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Unusually frequent sinistral motor and sighting dominance have sometimes been reported in schizophrenics, although the majority of patients are still dextral. In this study, assessment of lateral dominance also included a measure of grip strength--a potentially more sensitive index of dominance or lateralised impairment; schizophrenics, non-schizophrenic patients (affective disorder), and normal controls were studied. There were no differences in handedness or sighting dominance. Affective patients, particularly bipolar psychotics, had greater right-handed grip superiority than normals or non-paranoid schizophrenics. Paranoid schizophrenics were similar, being significantly greater in right-sided dominance than non-paranoids, who tended toward a smaller value than normals. Hand grip asymmetry was highly correlated with handedness in normals, but not in patients. The possibility is discussed that these results may reflect asymmetrical patterns of cerebral impairment or attentional bias. [ABSTRACT FROM AUTHOR]

The relationship was examined between sinistral eye and hand preference and age at first hospitalisation, clinical course and social competence in chronic schizophrenics. Motor and sighting dominance were assessed in 52 newly admitted chronic schizophrenic males. Left-handedness in this study was associated with inferior social competence, but left-eyedness with later age of first hospitalisation and proportionally less time spent in hospitals. These findings were only true for paranoid schizophrenics. [ABSTRACT FROM AUTHOR]

Differential patterns of EEG alpha asymmetry during verbal and spatial cognitive activity are commonly described and are thought to reflect predominance of left- vs. right-sided cortical activation. Although these patterns have been difficult to elicit reliably in schizophrenics, the authors have previously suggested that clinical status may have confounded results. Therefore, EEG data from 17 additional schizophrenic patients, 16 mood disorder patient controls, and 17 normal controls were used to examine the relationship between severity of schizophrenic symptoms and task induced alpha asymmetry. Subjects performed verbal and spatial tasks during recording of 16-channel EEG. After transformation to the average reference, log alpha power from central and temporal leads was analyzed by MANOVA and MANCOVA. The expected task-side interaction (P < 0.02) was present for the total sample and for each control group when analyzed alone. However, it was only present in schizophrenics when the BPRS score was entered as a covariable. Patterns of correlations between BPRS scores, left temporal alpha power, right/left temporal alpha ratios, and task differences in ratios suggested that higher symptom levels were associated with excessive left-sided activation during spatial activity. This is consistent with other evidence of left hemisphere overactivity in schizophrenics.

In vivo 31Phosphorous magnetic resonance spectroscopic imaging (31P MRSI) was performed on 18 chronic schizophrenic patients and 14 normal controls to determine if there was asymmetry of high-energy phosphorous metabolism in the temporal lobes of schizophrenic patients. Temporal lobe phosphorous metabolites were also correlated with severity of psychiatric symptomatology as assessed by the Brief Psychiatric Rating Scale (BPRS). Schizophrenics demonstrated significantly higher right relative to left temporal phosphocreatine/adenosine triphosphate (PCr/ATP), phosphocreatine/inorganic phosphate (PCr/Pi), and PCr as well as significantly lower right relative to left temporal ATP. There were no asymmetries of temporal lobe phosphorous metabolites in the control group. In addition, both left temporal PCr and the degree of asymmetry of temporal lobe PCr were highly correlated with the thinking disturbance subscale of the BPRS. This study provides further support for temporal lobe metabolic asymmetry in schizophrenia and its possible association with clinical symptoms.

Objective: The authors examined whether there are abnormalities in high-energy phosphorous metabolism in the basal ganglia of schizophrenic patients., Method: In vivo 31P magnetic resonance spectroscopic imaging was performed on 18 chronic schizophrenic patients and 16 healthy comparison subjects. The percentages of total phosphorous signal for phosphomonoesters, inorganic phosphate, phosphodiesters, phosphocreatine, and beta-ATP were calculated., Results: The mean percentages of beta-ATP signal in the right and left basal ganglia were significantly lower for the schizophrenic patients than for the comparison group. No other group differences in phosphorous metabolites and no lateral asymmetries in the schizophrenic group were noted., Conclusions: This preliminary study provides support for abnormal high-energy phosphorous metabolism in the basal ganglia of schizophrenic patients.

In vivo 31Phosphorus magnetic resonance spectroscopic imaging (31P MRSI) was performed on 20 chronic schizophrenic patients and 16 normal controls to determine if there were specific changes in high energy phosphorus and phospholipid metabolism in the frontal lobes of schizophrenic patients. Phosphorous metabolites were assessed in each of the left and right frontal as well as the left and right parietal lobes. Frontal lobe phosphorous metabolites were also correlated with severity of psychiatric symptomatology as assessed by the Brief Psychiatric Rating Scale (BPRS). Schizophrenics demonstrated higher phosphodiesters (PDE) and lower phosphocreatine (PCr) in both the left and right frontal regions compared to controls. There was also lower left frontal inorganic phosphate (Pi) in the schizophrenic group. No group differences were noted in the left or right parietal regions. In addition, right frontal PDE and right frontal PCr were highly correlated with the hostility-suspiciousness and anxiety-depression subscales of the BPRS. This study provides further support for altered frontal lobe phosphorous metabolism in schizophrenia.

