Impaired emotion perception in schizophrenia: a differential deficit

We investigated previously reported contradictory findings regarding the nature of deficits in emotion perception among patients with schizophrenia. Some studies have concluded that such deficits are due to a generalized impairment in visual processing of faces, while others have found it to be restricted to facial emotional expressions. We examined 37 patients and 32 healthy controls, matched on age and education, using three computerized tests: matching facial identity, matching facial emotional expressions, and discrimination of subtle differences in the valence of facial emotional expressions. Our results showed impaired matching of emotions in patients with schizophrenia. This impairment did not manifest on tasks that depended on perceiving the identity of faces or cues of the relative valence of facial emotional expressions. Our findings support the differential deficit hypothesis of emotion perception in schizophrenia.     

Impairment in the specificity of emotion processing in schizophrenia

OBJECTIVE: Deficits in emotion processing are a hallmark of schizophrenia, with consequences for social functioning and subjective well-being. However, their specificity and characteristics have not been ascertained psychometrically. The authors' purpose was to examine a differential deficit for processing emotional facets of the face compared to judgment of nonemotional features (age) and facial memory. The authors also sought to establish whether the deficit affects sensitivity or specificity of performance. METHOD: Participants were 20 patients with schizophrenia and 20 healthy subjects matched for age, gender, and parental education. The authors examined emotional discrimination abilities compared to age discrimination and recognition memory for faces with standardized faces displaying the universal emotions of happiness, sadness, anger, and fear. Percent correct in each condition and for each emotion were assessed as well as sensitivity (correct identification of a target emotion) and specificity (correct rejection of a nontarget emotion) for emotion recognition. RESULTS: Patients with schizophrenia were differentially impaired in the discrimination of emotional aspects of facial expressions compared to nonemotional aspects and memory. Within the emotional task, patients showed differential impairment in specificity and insensitivity to the emotion displayed. CONCLUSIONS: When identical stimuli were used across tasks, differential impairment was seen in patients with schizophrenia for processing emotional faces, although the nonemotional task proved harder for both groups. Impairment in the specificity of emotion identification may lead to misunderstanding of social communication and may underlie difficulties in social adjustment experienced by people with schizophrenia. Emotion discrimination tests could augment the neurobehavioral evaluation of patients.     

Symptom Correlates of Static and Dynamic Facial Affect Processing in Schizophrenia: Evidence of a Double Dissociation?

Schizophrenia patients have been shown to be compromised in their ability to recognize facial emotion. This deficit has been shown to be related to negative symptoms severity. However, to date, most studies have used static rather than dynamic depictions of faces. Nineteen patients with schizophrenia were compared with seventeen controls on 2 tasks; the first involving the discrimination of facial identity, emotion, and butterfly wings; the second testing emotion recognition using both static and dynamic stimuli. In the first task, the patients performed more poorly than controls for emotion discrimination only, confirming a specific deficit in facial emotion recognition. In the second task, patients performed more poorly in both static and dynamic facial emotion processing. An interesting pattern of associations suggestive of a possible double dissociation emerged in relation to correlations with symptom ratings: high negative symptom ratings were associated with poorer recognition of static displays of emotion, whereas high positive symptom ratings were associated with poorer recognition of dynamic displays of emotion. However, while the strength of associations between negative symptom ratings and accuracy during static and dynamic facial emotion processing was significantly different, those between positive symptom ratings and task performance were not. The results confirm a facial emotion-processing deficit in schizophrenia using more ecologically valid dynamic expressions of emotion. The pattern of findings may reflect differential patterns of cortical dysfunction associated with negative and positive symptoms of schizophrenia in the context of differential neural mechanisms for the processing of static and dynamic displays of facial emotion.     

