Hemispheric functioning in paranoid and nonparanoid schizophrenia

Letter-naming and dot enumeration tasks, designed to elicit left and right hemisphere functioning, respectively, were presented tachistoscopically to paranoid and nonparanoid schizophrenics, nonschizophrenic psychiatry controls, and normal subjects. Types of information-processing used by paranoid and nonparanoid schizophrenics were also examined. All groups identified letters with greater accuracy with left hemisphere presentation. Group differences in the letter task disappeared once education was controlled. No hemisphere effect was found for dot enumeration but group differences emerged. As predicted, paranoids and controls processed the dots serially and hence decreased in accuracy over frame size. Nonparanoids processed in an automatic mode, revealing the same degree of accuracy over all dot sizes. The poorer performance of the nonparanoids in dot enumeration is discussed in terms of the task requiring bilateral processing and the nonparanoids' failure to integrate the processing of left and right hemispheres.     

Autonomic responses of paranoid, nonparanoid schizophrenic, and normal subjects to affective visual stimulation.

This investigation utilized a procedure designed to determine patterns of cognitive appraisal, and autonomic reactivity which characterize groups of normals, and paranoid and nonparanoid schizophrenics. Results indicated that both groups of schizophrenics evidenced electrodermal habituation and increased finger pulse constriction. Normals indicated that stress stimuli became less disturbing over trials and displayed both electrodermal and digital vasomotor habituation. Electrodermal habituation curves for paranoids and normals were similar, with nonparanoids evidencing slower habituation. Paranoids tended to under-rate or deny their emotional reactions.     

Neural bases of different cognitive strategies for facial affect processing in schizophrenia

OBJECTIVE: To examine the neural basis and dynamics of facial affect processing in schizophrenic patients as compared to healthy controls. METHOD: Fourteen schizophrenic patients and fourteen matched controls performed a facial affect identification task during fMRI acquisition. The emotional task included an intuitive emotional condition (matching emotional faces) and a more cognitively demanding condition (labeling emotional faces). Individual analysis for each emotional condition, and second-level t-tests examining both within-, and between-group differences, were carried out using a random effects approach. Psychophysiological interactions (PPI) were tested for variations in functional connectivity between amygdala and other brain regions as a function of changes in experimental conditions (labeling versus matching). RESULTS: During the labeling condition, both groups engaged similar networks. During the matching condition, schizophrenics failed to activate regions of the limbic system implicated in the automatic processing of emotions. PPI revealed an inverse functional connectivity between prefrontal regions and the left amygdala in healthy volunteers but there was no such change in patients. Furthermore, during the matching condition, and compared to controls, patients showed decreased activation of regions involved in holistic face processing (fusiform gyrus) and increased activation of regions associated with feature analysis (inferior parietal cortex, left middle temporal lobe, right precuneus). CONCLUSIONS: Our findings suggest that schizophrenic patients invariably adopt a cognitive approach when identifying facial affect. The distributed neocortical network observed during the intuitive condition indicates that patients may resort to feature-based, rather than configuration-based, processing and may constitute a compensatory strategy for limbic dysfunction.     

Dysphoric response to neuroleptic treatment in schizophrenia: its relationship to autonomic arousal and prognosis.

Longitudinal pharmacotherapeutic data from 58 schizophrenic patients suggest that the emergence of a dysphoric state, characterized by a combination of anxiety, depression, and accusatoriness, early in the course of neuroleptic treatment augurs poor therapeutic outcome and is associated with an unfavorable prognostic classification and a tendency for autonomic arousal to increase with treatment from a drug-free base line somewhat higher than normal. These associations particularly characterized the nonparanoid schizophrenics with nuclear prognostic classification and poor short-term as well as long-term therapeutic outcome; they did not apply to the paranoids. The dysphoric response was unrelated to base-line dysphoria or to the extrapyramidal reactions to neuroleptic medication, and seemed to reflect some basic biological differences between the poor prognosis nonparanoid, the good prognosis nonparanoid, and the paranoid schizophrenics.     

Cognitive concomitants of hemispheric dysfunction in schizophrenia.

