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Correlations between RCBF and behavior in drug-free schizophrenic patients
14. Neuroimaging, Functional
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social reasoning task. We used the same task to compare the brain activation of DSM-IV schizophrenic patients (n = 8, mean age 29 years, 8 males) and that of healthy controls (n = 12, mean age 29 years, 9 males and 3 females) in making empathic judgements. Functional data were acquired using a 1.5 T Eclipse system (Marconi Medical Systems, Ohio) at the University of Sheffield, and were analyzed using statistical parametric mapping (SPM). The randomeffects analysis with sex as a covariate (p < 0.001, uncorrected for multiple comparisons, extent threshold less than 5 voxels) showed significantly less BOLD signal in patients with schizophrenia than in the control group in the superior frontal gyms (BA 10; - 10 63 24; 11 voxels), in the medial frontal gyrus (BA 6; -8, -20, 58; 5 voxels), in the middle frontal gyms (BA 8; -38, 24, 47; 9 voxels), in the inferior temporal gyrus/fusiform gyms (BA 21; -57, -7, -23; 15 voxels), and in the precuneus (BA 31; -10, -71, 24; 16 voxels). The findings overall support functional neuroimaging studies implicating left middle and medial frontal gyms underactivation in patients with schizophrenia during Theory of Mind (TOM) type tasks. More importantly, the results emphasize the role of the temporal cortex in empathy and support the idea that underactivation of the temporal cortex in patients with schizophrenia may underlie the neural foundation of dysempathy as part of the social cognitive deficits associated with this disorder.
CORRELATIONS BETWEEN RCBF AND BEHAVIOR IN DRUG-FREE SCHIZOPHRENIC PATIENTS S. M. Lee,* M. Weiler, H. Holcomb, C. Tamminga, A. L a h 6
Psychiatry, Maryland Psychiatric Research Center, Baltimore, MD, USA Over the past several years, we have withdrawn schizophrenic patients from all psychotropic medications for various lengths of time in preparation for PET imaging studies. In this study, we evaluated what area in the brain rCBF patterns correlated with psychotic symptoms during the time of the unmedicated PET scan. Based on our previous studies, we had hypothesized that such correlation would be found in the anterior cingulate cortex (ACC). Because it is often argued that a short medication withdrawal period may not be sufficient to reset normal activity in the basal ganglia, we sought to determine the effect of the length of medication withdrawal on that region's rCBF patterns. A total of 33 patients were scanned using PET with 15O, while unmedicated for a period ranging f r om 6 to 90 days. Using SPM analysis and BPRS Total scores as covariates, we evaluated which region's rCBF correlated with symptoms. We assessed the effect of length of withdrawal on rCBF patterns in two ways: (1) by using the number of days of withdrawal as a covariate and (2) by contrasting rCBF patterns of patients withdrawn from medication for a period equal to or lower than 15 days (n=20) to those who were withdrawn for a period longer than 15 days (n=13). As hypothesized, ACC rCBF pattern was significantly and positively correlated with BPRS Total scores (r =0.55). There was no significant correlation between rCBF pattern in the basal ganglia and the number of days of withdrawal. Likewise, we did not find a significant difference in basal ganglia rCBF patterns between patients who were withdrawn for a short period compared to those who were withdrawn for a longer period of time. This study which reveals a correlation between ACC rCBF and psychotic symptoms adds to a body of evidence implicating the ACC in a distributed neural network that mediates psychosis. Our data do not support the contention that a
short medication withdrawal is inadequate to reset a normal rCBF pattern in the basal ganglia.
LACK OF RIGHT HEMISPHERIC ACTIVATION DURING WORD ENCODING IN SCHIZOPHRENIC PATIENTS: AN FMRI STUDY D. T. Leube,* A. Rapp, W. Grodd, M. Bartels, T. Kircher
Psychiatric University Hospital, University of Tuebingen, Tuebingen, Baden- Wuertemberg, Germany Patients with schizophrenia show a deficit in word encoding independent of other cognitive deficits. The neural correlates of this impairment are unknown. In an fMRI study we compared episodic word encoding in schizophrenic patients and healthy controls. We investigated 8 DSM IV diagnosed schizophrenic patients and 8 matched healthy control subjects. They were asked to remember words displayed one by one on a screen, while brain activation was measured with fMRI. We found a stronger activation in the left inferior frontal region (IFG) in: schizophrenic patients and a higher activity in right temporal areas (middle temporal/angular gyms) in the control subjects. Linguistic context is processed in right hemispheric temporal areas. Schizophrenic patients may fail to activate these ressources. This may impair the building of semantic associations, necessary for an efficient encoding process.
