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Orbitofrontal cortex functioning in schizotypy: Relationship between SPQ ratings and punishment learning
11. Psychology, Neuro-
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this disposition relates to other symptoms of psychosis and related abnormalities associated with schizophrenia. In this study we compared hallucination-prone individuals with control subjects without this disposition on the Schizotypal Personality Questionnaire and an Alexithymia Questionnaire. Based on the Launey-Slade Hallucination Scale (LSHS) scores of 200 university students, forty participants were selected: High (n=20) and low (n=20) scoring subjects. There were no significant differences on age and gender between the high and low LSHS groups. The dimensions positive schizotypy and disorganization of the Schizotypal Personality Questionnaire showed significant differences for the two LSHS groups. This suggests that people with a certain proneness to hallucinations may also show other psychotic-like symptoms. On the Alexithymia Questionnaire the subscales fantasizing and emotionalizing differed significantly for the two groups. However, the hallucination-prone group had lower overall alexithymia-scores than controls in the present study. Although schizophrenia has been associated with a higher incidence of alexithymia in previous studies, this association was mainly limited to negative symptoms. We therefore suggest that positive symptoms may be associated with increased emotionality, which is consistent with recent research on amygdala function in schizophrenia.
A MOTOR THEORY OF THE ORIGIN OF SCHIZOPHRENIA J. van Hoof Research, GGZ Oost Brabant, Oss, Noord Brabant, Netherlands The core problem in schizophrenia research is the lack of an adequate pathophysiological model. An attempt was made to bridge this gap between etiological factors and clinical symptomatology (van Hoof, 2002). In this model, it is assumed that schizophrenia is the manifestation of an imbalance between two mechanisms in the brain: the first is motor power or drive and the second is steering or guidance. Both mechanisms are used to control movements. The core of this model's thesis is that during the phylo- and ontogenesis of the human brain both of these mechanisms are implemented in a repetitive way from the "how to do" motor domain into the "what to do" intentional (limbic) domain through cortical- subcortical circuits. The first, striatal mechanism (parallel information processing) is necessary to initiate and calibrate movements and intentions, such as intimidation or affiliation. This intentional drive mechanism is organized primarily by a circuit located in the ventral part of the brain. The second, cerebellar (serial information processing) mechanism is necessary for guidance. The intentional variant of the representational guidance mechanism is organized primarily in a circuit located in the dorsal part of the brain. The application of both mechanisms during brain development allow the creation of unique human capacities; viz. the ability to create (meta) representations, language and consciousness, but also an increased capacity to deal with conflicting demands and emotions. Evidence is accumulating that the principally genetically based reliance on one or both types of mechanisms has a bimodal distribution. A genetically based insufficient development of the drive mechanism and an exaggerated reliance on the vulnerable representational guidance mechanism will cause an imbalance. The repetitive implementation of these mechanisms will increase this imbalance and create a situation where comparatively small stressors produce a tipping of the scale manifesting itself as schizophrenia. This model has a greater explanatory power than current alternatives and therefore it will provide a useful framework for further research. Reference: Van Hoof J.J.M., 2002.The Abnormal Development of Drive and Guidance Mechanisms in the Brain: The Pathogenesis of Schizophrenia. Acta Neuropsychiatrica: 14:134-146.
ORBITOFRONTAL CORTEX F U N C T I O N I N G IN SCHIZOTYPY: RELATIONSHIP B E T W E E N SPQ RATINGS AND PUNISHMENT LEARNING S. van Rijn,* J. van Honk, A. Aleman, M. van 't Wout, R. S. Kahn Psychonomics, Helmhohz Institute, Utrecht, Netherlands There is a considerable amount of evidence that the orbitofrontal cortex (OFC) forms part of a circuit underlying emotional information processing. More specifically, it is involved in punishment learning. In patients suffering from schizophrenia, abnormalities of the OFC have been shown on a neuropathological as well as a structural and functional neuro-imaging level. In their daily lives, they often encounter the consequences of poor personal and social judgements and have difficulties in social interactions. Recently, such social dysfnnction, considered as a wominent premorbid feature of the illness, has been related to abnormal OFC-morphology. The aim of our study was to examine the relationship between OFC functioning (i.e. punishment learning) and schizotypical traits. We made use of the Iowa Gambling Task (GT), in which subjects are instructed to maximalize money gain by selecting cards from advantageous and disadvantageous decks. Decisions should become motivated by reward and punishment-schedules inherent in the task. Lesion and neuro-imaging studies have shown performance on this task to depend on orbitofrontal cortex functioning. Forty university students completed the SPQ and performed the GT. Of the SPQ dimensions of negative schizotypy, the subscale 'no close friends' correlated significantly with reduced punishment learning (r=0.39, p=0.014). All other correlations were not significant (p>0.10). These findings provide evidence for a link between a dimension of schizotypy, i.e. 'no close friends', and orbitofrontal dysfunction, more specifically, punishment learning. Future research with clinical populations and using functional neuro-imaging is needed to corroborate and extend these results.