Forty-eight schizophrenics (24 paranoids, 24 nonparanoids) and 24 matched controls (12 men and 12 women in each group) were asked to detect the differences between 30 pairs of altered pictures presented successively (15 pairs) and simultaneously (15 pairs) in a counterbalanced order. Overall performance, as measured by reaction time and response quality, was better for controls than for schizophrenics. However, schizophrenics, like right hemisphere brain-damaged patients who presumably rely on their left hemisphere, reacted faster in the successive presentation procedure while the controls reacted equally fast in both conditions. These results support the hypothesis that schizophrenics tend to overactivate their left dysfunctional hemisphere. Twenty-four depressed patients, tested in the same procedure, showed a pattern of results similar to that of controls, suggesting that the results obtained for schizophrenics are not a general characteristic of psychosis.     

Differential effect of prior event information on reaction time with respect to paranoid vs nonparanoid symptomatology.

The effect on reaction time, of prior information concerning the imperative stimulus, was investigated with respect to the dimension of paranoid vs nonparanoid symptomatology of schizophrenia. In the first experiment, the auditory warning signal was followed by the imperative stimulus, which was a straight line, a triangle or a rectangle. Prior information was provided by means of correlation between pitch of the warning signal and shape of the imperative stimulus. The task was to depress the telegraph key promptly at the onset of the imperative stimulus. Twenty chronic undifferentiated schizophrenics, 20 paranoid schizophrenics and 20 alcoholics participated in the experiment. Reaction time of the chronic undifferentiated schizophrenics increased, and reaction time of the paranoid schizophrenics decreased, when the prior event information was provided. In the second experiment, the imperative stimulus consisted of not only different shapes but also different colors. Reaction times of 20 chronic undifferentiated and 20 paranoid schizophrenics were again affected in opposite directions by prior information. In the third experiment, the imperative stimulus was either 1, 3 or 5 dark dots. Twenty each of the chronic undifferentiated and paranoid schizophrenics participated in the experiment. The opposite effects of prior information on reaction time with respect to the dimension of paranoid vs nonparanoid symptomatology, were again demonstrated. It was concluded that paranoid vs nonparanoid symptomatology is based on two elementary processes which are dichotomous and characteristically different from each other.     

Emotion recognition in Chinese people with schizophrenia

This study examined whether people with paranoid or nonparanoid schizophrenia would show emotion-recognition deficits, both facial and prosodic. Furthermore, this study examined the neuropsychological predictors of emotion-recognition ability in people with schizophrenia. Participants comprised 86 people, of whom: 43 were people diagnosed with schizophrenia and 43 were controls. The 43 clinical participants were placed in either the paranoid group (n=19) or the nonparanoid group (n=24). Each participant was administered the Facial Emotion Recognition task and the Prosodic Recognition task, together with other neuropsychological measures of attention and visual perception. People suffering from nonparanoid schizophrenia were found to have deficits in both facial and prosodic emotion recognition, after correction for the differences in the intelligence and depression scores between the two groups. Furthermore, spatial perception was observed to be the best predictor of facial emotion identification in individuals with nonparanoid schizophrenia, whereas attentional processing control predicted both prosodic emotion identification and discrimination in nonparanoid schizophrenia patients. Our findings suggest that patients with schizophrenia in remission may still suffer from impairment of certain aspects of emotion recognition.     

Size estimation in paranoid and nonparanoid schizophrenics

Fifteen paranoid and 15 nonparanoid schizophrenics and 15 normal controls were administered a size estimation task which featured two administrations of nonthematic standard stimuli. The standard stimuli were presented under three conditions of background stimuli: a) surrounded by four smaller stimuli of the same kind; b) surrounded by four larger stimuli of the same kind; c) presented without background stimuli. Standard stimuli were presented at exposure times of 33 and 4000 milliseconds. On the first administration, nonparanoid schizophrenics were found to overestimate size relative to paranoidschizophrenics with normal controls intermediate in performance between the paranoid schizophrenics and nonparanoid schizophrenics, particularly on longer stimulus exposure times. The groups did not differ on the second administration. This replication of the results of earlier investigations suggest that the repeated administration of size estimation procedures in which the effects of sequence and thematic content stimuli were inextricably confounded may have contributed to recent conflicting findings in the size estimation literature. Contrary to predictions generated by Cromwell's stimulus redundancy formation, the paranoid schizophrenics were not more affected by the size of the background stimuli than the nonparanoid schizophrenics.     