RELATION BETWEEN AUDITORY ATTENTIONAL DEFICITS AND NEUROANATOMICAL SYSTEMS IN SCHIZOPHRENIA R Lopez,* N. Ojeda, F. Ortufio, S. C e r v e r a - E n g u i x
D Psychiatry and Medical Psychology, Cl[nica Universitaria de Navarra, Pamplona, Navarra, Spain This study examine the relation between attentional deficits in naive patients with schizophrenia as evidenced through neuropsychological testing and neuroanatomical correlates in both attentionat systems: anterior and posterior. Posner and Petersen (1990) proposed the existence of 2 attentioanl systems; independent systems in their type of processing and their neuroanatomical basis: the anterior and the posterior systems. Attention, specially visual attention, has traditionally reported as deficient in Sz. However, fewer differentiation has been added regarding auditory attention, both anterior (voluntary, controlled) and posterior attention (automatized attention). PET 150-water imaging was taken for 11 naive patients with Schizophrenia and ten controls during automatic, and controlled tasks which required components of auditory attention. Neuropsychological testing included various attentional test: STROOE TMT, BTA, WCST, and Digits (direct and inverse). Data obtained shows that patients performed significantly worse than normal controls in all tests of attention. Exceptionally, they performed equally well during the simple auditory task required during the PET imaging (non statistically significant differences compared with controls). This result had a negative significant con'elation with defficiencies in blod flow activation in regions related to both, anterior and posterior attentional systems; supplementary motor area (SMA), precentral gyrus and dorsolateral prefrontal cortex (DLPFC), and cingulate. Our results: 1. confirm attentional defficiencies in naive patients with Schizophrenia. 2. Those defficits have a significant correlation with neuroanatomical defficiencies in blood flow, specially in the cited regions. 3. Neuroanatomical changes (differences) are shown even
International Congress on Schizophrenia Research 2003
227
social reasoning task. We used the same task to compare the brain activation of DSM-IV schizophrenic patients (n = 8, mean age 29 years, 8 males) and that of healthy controls (n = 12, mean age 29 years, 9 males and 3 females) in making empathic judgements. Functional data were acquired using a 1.5 T Eclipse system (Marconi Medical Systems, Ohio) at the University of Sheffield, and were analyzed using statistical parametric mapping (SPM). The randomeffects analysis with sex as a covariate (p < 0.001, uncorrected for multiple comparisons, extent threshold less than 5 voxels) showed significantly less BOLD signal in patients with schizophrenia than in the control group in the superior frontal gyms (BA 10; - 10 63 24; 11 voxels), in the medial frontal gyrus (BA 6; -8, -20, 58; 5 voxels), in the middle frontal gyms (BA 8; -38, 24, 47; 9 voxels), in the inferior temporal gyrus/fusiform gyms (BA 21; -57, -7, -23; 15 voxels), and in the precuneus (BA 31; -10, -71, 24; 16 voxels). The findings overall support functional neuroimaging studies implicating left middle and medial frontal gyms underactivation in patients with schizophrenia during Theory of Mind (TOM) type tasks. More importantly, the results emphasize the role of the temporal cortex in empathy and support the idea that underactivation of the temporal cortex in patients with schizophrenia may underlie the neural foundation of dysempathy as part of the social cognitive deficits associated with this disorder.
