of eye-contact perception and emotional intelligence among SCZ. The amounts of variances in these 2 social cognitive areas accounted for by visual integration were comparable to and overlapped with those accounted for by the diagnosis of schizophrenia.

CONCLUSIONS

Individuals with schizophrenia showed compromised visual integration, and this may play a significant role in the observed deficits in higher level processing of social information in the disorder.

Neurophysiological correlates of configural face processing in schizotypy

BACKGROUND

Face processing impairment in schizophrenia appears to be underpinned by poor configural (as opposed to feature-based) processing; however, few studies have sought to characterize this impairment electrophysiologically. Given the sensitivity of event-related potentials to antipsychotic medications, and the potential for neurophysiological abnormalities to serve as vulnerability markers for schizophrenia, a handful of studies have investigated early visual P100 and face-selective N170 in "at risk" populations. However, this is the first known neurophysiological investigation of configural face processing in a non-clinical schizotypal sample.

METHODS

Using stimuli designed to engage configural processing in face perception (upright and inverted Mooney and photographic faces), P100 and N170 components were recorded in healthy individuals characterized by high (N = 14) and low (N = 14) schizotypal traits according to the Oxford-Liverpool Inventory of Feelings and Experiences.

RESULTS

High schizotypes showed significantly reduced N170 amplitudes to inverted photographic faces. Typical N170 latency and amplitude inversion effects (delayed and enhanced N170 to inverted relative to upright photographic faces, and enhanced amplitude to upright versus inverted Mooney faces), were demonstrated by low, but not high, schizotypes. No group differences were shown for P100 analyses.

CONCLUSIONS

The findings suggest that neurophysiological deficits in processing facial configurations (N170) are apparent in schizotypy, while the early sensory processing (P100) of faces appears intact. This work adds to the mounting evidence for analogous neural processing anomalies at the healthy end of the psychosis continuum.

Familiarity and face emotion recognition in patients with schizophrenia

OBJECTIVE

To assess the emotion recognition in familiar and unknown faces in a sample of schizophrenic patients and healthy controls.

METHODS

Face emotion recognition of 18 outpatients diagnosed with schizophrenia (DSM-IVTR) and 18 healthy volunteers was assessed with two Emotion Recognition Tasks using familiar faces and unknown faces. Each subject was accompanied by 4 familiar people (parents, siblings or friends), which were photographed by expressing the 6 Ekman's basic emotions. Face emotion recognition in familiar faces was assessed with this ad hoc instrument. In each case, the patient scored (from 1 to 10) the subjective familiarity and affective valence corresponding to each person.

RESULTS

Patients with schizophrenia not only showed a deficit in the recognition of emotions on unknown faces (p=.01), but they also showed an even more pronounced deficit on familiar faces (p=.001). Controls had a similar success rate in the unknown faces task (mean: 18 +/- 2.2) and the familiar face task (mean: 17.4 +/- 3). However, patients had a significantly lower score in the familiar faces task (mean: 13.2 +/- 3.8) than in the unknown faces task (mean: 16 +/- 2.4; p<.05). In both tests, the highest number of errors was with emotions of anger and fear. Subjectively, the patient group showed a lower level of familiarity and emotional valence to their respective relatives (p<.01).

CONCLUSIONS

The sense of familiarity may be a factor involved in the face emotion recognition and it may be disturbed in schizophrenia.