Dysregulation of arousal and amygdala-prefrontal systems in paranoid schizophrenia

OBJECTIVE: The authors investigated impaired differentiation of limbic-prefrontal systems by autonomic arousal in schizophrenia. It was predicted that paranoid patients would be distinguished by a disjunction of hyperarousal but reduced amygdala and medial prefrontal activity relative to both healthy comparison subjects and patients with nonparanoid schizophrenia. METHOD: Pictures depicting facial expressions of fear were presented to 27 schizophrenia patients (13 paranoid, 14 nonparanoid) and 22 matched healthy comparison subjects in an implicit perception task to evoke limbic activity. Simultaneous functional magnetic resonance imaging and skin conductance arousal recordings were acquired during presentation of faces expressing fear or neutral emotion. Responses to fear stimuli were further examined by contrasting those that were associated with a skin conductance response ("with arousal") and those that were not ("without arousal"). RESULTS: In the comparison subjects, arousal dissociated amygdala/medial prefrontal ("visceral") networks and hippocampus/lateral prefrontal ("context") networks for fear perception. Excessive arousal responses were elicited in the schizophrenia subjects, but there was an associated reduction in amygdala/medial prefrontal activity. This disjunction was pronounced in paranoid patients relative to both healthy subjects and nonparanoid patients. Paranoid patients also showed a relatively greater prefrontal deficit for "without-arousal" responses. CONCLUSIONS: This is the first study to reveal a functional disconnection in autonomic and central systems for processing threat-related signals in patients with paranoid schizophrenia. Paranoid cognition may reflect an internally generated cycle of misattribution regarding incoming fear signals due to a breakdown in the regulation of these systems.     

Dysfunctions of space perception and spatial ability in schizophrenia (author's transl)]

Thirty-seven acute schizophrenics and 25 normal subjects were investigated with regard to their spatial perception, representation, and their spatial ability, Schizophrenics showed significantly poorer performances (in terms of quantity) in those variables, which characterized the ocular apprehension of structures and wholes, the relation of parts to a whole, or the analysis of a whole in its various components as well as the availability of visual engrams, partly in the sense of spatial representation, and the practical realization of imagined spatial configurations. On the other hand, in ocular apprehension, interpretation, and when necessary the practical realization of two-dimensional represented spatial symbols and configurations and perspective abilities there was only statistical trend for quantitatively poorer performances in schizophrenics compared with healthy persons. Factor analysis of the intercorrelation matrices for 14 variables separated out the same 4 factors in each group for space perception and spatial ability. In spite of the demonstrated "quantitative" differences for the single variables between the two groups a marked similarity in a "qualitative" sense was found, when the two-factor structures were compared mathematically (similarity coefficient: 0.664). In order to specify these differences, 56 schizophrenics were classified as paranoid or nonparanoid and investigated in the above-mentioned manner. While these groups did not show any significant quantitative difference concerning their performances at variable level, they showed entirely different structures using factor analysis. Spatial perception of the paranoid schizophrenics seemed less structured and their perceptual conception less systematical. On the other hand, when factor structures from nonparanoids and healthy controls were compared mathematically, both groups showed a marked similarity (0.783). An attempt was made to relate these results to other findings of literature and to theories of cognitive and perceptual dysfunctions of schizophrenics.     

Assessing disturbed thinking and cognition using the Ego Impairment Index in older schizophrenia patients: paranoid vs. nonparanoid distinction.

OBJECTIVE: We compared thought-disturbance via the Rorschach-derived Ego Impairment Index (EII) between DSM-IV paranoid vs. nonparanoid (undifferentiated and disorganized) subtypes of older schizophrenia patients. METHODS: 44 DSM-IV medically stable outpatients with schizophrenia (27 paranoid, 17 nonparanoid) and 45 normal comparison participants aged 45-100 years were assessed using the EII, a Rorschach-derived cognitive-based measure of disturbed thinking. Group differences on the EII and the relation of this measure to key demographic and clinical variables were examined. RESULTS: Nonparanoid schizophrenia patients demonstrated significantly greater impairment on the EII than their paranoid counterparts. The EII performance of paranoid patients was similar to normal comparison participants. Furthermore, the paranoid patients displayed better premorbid intellectual functioning, less negative symptoms, and better global cognitive performance than nonparanoid patients. Finally, greater impairment on the EII was correlated with poor performance on a global measure of cognitive ability. CONCLUSIONS: The present findings substantiate previous work suggesting that nonparanoid patients have a form of the illness characterized by worse premorbid functioning and greater disturbed thinking and cognition than their paranoid counterparts.     

