Diminished facial expression despite the existence of pleasant emotional experience in schizophrenia

Measuring facial expression of emotion

Research into emotions has increased in recent decades, especially on the subject of recognition of emotions. However, studies of the facial expressions of emotion were compromised by technical problems with visible video analysis and electromyography in experimental settings. These have only recently been overcome. There have been new developments in the field of automated computerized facial recognition; allowing real-time identification of facial expression in social environments. This review addresses three approaches to measuring facial expression of emotion and describes their specific contributions to understanding emotion in the healthy population and in persons with mental illness. Despite recent progress, studies on human emotions have been hindered by the lack of consensus on an emotion theory suited to examining the dynamic aspects of emotion and its expression. Studying expression of emotion in patients with mental health conditions for diagnostic and therapeutic purposes will profit from theoretical and methodological progress.

Mirroring the self: testing neurophysiological correlates of disturbed self-experience in schizophrenia spectrum

BACKGROUND

Self-disorders (SDs) have been described as a core schizophrenia spectrum vulnerability phenotype, both in classic and contemporary psychopathological literature. However, such a core phenotype has not yet been investigated adopting a trans-domain approach that combines the phenomenological and the neurophysiological levels of analysis. The aim of this study is to investigate the relation between SDs and subtle, schizophrenia-specific impairments of emotional resonance that are supposed to reflect abnormalities in the mirror neurons mechanism. Specifically, we tested whether electromyographic response to emotional stimuli (i.e. a proxy for subtle changes in facial mimicry and related motor resonance mechanisms) would predict the occurrence of anomalous subjective experiences (i.e. SDs).

SAMPLING AND METHODS

Eighteen schizophrenia spectrum (SzSp) patients underwent a comprehensive psychopathological examination and were contextually tested with a multimodal paradigm, recording facial electromyographic activity of muscles in response to positive and negative emotional stimuli. Experiential anomalies were explored with the Bonn Scale for the Assessment of Basic Symptoms (BSABS) and then condensed into rational subscales mapping SzSp anomalous self-experiences.

RESULTS

SzSp patients showed an imbalance in emotional motor resonance with a selective bias toward negative stimuli, as well as a multisensory integration impairment. Multiple regression analysis showed that electromyographic facial reactions in response to negative stimuli presented in auditory modality specifically and strongly correlated with SD subscore.

CONCLUSIONS

The study confirms the potential of SDs as target phenotype for neurobiological research and encourages research into disturbed motor/emotional resonance as possible body-level correlate of disturbed subjective experiences in SzSp.

Dimensional information-theoretic measurement of facial emotion expressions in schizophrenia

Altered facial expressions of emotions are characteristic impairments in schizophrenia. Ratings of affect have traditionally been limited to clinical rating scales and facial muscle movement analysis, which require extensive training and have limitations based on methodology and ecological validity. To improve reliable assessment of dynamic facial expression changes, we have developed automated measurements of facial emotion expressions based on information-theoretic measures of expressivity of ambiguity and distinctiveness of facial expressions. These measures were examined in matched groups of persons with schizophrenia (n = 28) and healthy controls (n = 26) who underwent video acquisition to assess expressivity of basic emotions (happiness, sadness, anger, fear, and disgust) in evoked conditions. Persons with schizophrenia scored higher on ambiguity, the measure of conditional entropy within the expression of a single emotion, and they scored lower on distinctiveness, the measure of mutual information across expressions of different emotions. The automated measures compared favorably with observer-based ratings. This method can be applied for delineating dynamic emotional expressivity in healthy and clinical populations.

