Abnormalities In Schizophrenic Patients Research Articles

Wisconsin Card-Sorting Test performance does not discriminate different patterns of premorbid behavioral abnormalities in schizophrenic patients.

It is well documented that premorbid behavior abnormalities precede the onset of schizophrenia in a large number of patients. The research findings suggest that there are differences in the type and severity of these premorbid dysfunctions. Another research field has shown impairment of preschizophrenic patients in several cognitive domains. The present study reports retrospective childhood and adolescence neurobehavioral assessment in 31 patients with schizophrenia by the Child Behavior Checklist (CBCL) and current Wisconsin Card-Sorting Test (WCST) evaluation in order to investigate whether specific behavioral abnormality (BA) patterns are related to executive function as evaluated by the WCST. Cluster analysis was conducted on the childhood premorbid behavior ratings for the schizophrenic patients and two subgroups emerged: (i) Cluster I with an initial low level of BA that increased over the years; and (ii) Cluster II with a high level of BA that remained relatively stable until early adulthood. Furthermore, Cluster II showed more severe current negative and total symptoms, but the two groups did not differ in WCST performance. Our results show that the patterns and severity of CBCL upon retrospective evaluation are not related to WCST performance, which seems to be a feature inherent to the disease process. Different factors could be responsible for cognitive and behavioral disturbances in schizophrenia.

Fetal hypoxia and structural brain abnormalities in schizophrenic patients, their siblings, and controls.

Cortical gray matter reductions and cerebrospinal fluid (CSF) increases are robust correlates of schizophrenia, but their relationships to obstetric and other etiologic risk factors remain to be established. Structured diagnostic interviews, obstetric hospital records, and magnetic resonance imaging scans of the brain were obtained for 64 schizophrenic or schizoaffective patients (representative of all such probands in a Helsinki, Finland, birth cohort), along with 51 of their nonpsychotic full siblings and 54 demographically similar controls without family histories of psychosis. Fetal hypoxia predicted reduced gray matter and increased CSF bilaterally throughout the cortex in patients (gray matter effect sizes, -0.31 to -0.56; CSF effect sizes, 0.25 to 0.47) and siblings (gray matter effect sizes, 0.33 to 0.47; CSF effect sizes, 0.17 to 0.33), most strongly in the temporal lobe. Effect sizes were 2 to 3 times greater among cases born small for their gestational age. Hypoxia also correlated significantly with ventricular enlargement, but only among patients (effect size, 0.31). In contrast, fetal hypoxia was not related to white matter among patients and siblings, nor to any tissue type in any region among controls. The associations were independent of family membership, overall brain volume, age, sex, substance abuse, and prenatal infection. Fetal hypoxia is associated with greater structural brain abnormalities among schizophrenic patients and their nonschizophrenic siblings than among controls at low genetic risk for schizophrenia. This pattern of results points to a gene-environment interaction account of the disorder's neurodevelopmental pathogenesis.

A retrospective study of clozapine and electroencephalographic abnormalities in schizophrenic patients

This study investigated the incidence and nature of clozapine-associated electroencephalographic (EEG) abnormalities and the relationship between EEG abnormality and clozapine dosage in Korean schizophrenic patients. Fifty schizophrenic patients with normal baseline EEG and with additional EEG record examined during clozapine treatment more than once were included. Thirty-one patients (62%) showed abnormal EEGs after clozapine treatment, and two of them had seizures. The majority of EEG abnormalities presented as nonspecific slow waves (SW). Spikes (or spike and wave complexes; SP) and frontal intermittent rhythmic delta activity (FIRDA) were relatively rarely observed. The probability of EEG abnormality was linearly dependent on the daily dose of clozapine and patient's age. Our results can be summarized as follows: (1) a substantial proportion of Korean patients treated with clozapine develops EEG abnormalities, and its incidence is comparable to the published results in Caucasian patients; (2) EEG abnormalities occurred in a dose-dependent manner; and (3) the occurrence of EEG abnormalities did not necessarily lead to future seizure development, except in a small number of cases.