DISCRIMINATION OF FACIAL EXPRESSIONS IN VIOLENT AND NON-VIOLENT PATIENTS W I T H SCHIZOPHRENIA E. M. Weiss,* K. A. Nolan, J. Volavka, J. L o u g h e a d , R. E. Gur, R. C. Gur, C. Kohler Psychiatric Research, Nathan S Kline Institute, Orangeburg, NY, USA Social psychological research underscores the relation between aggression and emotion. Normal individuals are able to voluntarily regulate their negative affect and can also profit from restraint-producing cues in their environment, such as facial and vocal signs of anger and fear, that also serve a regulatory role. Epidemiological studies have shown that individuals diagnosed with major mental disorders like schizophrenia are more likely to have engaged in violent behavior than members of the same communities who have nev er been diagnosed with a mental disorder. In this ongoing study we want to examine whether violent and non-violent patients with schizophrenia differ in their ability to discriminate facial emotional expressions (happy, sad, anger, fear, neutral). So far 7 violent and 7 non-violent patients with schizophrenia matched for age and education were evaluated. Violent schizophrenic patients did not have greater difficulty with emotional labeling compared to non-violent patients with schizophrenia but showed a different pattern of mislabeling.
International Congress on Schizophrenia Research 2003
161
this disposition relates to other symptoms of psychosis and related abnormalities associated with schizophrenia. In this study we compared hallucination-prone individuals with control subjects without this disposition on the Schizotypal Personality Questionnaire and an Alexithymia Questionnaire. Based on the Launey-Slade Hallucination Scale (LSHS) scores of 200 university students, forty participants were selected: High (n=20) and low (n=20) scoring subjects. There were no significant differences on age and gender between the high and low LSHS groups. The dimensions positive schizotypy and disorganization of the Schizotypal Personality Questionnaire showed significant differences for the two LSHS groups. This suggests that people with a certain proneness to hallucinations may also show other psychotic-like symptoms. On the Alexithymia Questionnaire the subscales fantasizing and emotionalizing differed significantly for the two groups. However, the hallucination-prone group had lower overall alexithymia-scores than controls in the present study. Although schizophrenia has been associated with a higher incidence of alexithymia in previous studies, this association was mainly limited to negative symptoms. We therefore suggest that positive symptoms may be associated with increased emotionality, which is consistent with recent research on amygdala function in schizophrenia.