Aging and visual motion discrimination in normal adults and schizophrenia patients

Motion perception is impaired in many neuropathological conditions, including schizophrenia. Motion perception also declines in the course of normal aging. In this study, we ask whether aging is an additive factor in the motion-discrimination deficits of schizophrenia patients. We examined motion perception in schizophrenia patients (n=44) and non-psychiatric controls (n=40) whose ages ranged from 18 to 55. The tasks included velocity discrimination and contrast detection. Thresholds for each of the two tasks were determined for each subject using psychophysical methods. Schizophrenia patients showed significantly increased thresholds (degraded performance) for velocity discrimination compared with the controls. Degraded performance in patients was not related to age. In controls, however, velocity discrimination thresholds were significantly increased beginning by age 45. Performance on a contrast-detection task, which does not require precise discrimination of motion signals, was not significantly affected by age in either group. Aging, even in its early stages, degrades motion discrimination in normal adults. Aging, however, does not adversely affect motion-discrimination deficits in schizophrenia patients through age 55. A similar motion-discrimination deficit in schizophrenia patients and aging normal adults suggests that the mechanisms underlying motion processing in schizophrenia and normal aging may be associated.     

Automatic affective processing impairments in patients with deficit syndrome schizophrenia

Affective impairments were examined in patients with and without deficit syndrome schizophrenia. Two Emotional Stroop tasks designed to measure automatic processing of emotional information were administered to deficit (n=15) and non-deficit syndrome (n=26) schizophrenia patients classified according to the Schedule for the Deficit Syndrome, and matched non-patient control subjects (n=22). In comparison to non-deficit patients and controls, deficit syndrome patients demonstrated a lack of attention bias for positive information, and an elevated attentional lingering effect for negative information. These findings suggest that positive information fails to automatically capture attention of deficit syndrome patients, and that when negative information captures attention, it produces difficulty in disengagement Attentional abnormalities were significantly correlated with negative symptoms, such that more severe symptoms were associated with less attention bias for positive emotion and a greater lingering effect for negative information. Results are generally consistent with a mood-congruent processing abnormality and suggest that impaired automatic processing may be core to diminished emotional experience symptoms exhibited in deficit syndrome patients.     

Impairment of theory of mind in patients in remission following first episode of schizophrenia

Abstract The aim of this study was to investigate theory of mind (ToM) ability in patients in remission after the first episode of schizophrenia. A ToM task which contained four pictures was given to 30 patients with schizophrenia in remission and 30 matched healthy controls. Patients with schizophrenia in remission showed statistically significant impairment in the ToM tasks. ToM impairment was not correlated with psychiatric symptoms. Thus, ToM deficit in schizophrenia may be a trait marker.     

Clinical significance of sleep EEG abnormalities in chronic schizophrenia

This study aimed to investigate the relationship between measures of clinical symptom severity and sleep EEG parameters in a relatively diagnostically homogeneous group of patients with schizophrenia. We obtained sleep EEG data in 15 drug-free inpatients who met DSM-IV-R criteria for schizophrenia, undifferentiated type, with 15 age- and sex-matched normal controls over two consecutive night polysomnographic recordings. Clinical symptoms were assessed by the Positive and Negative Symptom Scale (PANSS) and Hamilton Rating Scale for Depression. Characteristic features of sleep disturbance were seen in patients with schizophrenia: profound difficulties in sleep initiation and maintenance, poor sleep efficiency, a slow wave sleep (SWS) deficit, and an increased REM density. SWS was inversely correlated with cognitive symptoms. REM density was inversely correlated with positive, cognitive, and emotional discomfort symptoms as well as PANSS total score. Our data demonstrate that drug-free patients with chronic undifferentiated type schizophrenia suffer from profound disturbances in sleep continuity and sleep architecture. Both the SWS deficit and cognitive impairment found in schizophrenics in this study may relate to similar underlying structural brain abnormalities.     