CORRELATIONS BETWEEN RCBF AND BEHAVIOR IN DRUG-FREE SCHIZOPHRENIC PATIENTS S. M. Lee,* M. Weiler, H. Holcomb, C. Tamminga, A. L a h 6
Psychiatry, Maryland Psychiatric Research Center, Baltimore, MD, USA Over the past several years, we have withdrawn schizophrenic patients from all psychotropic medications for various lengths of time in preparation for PET imaging studies. In this study, we evaluated what area in the brain rCBF patterns correlated with psychotic symptoms during the time of the unmedicated PET scan. Based on our previous studies, we had hypothesized that such correlation would be found in the anterior cingulate cortex (ACC). Because it is often argued that a short medication withdrawal period may not be sufficient to reset normal activity in the basal ganglia, we sought to determine the effect of the length of medication withdrawal on that region's rCBF patterns. A total of 33 patients were scanned using PET with 15O, while unmedicated for a period ranging f r om 6 to 90 days. Using SPM analysis and BPRS Total scores as covariates, we evaluated which region's rCBF correlated with symptoms. We assessed the effect of length of withdrawal on rCBF patterns in two ways: (1) by using the number of days of withdrawal as a covariate and (2) by contrasting rCBF patterns of patients withdrawn from medication for a period equal to or lower than 15 days (n=20) to those who were withdrawn for a period longer than 15 days (n=13). As hypothesized, ACC rCBF pattern was significantly and positively correlated with BPRS Total scores (r =0.55). There was no significant correlation between rCBF pattern in the basal ganglia and the number of days of withdrawal. Likewise, we did not find a significant difference in basal ganglia rCBF patterns between patients who were withdrawn for a short period compared to those who were withdrawn for a longer period of time. This study which reveals a correlation between ACC rCBF and psychotic symptoms adds to a body of evidence implicating the ACC in a distributed neural network that mediates psychosis. Our data do not support the contention that a
short medication withdrawal is inadequate to reset a normal rCBF pattern in the basal ganglia.
LACK OF RIGHT HEMISPHERIC ACTIVATION DURING WORD ENCODING IN SCHIZOPHRENIC PATIENTS: AN FMRI STUDY D. T. Leube,* A. Rapp, W. Grodd, M. Bartels, T. Kircher
Psychiatric University Hospital, University of Tuebingen, Tuebingen, Baden- Wuertemberg, Germany Patients with schizophrenia show a deficit in word encoding independent of other cognitive deficits. The neural correlates of this impairment are unknown. In an fMRI study we compared episodic word encoding in schizophrenic patients and healthy controls. We investigated 8 DSM IV diagnosed schizophrenic patients and 8 matched healthy control subjects. They were asked to remember words displayed one by one on a screen, while brain activation was measured with fMRI. We found a stronger activation in the left inferior frontal region (IFG) in: schizophrenic patients and a higher activity in right temporal areas (middle temporal/angular gyms) in the control subjects. Linguistic context is processed in right hemispheric temporal areas. Schizophrenic patients may fail to activate these ressources. This may impair the building of semantic associations, necessary for an efficient encoding process.
RELATION BETWEEN AUDITORY ATTENTIONAL DEFICITS AND NEUROANATOMICAL SYSTEMS IN SCHIZOPHRENIA R Lopez,* N. Ojeda, F. Ortufio, S. C e r v e r a - E n g u i x
D Psychiatry and Medical Psychology, Cl[nica Universitaria de Navarra, Pamplona, Navarra, Spain This study examine the relation between attentional deficits in naive patients with schizophrenia as evidenced through neuropsychological testing and neuroanatomical correlates in both attentionat systems: anterior and posterior. Posner and Petersen (1990) proposed the existence of 2 attentioanl systems; independent systems in their type of processing and their neuroanatomical basis: the anterior and the posterior systems. Attention, specially visual attention, has traditionally reported as deficient in Sz. However, fewer differentiation has been added regarding auditory attention, both anterior (voluntary, controlled) and posterior attention (automatized attention). PET 150-water imaging was taken for 11 naive patients with Schizophrenia and ten controls during automatic, and controlled tasks which required components of auditory attention. Neuropsychological testing included various attentional test: STROOE TMT, BTA, WCST, and Digits (direct and inverse). Data obtained shows that patients performed significantly worse than normal controls in all tests of attention. Exceptionally, they performed equally well during the simple auditory task required during the PET imaging (non statistically significant differences compared with controls). This result had a negative significant con'elation with defficiencies in blod flow activation in regions related to both, anterior and posterior attentional systems; supplementary motor area (SMA), precentral gyrus and dorsolateral prefrontal cortex (DLPFC), and cingulate. Our results: 1. confirm attentional defficiencies in naive patients with Schizophrenia. 2. Those defficits have a significant correlation with neuroanatomical defficiencies in blood flow, specially in the cited regions. 3. Neuroanatomical changes (differences) are shown even
International Congress on Schizophrenia Research 2003