An MRI study of temporal lobe abnormalities and negative symptoms in chronic schizophrenia

Previous magnetic resonance imaging (MRI) studies have reported various subtle brain abnormalities in schizophrenic patients, including temporal lobe abnormalities, which are of particular interest given the role of this brain region in auditory and language processing, and the characteristic deficits in these processes in schizophrenia . Subjects in this study were 16 male patients diagnosed with chronic schizophrenia and 15 healthy male comparison subjects. These patients were characterized by negative symptoms. High spatial resolution coronal MRI 1.5-mm-thick slices were used to measure the gray matter volume of the superior temporal gyrus, anterior and posterior amygdala/hippocampal complex, and parahippocampal gyrus. Patients, relative to normal comparison subjects, evinced a reduction of gray matter volume in bilateral superior temporal gyri and anterior amygdala/hippocampal complex. The reduction in gray matter of the superior temporal gyrus in patients with schizophrenia is consistent with previous findings, and is noteworthy in that it was found in this group of patients with predominantly negative symptoms. The reduction in the anterior amygdala/hippocampal complex was an additional temporal lobe finding. These results underscore the role of temporal lobe structures in the pathophysiology of schizophrenia.

Cytokine profiles in drug-naive schizophrenic patients

A large body of evidence concerning immunological abnormalities in schizophrenic patients seems to suggest a role of the immune system in the multifactorial pathogenesis of schizophrenia. We investigated the production of various cytokines [interleukin (IL)-2, IL-4, IL-10, interferon (INF)-γ] in drug-free ( n=26) and drug-naive ( n=7) schizophrenic patients and in healthy controls ( n=33). Production of IL-2 and INF-γ was significantly higher (respectively P=0.021 and P=0.001) in patients than in controls. These findings provide further evidence that immunological abnormalities are present in some schizophrenic patients.

Structural MRI abnormalities in schizophrenic patients and their unaffected siblings: voxel-based morphometry

Structural MRI abnormalities in schizophrenic patients and their unaffected siblings: voxel-based morphometry

Thought Disorder in Schizophrenia: A Reappraisal of Older Formulations and an Overview of Some Recent Studies

Introduction. Formal thought disorder, as manifested in disorganised speech, is a cardinal symptom of schizophrenia. Method. In this review we examine several older explanations of thought disorder and consider newer cognitive accounts. Results. Older formulations often were not mechanistic and simply redescribed the phenomenon under study. Direct comparisons of thought-disordered schizophrenic patients and jargon aphasic patients indicated that the groups were not similar, as they differed on a number of language variables, including naming and comprehension. Later attentional models also had limitations. Correlations between thought disorder and ''attentional'' measures were often only moderate and the tests or scales used to assess attention or thought disorder may not have accurately measured these constructs. Recent working memory models have lacked convergent validity in that patients with frontal lobe damage and working memory problems do not exhibit thought disorder and that single word association and priming studies elicit abnormalities in schizophrenic patients, findings at odds with the view that thought disorder is a discourse planning problem. In our own series of studies we found compelling evidence that thought disorder may be related to various impairments in semantic processing. These impairments were especially evident on semantic fluency tasks. In fact it was the latter, rather than working memory or attentional tests, that predicted thought disorder. Moreover, we were able to provide a mechanistic account of thought disorder based on qualitative abnormalities in semantic priming paradigms. Conclusions. Patients with thought disorder displayed lack of priming for highly associated within-category words, suggesting that they could not access them in a timely and semantically relevant manner. The literature also has implications for understanding cognitive architecture. Although vocabulary and naming abilities were relatively normal in schizophrenic patients, cognitive maps of semantic space, as determined by multidimensional scaling analyses, indicated disorganisation among semantic entities. These results imply that the size of the lexicon is dissociable from the organisation of the lexicon. In schizophrenia in particular it appears that the latter, rather than the former, is more perturbed.

An automated morphometric analysis of brain abnormalities in schizophrenic patients with auditory hallucinations

An automated morphometric analysis of brain abnormalities in schizophrenic patients with auditory hallucinations

Wisconsin card-sorting test performance does not discriminate different patterns of premorbid behavioral abnormalities in schizophrenic patients

The Wisconsin card-sorting test (WCST) is a commonly used clinical tool for the detection of frontal lobe dysfunction, specifically executive dysfunction. Patients with lesions outside the frontal lobes sometimes show deficits on the WCST, however, and some researchers have implicated hippocampal dysfunction as the cause of the deficit. But a critical role for the hippocampus seems to be untenable because amnesic patients with bilateral medial temporal lobe (MTL) lesions perform the WCST normally. In the case of epileptic patients, an alternative explanation of the card-sorting impairment is the propagation of abnormal discharges from MTL to frontal lobe structures, causing remote interference with executive circuits.