Facial reactions in response to dynamic emotional stimuli in different modalities in patients suffering from schizophrenia: a behavioral and EMG study

Emotional facial expression is an important low-level mechanism contributing to the experience of empathy, thereby lying at the core of social interaction. Schizophrenia is associated with pervasive social cognitive impairments, including emotional processing of facial expressions. In this study we test a novel paradigm in order to investigate the evaluation of the emotional content of perceived emotions presented through dynamic expressive stimuli, facial mimicry evoked by the same stimuli, and their functional relation. Fifteen healthy controls and 15 patients diagnosed with schizophrenia were presented with stimuli portraying positive (laugh), negative (cry) and neutral (control) emotional stimuli in visual, auditory modalities in isolation, and congruently or incongruently associated. Participants where requested to recognize and quantitatively rate the emotional value of the perceived stimuli, while electromyographic activity of Corrugator and Zygomaticus muscles was recorded. All participants correctly judged the perceived emotional stimuli and prioritized the visual over the auditory modality in identifying the emotion when they were incongruently associated (Audio-Visual Incongruent condition). The neutral emotional stimuli did not evoke any muscle responses and were judged by all participants as emotionally neutral. Control group responded with rapid and congruent mimicry to emotional stimuli, and in Incongruent condition muscle responses were driven by what participants saw rather than by what they heard. Patient group showed a similar pattern only with respect to negative stimuli, whereas showed a lack of or a non-specific Zygomaticus response when positive stimuli were presented. Finally, we found that only patients with reduced facial mimicry (Internalizers) judged both positive and negative emotions as significantly more neutral than controls. The relevance of these findings for studying emotional deficits in schizophrenia is discussed.

Self-reported empathic abilities in schizophrenia: a longitudinal perspective

To study the effect of illness course on the subjective experience of empathy, we investigated the Interpersonal Reactivity Index in schizophrenia and controls over 3 years. We found stable IRI data in both groups and a stable positive correlation of the subscale 'Personal distress' with the PANSS negative scale.

Cognition-emotion dysinteraction in schizophrenia

Evolving theories of schizophrenia emphasize a "disconnection" in distributed fronto-striatal-limbic neural systems, which may give rise to breakdowns in cognition and emotional function. We discuss these diverse domains of function from the perspective of disrupted neural circuits involved in "cold" cognitive vs. "hot" affective operations and the interplay between these processes. We focus on three research areas that highlight cognition-emotion dysinteractions in schizophrenia: First, we discuss the role of cognitive deficits in the "maintenance" of emotional information. We review recent evidence suggesting that motivational abnormalities in schizophrenia may in part arise due to a disrupted ability to "maintain" affective information over time. Here, dysfunction in a prototypical "cold" cognitive operation may result in "affective" deficits in schizophrenia. Second, we discuss abnormalities in the detection and ascription of salience, manifest as excessive processing of non-emotional stimuli and inappropriate distractibility. We review emerging evidence suggesting deficits in some, but not other, specific emotional processes in schizophrenia - namely an intact ability to perceive emotion "in-the-moment" but poor prospective valuation of stimuli and heightened reactivity to stimuli that ought to be filtered. Third, we discuss abnormalities in learning mechanisms that may give rise to delusions, the fixed, false, and often emotionally charged beliefs that accompany psychosis. We highlight the role of affect in aberrant belief formation, mostly ignored by current theoretical models. Together, we attempt to provide a consilient overview for how breakdowns in neural systems underlying affect and cognition in psychosis interact across symptom domains. We conclude with a brief treatment of the neurobiology of schizophrenia and the need to close our explanatory gap between cellular-level hypotheses and complex behavioral symptoms observed in this illness.