Impairment of emotional expression recognition in schizophrenia: A Cuban familial association study

It is well established that schizophrenia is associated with difficulties in recognizing facial emotional expressions, but few studies have reported the presence of this deficit among their unaffected relatives. This study attempts to add new evidence of familial association on an emotional expression processing test. The study evaluated the performance of 93 paranoid schizophrenia patients, 110 first-degree relatives of probands from multiplex schizophrenia families, and 109 nonpsychiatric controls on a facial emotional recognition test using a computer morphing technique to present the dynamic expressions. The task entailed the recognition of a set of facial expressions depicting the six basic emotions presented in 21 successive frames of increasing intensity. The findings indicated that schizophrenia patients were consistently impaired for the recognition of the six basic facial expressions. In contrast, their unaffected relatives showed a selective impairment for the recognition of disgust and fearful expressions. Familial association of selective facial emotional expressions processing deficit may further implicate promising new endophenotypes that can advance the understanding of affective deficits in schizophrenia.     

Cerebral asymmetry in subtypes of schizophrenia

CT scans of 26 nonparanoid and 10 paranoid right-handed male schizophrenics were examined. Multiple measurements were made of each region of the brain and a standard error of measurement with a confidence level of p less than .01 was used to define significant asymmetry. Three aspects of cerebral asymmetry, i.e., local hemispheric width, local hemispheric protrusion, and regional hemispheric size, were examined. Paranoid and nonparanoid patients were similar in their patterns of frontal asymmetries. However, a substantial proportion of nonparanoid schizophrenics had wider, longer, and larger right parieto-occipital lobes compared to paranoid patients.     

Facial affect decoding in schizophrenic disorders: a study using event-related potentials

Deficits in emotional processing are evident in schizophrenia, but the underlying processes are still under debate. In this study we tried to replicate findings of diminished prefrontal electroencephalographic response during facial affect recognition in healthy controls and subsequently in schizophrenic patients. As a first step, we analysed the event-related potentials (ERPs) of 36 healthy subjects during emotional expression decoding compared with neutral face viewing. Subsequently, the ERPs of 22 patients with schizophrenia were compared with the ERPs of 22 healthy subjects matched for age and sex. The hypothesised increase in the negative component at 200 ms over frontal brain regions during facial affect decoding was not found in this study. Instead we found increased positive amplitudes at 300 ms over parietal brain areas for the active affect-decoding task compared with the passive neutral face-viewing task. Interestingly, schizophrenic patients had higher amplitudes in the neutral condition than did healthy controls. This effect was more pronounced in the paranoid subgroup of patients.     

Looking differences in relation to examiner's attitude in paranoid patients and normal controls

The differences in amount and pattern of looking during interviews of 20 male paranoid patients and 20 nomral controls are investigated in relation to a female examiner's change of attitude, as indicated by change in the tone of her voice, by means of a cross-over design. The results indicate that paranoids do not follow the "decreased looking" model suggested for schizophrenics in other studies. Patients show a significant order effect, a higher overall amount of looking and a quite opposite pattern of looking across interviews as compared to controls. It is suggested that patients may have difficulties in regulating their visual behaviour according to examiner's attitude, resulting to a "stereotyped" pattern of looking. These findings are discussed with particular reference to visual information processing.     

Exploring the nature of facial affect processing deficits in schizophrenia

Schizophrenia has been associated with deficits in facial affect processing, especially negative emotions. However, the exact nature of the deficit remains unclear. The aim of the present study was to investigate whether schizophrenia patients have problems in automatic allocation of attention as well as in controlled evaluation of facial affect. Thirty-seven patients with schizophrenia were compared with 41 control subjects on incidental facial affect processing (gender decision of faces with a fearful, angry, happy, disgusted, and neutral expression) and degraded facial affect labeling (labeling of fearful, angry, happy, and neutral faces). The groups were matched on estimates of verbal and performance intelligence (National Adult Reading Test; Raven's Matrices), general face recognition ability (Benton Face Recognition), and other demographic variables. The results showed that patients with schizophrenia as well as control subjects demonstrate the normal threat-related interference during incidental facial affect processing. Conversely, on controlled evaluation patients were specifically worse in the labeling of fearful faces. In particular, patients with high levels of negative symptoms may be characterized by deficits in labeling fear. We suggest that patients with schizophrenia show no evidence of deficits in the automatic allocation of attention resources to fearful (threat-indicating) faces, but have a deficit in the controlled processing of facial emotions that may be specific for fearful faces.     