A MOTOR THEORY OF THE ORIGIN OF SCHIZOPHRENIA J. van Hoof Research, GGZ Oost Brabant, Oss, Noord Brabant, Netherlands The core problem in schizophrenia research is the lack of an adequate pathophysiological model. An attempt was made to bridge this gap between etiological factors and clinical symptomatology (van Hoof, 2002). In this model, it is assumed that schizophrenia is the manifestation of an imbalance between two mechanisms in the brain: the first is motor power or drive and the second is steering or guidance. Both mechanisms are used to control movements. The core of this model's thesis is that during the phylo- and ontogenesis of the human brain both of these mechanisms are implemented in a repetitive way from the "how to do" motor domain into the "what to do" intentional (limbic) domain through cortical- subcortical circuits. The first, striatal mechanism (parallel information processing) is necessary to initiate and calibrate movements and intentions, such as intimidation or affiliation. This intentional drive mechanism is organized primarily by a circuit located in the ventral part of the brain. The second, cerebellar (serial information processing) mechanism is necessary for guidance. The intentional variant of the representational guidance mechanism is organized primarily in a circuit located in the dorsal part of the brain. The application of both mechanisms during brain development allow the creation of unique human capacities; viz. the ability to create (meta) representations, language and consciousness, but also an increased capacity to deal with conflicting demands and emotions. Evidence is accumulating that the principally genetically based reliance on one or both types of mechanisms has a bimodal distribution. A genetically based insufficient development of the drive mechanism and an exaggerated reliance on the vulnerable representational guidance mechanism will cause an imbalance. The repetitive implementation of these mechanisms will increase this imbalance and create a situation where comparatively small stressors produce a tipping of the scale manifesting itself as schizophrenia. This model has a greater explanatory power than current alternatives and therefore it will provide a useful framework for further research. Reference: Van Hoof J.J.M., 2002.The Abnormal Development of Drive and Guidance Mechanisms in the Brain: The Pathogenesis of Schizophrenia. Acta Neuropsychiatrica: 14:134-146.
ORBITOFRONTAL CORTEX F U N C T I O N I N G IN SCHIZOTYPY: RELATIONSHIP B E T W E E N SPQ RATINGS AND PUNISHMENT LEARNING S. van Rijn,* J. van Honk, A. Aleman, M. van 't Wout, R. S. Kahn Psychonomics, Helmhohz Institute, Utrecht, Netherlands There is a considerable amount of evidence that the orbitofrontal cortex (OFC) forms part of a circuit underlying emotional information processing. More specifically, it is involved in punishment learning. In patients suffering from schizophrenia, abnormalities of the OFC have been shown on a neuropathological as well as a structural and functional neuro-imaging level. In their daily lives, they often encounter the consequences of poor personal and social judgements and have difficulties in social interactions. Recently, such social dysfnnction, considered as a wominent premorbid feature of the illness, has been related to abnormal OFC-morphology. The aim of our study was to examine the relationship between OFC functioning (i.e. punishment learning) and schizotypical traits. We made use of the Iowa Gambling Task (GT), in which subjects are instructed to maximalize money gain by selecting cards from advantageous and disadvantageous decks. Decisions should become motivated by reward and punishment-schedules inherent in the task. Lesion and neuro-imaging studies have shown performance on this task to depend on orbitofrontal cortex functioning. Forty university students completed the SPQ and performed the GT. Of the SPQ dimensions of negative schizotypy, the subscale 'no close friends' correlated significantly with reduced punishment learning (r=0.39, p=0.014). All other correlations were not significant (p>0.10). These findings provide evidence for a link between a dimension of schizotypy, i.e. 'no close friends', and orbitofrontal dysfunction, more specifically, punishment learning. Future research with clinical populations and using functional neuro-imaging is needed to corroborate and extend these results.
DISCRIMINATION OF FACIAL EXPRESSIONS IN VIOLENT AND NON-VIOLENT PATIENTS W I T H SCHIZOPHRENIA E. M. Weiss,* K. A. Nolan, J. Volavka, J. L o u g h e a d , R. E. Gur, R. C. Gur, C. Kohler Psychiatric Research, Nathan S Kline Institute, Orangeburg, NY, USA Social psychological research underscores the relation between aggression and emotion. Normal individuals are able to voluntarily regulate their negative affect and can also profit from restraint-producing cues in their environment, such as facial and vocal signs of anger and fear, that also serve a regulatory role. Epidemiological studies have shown that individuals diagnosed with major mental disorders like schizophrenia are more likely to have engaged in violent behavior than members of the same communities who have nev er been diagnosed with a mental disorder. In this ongoing study we want to examine whether violent and non-violent patients with schizophrenia differ in their ability to discriminate facial emotional expressions (happy, sad, anger, fear, neutral). So far 7 violent and 7 non-violent patients with schizophrenia matched for age and education were evaluated. Violent schizophrenic patients did not have greater difficulty with emotional labeling compared to non-violent patients with schizophrenia but showed a different pattern of mislabeling.
International Congress on Schizophrenia Research 2003