Cognition-emotion dysinteraction in schizophrenia

Evolving theories of schizophrenia emphasize a "disconnection" in distributed fronto-striatal-limbic neural systems, which may give rise to breakdowns in cognition and emotional function. We discuss these diverse domains of function from the perspective of disrupted neural circuits involved in "cold" cognitive vs. "hot" affective operations and the interplay between these processes. We focus on three research areas that highlight cognition-emotion dysinteractions in schizophrenia: First, we discuss the role of cognitive deficits in the "maintenance" of emotional information. We review recent evidence suggesting that motivational abnormalities in schizophrenia may in part arise due to a disrupted ability to "maintain" affective information over time. Here, dysfunction in a prototypical "cold" cognitive operation may result in "affective" deficits in schizophrenia. Second, we discuss abnormalities in the detection and ascription of salience, manifest as excessive processing of non-emotional stimuli and inappropriate distractibility. We review emerging evidence suggesting deficits in some, but not other, specific emotional processes in schizophrenia - namely an intact ability to perceive emotion "in-the-moment" but poor prospective valuation of stimuli and heightened reactivity to stimuli that ought to be filtered. Third, we discuss abnormalities in learning mechanisms that may give rise to delusions, the fixed, false, and often emotionally charged beliefs that accompany psychosis. We highlight the role of affect in aberrant belief formation, mostly ignored by current theoretical models. Together, we attempt to provide a consilient overview for how breakdowns in neural systems underlying affect and cognition in psychosis interact across symptom domains. We conclude with a brief treatment of the neurobiology of schizophrenia and the need to close our explanatory gap between cellular-level hypotheses and complex behavioral symptoms observed in this illness.

Emotion effects on attention, amygdala activation, and functional connectivity in schizophrenia

Emotional abnormalities are a critical clinical feature of schizophrenia (SCZ), but complete understanding of their underlying neuropathology is lacking. Numerous studies have examined amygdala activation in response to affective stimuli in SCZ, but no consensus has emerged. However, behavioral studies examining 'in-the-moment' processing of affect have suggested intact emotional processing in SCZ. To examine which aspects of emotional processing may be impaired in SCZ, we combined behavior and neuroimaging to investigate effects of aversive stimuli during minimal cognitive engagement, at the level of behavior, amygdala recruitment, and its whole-brain task-based functional connectivity (tb-fcMRI) because impairments may manifest when examining across-region functional integration. Twenty-eight patients and 24 matched controls underwent rapid event-related fMRI at 3 T while performing a simple perceptual decision task with negative or neutral distraction. We examined perceptual decision slowing, amygdala activation, and whole-brain amygdala tb-fcMRI, while ensuring group signal-to-noise profile matching. Following scanning, subjects rated all images for experienced arousal and valence. No significant group differences emerged for negative vs neutral reaction time, emotional ratings across groups, or amygdala activation. However, even in the absence of behavioral or activation differences, SCZ subjects demonstrated significantly weaker amygdala-prefrontal cortical coupling, specifically during negative distraction. Whereas in-the-moment perception, behavioral response, and amygdala recruitment to negative stimuli during minimal cognitive load seem to be intact, there is evidence of aberrant amygdala-prefrontal integration in SCZ subjects. Such abnormalities may prove critical for understanding disturbances in patients' ability to use affective cues when guiding higher level cognitive processes needed in social interactions.

Amygdala recruitment in schizophrenia in response to aversive emotional material: a meta-analysis of neuroimaging studies

Emotional dysfunction has long been established as a critical clinical feature of schizophrenia. In the past decade, there has been extensive work examining the potential contribution of abnormal amygdala activation to this dysfunction in patients with schizophrenia. A number of studies have demonstrated under-recruitment of the amygdala in response to emotional stimuli, while others have shown intact recruitment of this region. To date, there have been few attempts to synthesize this literature using quantitative criteria or to use a formal meta-analytic approach to examine which variables may moderate the magnitude of between-group differences in amygdala activation in response to aversive emotional stimuli. We conducted a meta-analysis of amygdala activation in patients with schizophrenia, using a bootstrapping approach to investigate: (a) evidence for amygdala under-recruitment in schizophrenia and (b) variables that may moderate the magnitude of between-group differences in amygdala activation. We demonstrate that patients with schizophrenia show statistically significant, but modest, under-recruitment of bilateral amygdala (mean effect size = -0.20 SD). However, present findings indicate that this under-recruitment is dependent on the use of a neutral vs emotion interaction contrast and is not apparent if amygdala activation by patients and controls is evaluated in a negative emotional condition only.