Differential impairments of facial affect recognition in schizophrenia subtypes and major depression

The goal of this study was to assess facial affect recognition abilities in subjects with various schizophrenia subtypes and subjects with major depression. A total of six disorganized, 21 paranoid and 18 residual subjects with schizophrenia (DSM-IV criteria) were compared with 21 subjects with major depression (DSM-IV criteria) and 30 matched healthy control subjects. Two experimental tasks requiring the sorting and rating of emotional facial expressions were applied. Disorganized and paranoid subjects showed strong impairments in the sorting of emotional facial expressions. Depressive subjects displayed only minor deficits, and residual subjects were unimpaired. Subjects with disorganized schizophrenia rated emotional facial expressions as more aroused, and depressive subjects rated them as less aroused, than the other study groups. Our study demonstrates strong deficits in facial affect recognition in subjects with schizophrenia and pronounced disorganized or psychotic symptoms. Deficits in facial affect recognition are specific to schizophrenia. They may be considered as a state marker of schizophrenia.     

Functional MRI of facial emotion recognition deficits in schizophrenia and their electrophysiological correlates

Empirical evidence suggests impaired facial emotion recognition in schizophrenia. However, the nature of this deficit is the subject of ongoing research. The current study tested the hypothesis that a generalized deficit at an early stage of face-specific processing (i.e. putatively subserved by the fusiform gyrus) accounts for impaired facial emotion recognition in schizophrenia as opposed to the Negative Emotion-specific Deficit Model, which suggests impaired facial information processing at subsequent stages. Event-related potentials (ERPs) were recorded from 11 schizophrenia patients and 15 matched controls while performing a gender discrimination and a facial emotion recognition task. Significant reduction of the face-specific vertex positive potential (VPP) at a peak latency of 165 ms was confirmed in schizophrenia subjects whereas their early visual processing, as indexed by P1, was found to be intact. Attenuated VPP was found to correlate with subsequent P3 amplitude reduction and to predict accuracy when performing a facial emotion discrimination task. A subset of ten schizophrenia patients and ten matched healthy control subjects also performed similar tasks in the magnetic resonance imaging scanner. Patients showed reduced blood oxygenation level-dependent (BOLD) activation in the fusiform, inferior frontal, middle temporal and middle occipital gyrus as well as in the amygdala. Correlation analyses revealed that VPP and the subsequent P 3a ERP components predict fusiform gyrus BOLD activation. These results suggest that problems in facial affect recognition in schizophrenia may represent flow-on effects of a generalized deficit in early visual processing.     

Impaired emotional facial expression recognition in alcoholics: are these deficits specific to emotional cues?

Previous studies have repeatedly linked alcoholism is to impairment in emotional facial expression decoding. The present study aimed at extending previous findings while controlling for exposure times of stimuli. Further, a control task was added on the decoding of non-emotional facial features. Twenty-five alcoholic participants were compared to 26 control participants matched for age, sex and educational level. Participants performed two computer tasks consisting of presentation of photographs of faces for either 250 or 1000 ms. The first task required "yes" or "no" responses as rapidly as possible to questions regarding non-emotional features of the face (gender, age range and cultural identity). The second task involved a different set of photographs implicating emotional facial expression decoding, with the same exposure times. Again, rapid "yes" or "no" responses to trials combining 32 emotional facial expressions by eight emotional labels (happiness, sadness, fear, anger, disgust, surprise, shame, and contempt) were required from participants. Reaction times were recorded for both tasks. Alcoholic and control participants showed similar results in both tasks in terms of response accuracy. Yet, in the emotional facial expression task, alcoholic participants' responses matched more negative emotional labels, especially sadness. Further, alcoholics were slower than control participants specifically to answer emotional questions on emotional facial expression. No differences appeared on reaction times in the control task. Contrary to expectations, no interaction of stimulus time exposure and group was observed. Overall, these findings replicate and extend previous results on emotional facial expression decoding ability: Alcoholics are specifically impaired on emotional non-verbal behavior information processing: They are slower to correctly identify an emotion.     

Effects of emotion and identity on facial affect processing in schizophrenia

We used facial affect labeling and matching tasks to study effects of (1) emotion and (2) identity on facial affect processing in patients with remitted schizophrenia (n=30) compared with healthy controls (n=30). The patients (1) had a specific deficit for labeling facial affects of sadness and anger but not happiness, disgust and fear; they (2) performed as well as controls in matching facial affects in one face but were impaired in matching facial affects in two different faces. The patients' impairment in facial affect processing may be emotion-specific. The effects of identity on facial affect processing are discussed in the light of several hypotheses (a deficit of context processing, a global-local processing impairment or a selective attention deficit), and may be related to frontal, prefrontal or amygdala dysfunctions.