Early-onset schizophrenia is associated with impaired adolescent development of attentional capacity using the identical pairs continuous performance test

The authors examined performance on the Continuous Performance Test-Identical Pairs "numbers" task in adolescents with schizophrenia (n=59) and healthy controls (n=55). Adjusting for an estimate of premorbid intelligence and socioeconomic status, patients performed worse than normal controls on all three d' conditions (2-digit, 3-digit, 4-digit). However, there was a significant group-by-age-by-condition interaction (F[4,100]=4.69, p<.01) indicating an interaction between development and disease state. At the simplest level of the task (2-digit) the difference between patients with schizophrenia and controls was evident at all ages; while for the more difficult levels of the task (3-digit, 4-digit), differences between groups gradually increased across the tested age span (10 to 20 years of age). Premorbid social isolation was associated with worse attentional performance in patients, suggesting a relationship and continuity with negative symptoms. These data suggest that attentional differences in adolescents with schizophrenia are better captured by different tasks at different ages. The discrepant findings of attentional impairments reported in the literature for adolescents with schizophrenia could reflect the underlying etiological complexity of the disorder that may have a variable impact on involved brain regions and neurocognitive functioning.     

Deficit versus negative syndrome in schizophrenia: prediction of attentional impairment

Findings on neuropsychological associates of the negative syndrome of schizophrenia have been inconsistent. The "deficit syndrome," a reconceptualization of the negative syndrome, was developed in part to address this inconsistency. The purpose of this study was (1) to replicate previous findings relating the deficit syndrome to impairment of certain kinds of attentional abilities, and (2) to compare the negative and deficit syndromes in their associations with performance on tests of attention. Data from 40 individuals with schizophrenia were analyzed. Results provide evidence to suggest that impairment of certain attentional processes is associated with severity of deficit symptomatology, while impairment of other attentional processes is not. Moreover, the negative and deficit syndromes differed in their respective associations with attentional task performance at a trend level or above for five of seven tasks, suggesting that the negative and deficit syndromes do indeed have different underlying neuropsychological correlates.     

Inhibition in schizophrenia: association with auditory hallucinations

The study investigated whether auditory hallucinations (AH) in schizophrenia are linked to a deficit in inhibition. Two tasks assessing the intentional suppression of cognitive events-the Hayling Sentence Completion Test (HSCT) [Neuropsychologia 34 (1996) 263] and the Inhibition of Currently Irrelevant Memories Task (ICIM) [Nature Neuroscience 2 (1999) 677]-were administered to 42 patients with schizophrenia and 24 normal controls. Presence and severity of symptoms in the patient group were examined using the Positive and Negative Syndrome Scale (PANSS). Patients performed significantly worse on the measures of inhibition compared to controls. More importantly, among patients, significant positive correlations were obtained between an index of AH severity (defined as an increase in frequency of AH on PANSS) and the number of type A errors on the HSCT and errors in the last three runs of the ICIM. An increase in AH severity was, therefore, associated with increasingly impaired control of intentional inhibition. Furthermore, no significant correlations were found between these indices of inhibition and either negative, general or positive symptoms (excluding AH scores).     

Emotion recognition impairment is present early and is stable throughout the course of schizophrenia

Individuals with schizophrenia experience problems in the perception of emotion throughout the course of the disorder. Few studies have addressed the progression of the deficit over time. The present investigation explores face emotion recognition (FER) performance throughout the course of schizophrenia. The aim of the study was to test the hypotheses that: 1) FER impairment was present in ultra high-risk (putatively prodromal) individuals, and that 2) impairment was stable across the course of the illness. Forty-three individuals with a putative prodromal syndrome, 50 patients with first episode of schizophrenia, 44 patients with multi-episode schizophrenia and 86 unaffected healthy control subjects were assessed to examine emotion recognition ability. ANCOVA analysis adjusted for possible confounder factors and subsequent planned contrasts with healthy controls was undertaken. The results revealed deficits in recognition of sadness and disgust in prodromal individuals, and of all negative emotions in both first-episode and multi-episode patients. Furthermore, there were no significant differences between clinical groups. Within the framework of the neurodevelopmental model of schizophrenia, our results suggest the presence of emotional recognition impairment before the onset of full-blown psychosis. Moreover, the deficit remains stable over the course of illness, fitting the pattern of a vulnerability indicator in contrast to an indicator of chronicity or severity.     