Neural correlates of emotional recognition memory in schizophrenia: effects of valence and arousal

Schizophrenia patients are often impaired in their memory for emotional events compared with healthy subjects. Investigations of the neural correlates of emotional memory in schizophrenia patients are scarce in the literature. The present study aimed to compare cerebral activations in schizophrenia patients and healthy controls during memory retrieval of emotional images that varied in both valence and arousal. In a study with functional magnetic resonance imaging, 37 schizophrenia patients were compared with 37 healthy participants while performing a yes/no recognition paradigm with positive, negative (differing in arousal intensity) and neutral images. Schizophrenia patients performed worse than healthy controls in all experimental conditions. They showed less cerebral activation in limbic and prefrontal regions than controls during retrieval of negatively valenced stimuli, but had a similar pattern of brain activation compared with controls during retrieval of positively valenced stimuli (particularly in the high arousal condition) in the cerebellum, temporal lobe and prefrontal cortex. Both groups demonstrated increased brain activations in the high relative to low arousing conditions. Our results suggest atypical brain function during retrieval of negative pictures, but intact functional circuitry of positive affect during episodic memory retrieval in schizophrenia patients. The arousal data revealed that schizophrenia patients closely resemble the control group at both the behavioral and neurofunctional level.

Negative and nonemotional interference with visual working memory in schizophrenia

BACKGROUND

Schizophrenia (SCZ) results in abnormalities affecting both working memory (WM) and emotional processing. Prior work suggests that individuals with SCZ exhibit increased effects of distraction on WM-a deficit that might be exacerbated via emotional interference. However, no study characterized effects of negative and nonemotional interference on visual WM in SCZ with functional magnetic resonance imaging. We tested the hypothesis that SCZ is associated with a general inability to filter distraction versus a specific deficit in the ability to filter aversive emotional distraction.

METHODS

Twenty-eight patients with DSM-IV-diagnosed SCZ and 24 matched control subjects underwent blood-oxygen-level-dependent imaging with functional magnetic resonance imaging at 3-T. Subjects performed a modified delayed-response visual WM task faced with affectively negative, neutral, or task-related interference.

RESULTS

Control subjects showed maximal interference after aversive distraction, whereas patients were more distracted irrespective of interference type. Importantly, aversive distraction resulted in similar across-group activation in regions previously showing robust effects of negative interference. Conversely, after any distraction, patients showed reduced blood-oxygen-level-dependent activity in prefrontal regions previously implicated in filtering interference. Particularly when distracted, SCZ subjects exhibited aberrant responses to nonemotional distraction across posterior cortical regions.

CONCLUSIONS

Results suggest that patients fail to deploy activity associated with distracter filtering exhibited by control subjects. Although SCZ subjects show similar responses to aversive interference across certain regions, there is also evidence of enhanced responses to nonemotional inputs. These results are consistent with a general deficit in the ability of patients to filter distraction, which might be in line with aberrant salience processing as a pathophysiological mechanism in SCZ.

Emotional experience in patients with schizophrenia revisited: meta-analysis of laboratory studies

Our understanding of the emotion deficits in schizophrenia is limited. Findings from studies employing trait emotion instruments suggest that patients have attenuated levels of positive emotion (ie, anhedonia) and increased levels of negative emotion. Conversely, patients and controls have not statistically differed in their subjective reactions to positive or negative valenced stimuli in most laboratory studies to date. Further obfuscating this issue is the fact that many of these laboratory studies are underpowered and a handful of emotion induction studies have found evidence of anhedonia. We conducted a meta-analysis of 26 published studies employing laboratory emotion induction procedures in patients with schizophrenia and healthy controls. Patients did not differ from controls when strictly rating their subjective hedonic reactions to the stimuli. However, they reported experiencing relatively strong aversion to both positive and neutral stimuli (Hedges D = .72 and .64, respectively). These findings were not the result of demonstrable sample or methodological differences across studies. Patients' ability to experience hedonic emotion is preserved, although they also show relatively strong, simultaneously occurring aversive emotion when processing laboratory stimuli considered by others to be pleasant or neutral.