Neurological abnormalities in schizophrenic patients: a prospective follow-up study 5 years after first admission.

The aim of this study was to examine the temporal stability of neurological abnormalities in first-episode schizophrenic patients, and to clarify the relationships between such abnormalities and psychopathology. A total of 18 schizophrenic patients, 11 non-schizophrenic patients and 10 healthy volunteers were examined neurologically at first admission and 5 years later. A significant increase in the number of neurological abnormalities was seen in schizophrenic patients with genetic predisposition and in patients with a non-remitting course of disease. Birth complications had an impact on the occurrence of neurological abnormalities at first admission. The association between a deteriorating course of disease and neurological impairment supports the theory that any possible impairment of the brain in schizophrenia is aggravated during the first 5 years of disease.

Increased levels of CD8+ and CD4 + 45RA + lymphocytes in schizophrenic patients

Peripheral blood (PB) lymphocyte subpopulations, IgG, IgM, IgA and IgE serum immunoglobulins and C3 and C4 complement fractions were evaluated in 29 schizophrenic patients, 31 of their relatives and 20 healthy subjects. The patients fulfilled DSM-III criteria for schizophrenia, and were unmedicated for 3 months prior to the PB sample collection. When compared to healthy controls and their own relatives, the schizophrenic patients showed a lower level of CD4+ cells, while the CD4+45RA+ (naive) subset was significantly higher. Conversely, the number of CD4+45RA-(memory) lymphocytes was significantly lower in schizophrenic patients in comparison to their relatives and controls, while the CD8+ supressor/cytotoxic T-cell percentage was significantly higher. No significant differences were observed for the IgG, IgM, IgA, IgE and C3 and C4 complement fraction levels among the three groups. The present data confirm the presence of immunological abnormalities in schizophrenic patients and suggest a possible role of environmental factors in the triggering of an autoimmune pathogenic mechanism.

Neurological abnormalities in schizophrenic patients and their siblings.

The aim of this study was to investigate the prevalence and type of neurological abnormalities in schizophrenic patients and their nonpsychotic siblings. A comprehensive neurological assessment, including evaluation of both hard and soft signs, was performed for 60 schizophrenic patients, 21 siblings, and 75 normal comparison subjects. None of the comparison subjects scored higher than 6 on the neurological assessment scale, but a score of 7 or higher was given to 67% of patients and 19% of siblings. Both patients and siblings scored significantly higher than comparison subjects on total neurological abnormalities, hard signs, soft signs, primitive reflexes, integrative sensory functions, and motor functions. The most conspicuous abnormalities were motor coordination problems and involuntary movements in the patients and cranial nerve deviations and mirror movements in their siblings. Levels of neurological abnormality were positively correlated within patient-sibling pairs. The total battery and hard signs best discriminated patients from comparison subjects. High levels of neurological abnormality characterize both schizophrenic patients and their siblings. The constellation of abnormalities and absence of overt psychopathology in siblings may represent the mildest form of disturbance within the schizophrenia spectrum. Levels of neurological abnormality covary positively in patients and siblings within the same family, suggesting common genetic and/or environmental pathogenic factors. An extended assessment battery provides optimal discrimination of patients from normal subjects, and hard signs are more differentially associated with schizophrenia than are soft signs. The neurological abnormality has no consistent localizing profile, and nearly all functional domains are involved.

14-129 - EEG abnormalities in schizophrenic patients who treated with clozapine

14-129 - EEG abnormalities in schizophrenic patients who treated with clozapine

Saccadic eye movement (SEM) abnormalities in schizophrenic patients treated with clozapine, risperidone or sulpiride

Saccadic eye movement (SEM) abnormalities in schizophrenic patients treated with clozapine, risperidone or sulpiride

Structural brain abnormalities in schizophrenic patients with and without cavum septi pellucidi as measured by MRI

Structural brain abnormalities in schizophrenic patients with and without cavum septi pellucidi as measured by MRI

Structure and function of the corpus callosum in schizophrenia: What's the connection?