Gaze direction determination in schizophrenia

It has been proposed that an impairment in gaze determination is responsible for the paranoid symptoms reported in schizophrenia. To address this, we examined the gaze discrimination system in schizophrenia. Thirty-two patients suffering from schizophrenia (20 patients with persecutory delusions and 12 patients without such delusions) were compared to 32 control subjects on two specific tasks. In the first task, the subjects had to determine whether 130 portraits were looking right or left. In the second task the subjects were asked to determine whether or not 130 portraits were looking at them.The absolute threshold of difference used to investigate the influence of instruction on gaze discrimination did not show any difference between patients with schizophrenia, whatever paranoid or not, and control subjects. Paranoid patients, as well as controls, displayed a significantly finer discrimination threshold in the right vs. left judgment than in the self vs. non-self judgment. Subjects with schizophrenia were able to discriminate gaze direction in the two tasks, but they took significantly more time in the task requiring to determine the presence or the absence of a mutual gaze contact than in the other one, whereas controls took the same duration to elicit both tasks. These data are consistent with those reporting that perceptual abilities are spared in schizophrenia while delusions are related to an impairment of a higher level of analysis.     

Brain activation during eye gaze discrimination in stable schizophrenia

OBJECTIVE: Earlier studies described gaze discrimination impairment in schizophrenia. The purpose of this study was to compare gaze discrimination abilities and associated brain activation in persons with stable schizophrenia and matched controls. METHODS: 13 schizophrenia and 12 healthy participants underwent a gaze discrimination task with face stimuli rotated at 0, 4 and 8 degrees deviation. During fMRI with BOLD imaging, subjects were asked to identify whether a face was making eye contact. Subject-level parameter estimates for BOLD signal change were entered into an orientation by group mixed effect repeated measures ANOVA. RESULTS: Gaze discrimination performance did not differ between groups. Patients showed decreased activation in areas of bilateral inferior frontal and occipital areas, and select temporo-limbic regions, including amygdala. Groups differed by activation patterns according to gaze deviation. In controls, faces with 4 degrees deviation produced higher activation in frontal and temporal regions. In patients, 0 degrees deviation produced increased activation in amygdala and areas of temporal neocortex. CONCLUSIONS: Despite similar gaze discrimination abilities, schizophrenia patients exhibit decreased brain activation in areas associated with executive, emotional and visual processing. Controls exhibited increased activation associated with the more difficult task in select frontal and temporal regions. Patients exhibited increased activation associated with direct gaze in temporal regions, which may relate to common symptoms.     

Emotional face processing deficit in schizophrenia: A replication study in a South African Xhosa population

Schizophrenia is associated with a deficit in the recognition of negative emotions from facial expressions. The present study examined the universality of this finding by studying facial expression recognition in African Xhosa population. Forty-four Xhosa patients with schizophrenia and forty healthy controls were tested with a computerized task requiring rapid perceptual discrimination of matched positive (i.e. happy), negative (i.e. angry), and neutral faces. Patients were equally accurate as controls in recognizing happy faces but showed a marked impairment in recognition of angry faces. The impairment was particularly pronounced for high-intensity (open-mouth) angry faces. Patients also exhibited more false happy and angry responses to neutral faces than controls. No correlation between level of education or illness duration and emotion recognition was found but the deficit in the recognition of negative emotions was more pronounced in familial compared to non-familial cases of schizophrenia. These findings suggest that the deficit in the recognition of negative facial expressions may constitute a universal neurocognitive marker of schizophrenia.     