Aberrantly flattened responsivity to emotional pictures in paranoid schizophrenia

To investigate the nature of emotional experience in schizophrenia, we examined emotional responses to affective stimuli. Twenty-one outpatients with schizophrenia (9 paranoid, 12 nonparanoid) and 20 normal controls rated the arousal and valence that they experienced from the presentation of 60 pictures. Schizophrenia patients displayed less emotional responsivity to the positive stimuli and they displayed diverse responsivity to the negative stimuli, which depended upon arousal level. Further analysis, using schizophrenia subtype, indicated that nonparanoid patients reported increased negative responsivity and decreased positive responsivity, regardless of arousal level. However, paranoid schizophrenia patients showed enhanced self-reported experiences of emotion to the low arousing stimuli and diminished responsivity to the high arousing stimuli. This pattern was robust to the negative stimuli. These findings suggest that paranoid schizophrenia patients might suffer from aberrantly flattened responses to negative emotional stimuli, and that this may account for paranoid tendency and secondary social isolation in paranoid schizophrenia.

A review of emotion deficits in schizophrenia

Emotion deficits in schizophrenia have been described since the time of Kraepelin. However, no comprehensive review of clinical emotion studies has ever been conducted, in this work, studies that used diagnostic criteria and were published in English were selected from an extensive PubMed search. Fifty-five studies on emotion expression repeatedly showed that individuals with schizophrenia (IWSs) display fewer overt expressions than non patient comparison subjects (NCSs) in verbal, facial, and acoustic channels. No clear differences were found between IWSs and depressed subjects. Sixty-nine studies examined emotion experience in schizophrenia. IWSs report higher anhedonia, and they tend to show more negative emotions in real-life event studies. In evocative studies, they report a similar degree of pleasantness and a similar or higher degree of unpleasantness. From 110 studies, ii can be concluded that emotion recognition is impaired in schizophrenia in all channels. These deficits in social perception are correlated with neurocognitive deficits and some social skills. IWSs show dysfunction in the three domains of emotion expression, emotion experience, and emotion recognition, and these dysfunctions appear to be independent of each other across domains. These deficits in basic emotion processing may be linked to psychopathology and functional outcomes.

Brain activity during emotionally negative pictures in schizophrenia with and without flat affect: an fMRI study

The aim of this functional magnetic resonance imaging (fMRI) study was to compare regional brain activity in schizophrenia subjects with (FA+) and without (FA-) flat affect during the viewing of emotionally negative pictures. Thirteen FA+ subjects and 11 FA- subjects were scanned while being presented with a series of emotionally negative and neutral pictures. Experientially, the viewing of the negative pictures induced a negative emotional state whose intensity was significantly greater in the FA- group than in the FA+ group. Neurally, the Negative minus Neutral contrast revealed, in the FA- group, significant loci of activation in the midbrain, pons, anterior cingulate cortex, insula, ventrolateral orbitofrontal cortex, anterior temporal pole, amygdala, medial prefrontal cortex, and extrastriate visual cortex. In the FA+ group, this contrast produced significant loci of activation in the midbrain, pons, anterior temporal pole, and extrastriate visual cortex. When the brain activity measured in the FA+ group was subtracted from that measured in the FA- group, only the lingual gyrus was significantly activated. Perhaps in FA+ subjects an amygdaloid malfunction rendered the amygdala unable to correctly evaluate the emotional meaning of the pictures presented, thus preventing effective connectivity linking the amygdala to the brain regions implicated in the physiological and experiential dimensions of emotion. Alternatively, a disturbance of effective connectivity in the neural networks linking the midbrain and the medial prefrontal system may have been responsible for the quasi absence of emotional reaction in FA+ subjects, and the abnormal functioning of the medial prefrontal cortex and anterior cingulate cortex in the FA+ group.