Tests of both structure and function of the corpus callosum have revealed abnormalities in schizophrenic patients. One such functional test employed lateralised Stroop stimuli presented tachistoscopically, to measure the transfer of interference and facilitation between the cerebral hemispheres. An attempt was made to relate indices of callosal transfer to clinical and demographic variables, including family history, as well as to indices of brain morphology. The latter included ventricle: brain ratio (VBR) measured by computed tomography (CT) scanning on 31 DSMIII schizophrenics, and the cross-sectional area of the corpus callosum from magnetic resonance imaging (MRI), obtained from 20 of these patients. VBR did not relate to functional measures; however, anterior callosal area correlated with indices of callosal connectivity. Patients with auditory hallucinations had smaller anterior callosal areas and tended to show less connectivity. The results show links between functional and structural measures of the corpus callosum, but their precise nature remains unclear.

Schizophrenia: a neurodevelopmental perspective.

The role of aberrant neurodevelopment in the etiology of schizophrenia is reviewed in light of recent neuropathologic, neurochemical, and neuroimaging evidence of cerebral abnormalities in schizophrenic patients. There may exist some genetic defect in the control of brain development. Clinical epidemiologic surveys highlight the importance of obstetric complications, and prenatal exposure to influenza epidemics in contributing to these abnormalities. It is suggested that such environmental hazards and aberrations in the control of early brain development produce the neuronal phenotype that manifests as schizophrenia with early age of onset of symptoms associated with soft neurologic signs and is more common in young males.

Magnetic Resonance Imaging Abnormalities in Lenticular Nuclei and Cerebral Cortex in Schizophrenia

Neuropathologic and brain imaging studies have produced evidence of brain abnormalities in schizophrenic patients, often within the cerebrum's limbic lobe, and, less frequently, within basal ganglia. In the present study we used magnetic resonance imaging morphometric techniques to estimate volumes of specific cerebral structures in schizophrenic patients and age- and sex-matched normal controls. Estimates of the volume of mesial temporal lobe structures were reduced and estimates of the volume of the lenticular nucleus were increased in the schizophrenic patients. There was also evidence of reduced cranial volume in some schizophrenics. The magnitude of the lenticular abnormality, but not the temporal lobe abnormality, was associated with age at first psychiatric contact; earlier onset was associated with larger lenticular nuclei. The possible relevance of these results to neurodevelopmental hypotheses about the pathogenesis of schizophrenia is discussed.

Startle response models of sensorimotor gating and habituation deficits in schizophrenia

Studies of prepulse inhibition and habituation of startle responses elicited by intense stimuli provide some unusual opportunities for cross-species explorations of attentional deficits characteristic of schizophrenic patients. Schizophrenic patients exhibit deficits in both the prepulse inhibition of startle and the habituation of startle. The behavioral plasticity of startle responses and the comparability of the test paradigms used in rats and humans greatly facilitates the development of animal models of specifiable behavioral abnormalities in schizophrenic patients. This review describes two such examples of parallel animal and human models, one involving sensorimotor gating and the other examining behavioral habituation. Evidence is presented supporting the involvement of mesolimbic dopaminergic systems in the modulation of prepulse inhibition or sensorimotor gating and the importance of central serotonergic systems in the habituation of startle.

Relations between orienting response nonresponsiveness and smooth pursuit eye movement abnormalities in schizophrenic patients : David B. Schnur, M.D. (by invitation), Harold A. Sackeim, Ph.D., Alvin S. Bernstein, Ph.D. (by invitation), Sukdeb Mukherjee, M.D., Michael McDonald, B.A. (by invitation), Xavier Amador, Ph.D. (by invitation), Anne Jaeger (by invitation), James Wrable (by invitation) New York State Psychiatric Institute, New York, NY

Relations between orienting response nonresponsiveness and smooth pursuit eye movement abnormalities in schizophrenic patients : David B. Schnur, M.D. (by invitation), Harold A. Sackeim, Ph.D., Alvin S. Bernstein, Ph.D. (by invitation), Sukdeb Mukherjee, M.D., Michael McDonald, B.A. (by invitation), Xavier Amador, Ph.D. (by invitation), Anne Jaeger (by invitation), James Wrable (by invitation) New York State Psychiatric Institute, New York, NY