Dissociation of cognitive from affective components of theory of mind in schizophrenia

Patients suffering from schizophrenia show impaired emotional and social behavior, such as misinterpretation of social situations and lack of theory of mind. However, there is conflicting evidence regarding their ability to perform on theory of mind tasks. Based on previous findings with patients suffering from prefrontal damage, the present study suggests that the behavioral deficit of schizophrenic patients may be due to impaired 'affective theory of mind' abilities, rather than to a general impairment in theory of mind. To test this hypothesis we assessed the ability of 22 schizophrenic patients and 55 age-matched healthy controls, to judge first and second order affective vs. cognitive mental state attribution, based on eye gaze. The relationships between negative and positive symptoms of schizophrenia, and affective and cognitive theory of mind were also assessed. Results indicated that while healthy controls made fewer errors on affective as compared to cognitive theory of mind conditions, schizophrenic patients showed a less prominent trend. Although the pattern of reaction time did not differ significantly between groups, the patients made significantly more errors in the affective conditions, as compared to controls. Furthermore, correlation analysis indicated that impaired affective theory of mind in these patients correlated with their level of negative symptoms. These results indicate that individuals with high level of negative symptoms of schizophrenia may demonstrate selective impairment in their ability to attribute affective mental states. These findings offer new insight into the affective facets of social behavior that may underlie the profound behavioral disturbances observed in schizophrenia.     

Historical,psychopathological, neurological,and neuropsychological aspects of deficit schizophrenia: a multicenter study

OBJECTIVE: This multicenter study aimed to verify whether the historical and psychopathological characteristics of a large group of patients with deficit schizophrenia were consistent with those reported in previous studies. The authors also tested the hypothesis that neurological and neuropsychological indices sensitive to frontoparietal dysfunction, but not those sensitive to temporal lobe dysfunction, are more impaired in patients with deficit schizophrenia than in those with non-deficit schizophrenia. METHOD: For each patient with deficit schizophrenia enrolled in the study, a matched subject with non-deficit schizophrenia was recruited. Historical, psychopathological, neurological, and neuropsychological evaluations were carried out for all patients. RESULTS: Patients with deficit schizophrenia, compared with patients with non-deficit schizophrenia, had a similar severity of positive symptoms and disorganization and less hostility. They had poorer premorbid adjustment during childhood and early adolescence and exhibited more impairment in general cognitive abilities. The deficit state was associated with impairment in sequencing of complex motor acts, which suggests frontoparietal dysfunction. CONCLUSIONS: Previous reports of differences in historical, psychopathological, and neuropsychological characteristics between patients with deficit schizophrenia and those with non-deficit schizophrenia were mostly supported by the present findings. Neurological findings suggest that frontoparietal functioning is more impaired in patients with deficit schizophrenia. Deficit schizophrenia might represent a neurodevelopmental subtype of schizophrenia in which significant behavioral and cognitive impairment since childhood compromises the development of basic capacities relevant to subsequent cognitive and social functioning.     

Flat affect in schizophrenia: relation to emotion processing and neurocognitive measures

Impaired emotional functioning in schizophrenia is a prominent clinical feature that manifests primarily as flat affect. Studies have examined the perception, experience, and expression of emotions in schizophrenia and reported normal ratings of experience but impaired affect identification. However, the relation between flat affect and performance on facial affect identification and cognitive tasks has not been systematically examined in relation to premorbid adjustment and clinical outcome. We report a prospective study of 63 patients with at least moderate severity of flat affect and 99 patients without flat affect, who were compared on functional domains, emotion processing tasks, and neurocognitive measures. Flat affect was more common in men and was associated with poorer premorbid adjustment, worse current quality of life, and worse outcome at 1-year follow-up. Patients overall performed more poorly on emotion processing tasks, one that required identification of happy and sad emotions and one that required differentiating among intensities within these emotions. They responded inaccurately yet faster than controls for the intensity differentiation task, suggesting a decomposition of the normal relation between accuracy and speed. Flat affect ratings, compared with other negative symptoms, uniquely predicted performance on emotion processing tasks. Patients with flat affect showed greater impairment in both emotion processing tasks, with the most pronounced impairment for the intensity differentiation task. However, the 2 patient groups did not differ in the neurocognitive profile except for verbal memory. We conclude that flat affect is an important clinical feature of schizophrenia that exacerbates the course of illness.     

Emotional Experience in Negative Symptoms of Schizophrenia—No Evidence for a Generalized Hedonic Deficit

Background: Deficits in emotion processing are thought to underlie the key negative symptoms flat affect and anhedonia observed in psychotic disorders. This study investigated emotional experience and social behavior in the realm of daily life in a sample of patients with schizophrenia and schizoaffective disorder, stratified by level of negative symptoms. Methods: Emotional experience and behavior of 149 patients with schizophrenia and schizoaffective disorder and 143 controls were explored using the Experience Sampling Method. Results: Patients reported lower levels of positive and higher levels of negative affect compared with controls. High negative symptom patients reported similar emotional stability and capacity to generate positive affect as controls, whereas low negative symptom patients reported increased instability. All participants displayed roughly comparable emotional responses to the company of other people. However, in comparison with controls, patients showed more social withdrawal and preference to be alone while in company, particularly the high negative symptom group. Conclusions: This study revealed no evidence for a generalized hedonic deficit in patients with psychotic spectrum disorders. Lower rather than higher levels of negative symptoms were associated with a pattern of emotional processing which was different from healthy controls.     

Impairment of odor hedonics in men with schizophrenia

OBJECTIVE: Olfactory deficits in patients with schizophrenia, including those of odor identification, detection threshold sensitivity, discrimination, and memory, have been well described. Deficits in emotional perception, processing, and experience have also been reported, with anhedonia being one of the core features. While anatomical connections testify to the relationship between olfaction and emotion, there has been little investigation of the hedonic properties of odors in schizophrenia. This study examined intensity and hedonic judgments in patients with schizophrenia to determine whether these functions were differentially impaired. METHOD: Suprathreshold scaling of odor intensity and pleasantness was acquired by using the Suprathreshold Amyl Acetate Odor Intensity and Odor Pleasantness Rating Test given to 30 patients (15 men and 15 women) with a DSM-IV diagnosis of schizophrenia and 30 age- and sex-matched healthy comparison subjects. RESULTS: Despite virtually identical ratings of odor intensity, male patients were impaired in the assignment of odor pleasantness to amyl acetate. This gender-specific diagnostic group difference was not explained by variability in symptom severity or negative/positive symptoms. The impact of smoking status and general cognitive impairment on this deficit was also insignificant. CONCLUSIONS: Findings reveal a gender-specific disruption in the ability to attribute appropriate hedonic valence to odors in male patients with schizophrenia. This difficulty in identifying the hedonic valence of odors, despite intact intensity ratings, is consistent with clinical observations of anhedonia and points to a neural substrate that might contribute to the emotional disturbances seen in patients with schizophrenia.     

Facial recognition deficits and cognition in schizophrenia

Previous investigations have found impaired recognition of facial affect and cognition in schizophrenia. We compared patients with schizophrenia and healthy control volunteers on computerized tasks of emotion recognition, to determine whether emotion processing deficits were correlated with neurocognitive performance. A Computerized Neuropsychological Test Battery (CNP) was administered to 40 patients (25 male, 15 female, mean age+/-S.D. 30.4+/-8.1) with schizophrenia (DSM-IV, 15 first episode and 25 chronically ill patients) treated with atypical neuroleptics and 43 healthy volunteers. A German version of the PENN Facial Discrimination, Differentiation and Memory Test, including happy, sad and neutral faces was used. Additionally, all patients were tested with a standard neuropsychological battery and rated for positive and negative symptoms. Patients with schizophrenia performed worse than control subjects on all emotion recognition tasks (p<0.01). We found higher error rates for discrimination of emotion in happy (p<0.02) and happy female faces (p<0.01), for differentiation of sad versus happy faces (p<0.001) and for facial memory (p<0.04). Poorer performance in emotion discrimination and facial memory correlated with severity of negative symptoms, abstraction-flexibility (p<0.001), verbal memory (p<0.01) and language processing (p<0.001). The study did not reveal a specific deficit for emotion recognition in schizophrenia. These findings lend support to the notion that difficulties in emotion recognition are associated in schizophrenia with key cognitive deficits.