Eleven schizophrenic patients and nine normal controls were studied using in vivo 31Phosphorous magnetic resonance spectroscopy (31P MRS) to test the hypothesis of metabolic asymmetry in the temporal lobes in schizophrenia. The controls did not demonstrate any asymmetry of phosphorous metabolite ratios, percentage of phosphorous metabolites, or pH. In the schizophrenics, however, phosphocreatine/beta-adenosine triphosphate (PCr/beta-ATP) and phosphocreatine/inorganic phosphate (PCr/Pi) effects appeared to primarily reflect higher ratios on the right side, while the percentage of beta-ATP appeared to primarily reflect higher relative concentrations in the left temporal lobe. Moreover, significant negative correlations were noted between total Brief Psychiatric Rating Scale scores and PCr/beta-ATP in both the right and left temporal lobes. These results support the hypothesis of an asymmetric distribution of 31P metabolites in the temporal lobe of schizophrenic patients, and also show an association between temporal lobe phosphorous metabolism and the severity of psychiatric symptomatology.

The authors transformed 9 channels of electroencephalogram (EEG) to 10 channels of average reference data and compared EEG asymmetry between medication-free (for 2 weeks) schizophrenic male patients (n = 14), male patients with affective disorder (n = 9), and normal males (n = 13). Multivariate analyses failed to find lateralized differences between groups in resting and task EEG. Neuroleptic treatment (n = 11) was associated with asymmetrical changes in beta power rather than in alpha and theta, as previously reported. There were no relationships between clinical ratings (based on the Brief Psychiatric Rating Scale and subscales) and alpha asymmetry. The authors discuss conflicts with previous findings and the advantages of minimizing reference bias when studying EEG topography.

It has been reported that a large proportion of patients with major psychiatric disorders can recall a short story better if they listen with one ear rather than the other (monaural asymmetry), and that binaural performance is worse than with the better ear alone (binaural inferiority). Blocking the poorer ear with an earplug is said to significantly improve speech comprehension in daily life. Because of the theoretical and practical significance of these reports, we have attempted a replication. Forty-four psychotic patients, primarily schizophrenic, were studied. We found a lower incidence of abnormal monaural asymmetry and binaural inferiority than was previously reported. The incidence remained low whether we considered the entire sample or subgroups defined by diagnosis, chronicity, or age. Retest reliability was poor. We also found that binaural superiority was as common as binaural inferiority, and concluded that the instances of relative binaural inferiority in our sample were primarily due to chance. Differences in methods, subject selection, or medication were considered, but did not clearly account for the discrepancies between our results and previous studies. Future research must focus on establishing the conditions determining reliability.

Lehmann has demonstrated that EEG topography can be used to segment EEG map series into a sequence of spatially stationary segments characterized by location of potential maxima and minima. We employed topographic segmentation techniques to study 9 channel EEGs recorded from 11 medication-free schizophrenic patients and 10 normal controls during resting and active task conditions, retesting 8 patients after neuroleptic treatment. To define EEG segments, average reference potential maps corresponding to global field power peaks in theta, alpha, and low beta activity were classified according to locations of extreme minimum and maximum values. Normals and schizophrenics did not differ in the number or types of switches between segments, or the frequency of hemisphere crossing of potential extrema. However, EEGs of normal subjects were characterized by significantly more (P less than 0.003) unused theta segment types (of a theoretically possible 36). Moreover, medication significantly (P less than 0.02) increased the number of unused theta segment types in EEGs of schizophrenics. We interpret these findings as evidence of increased spatial variability of brain electrical activity in schizophrenics and discuss their functional implications.

In order to evaluate the integrity of their saccadic system, we have examined saccadic eye movements and smooth pursuit in a small group of schizophrenic patients, using precise infrared recording instrumentation. There were no significant differences between mean saccadic latencies of patients and controls. Both groups had mean latencies within the normal range of 200-250 msec. Saccades of schizophrenic patients appeared to have normal trajectories and dynamic characteristics. Three of the six schizophrenic patients and one of the three normal controls had smooth pursuit tracking characterized by saccadic intrusions and saccadic smooth pursuit tracking. Occasional saccadic intrusions and saccadic smooth pursuit tracking appeared in the records of all other subjects, but with considerably lower frequency. These results, emerging from reflected light methods, confirm a previous report of normal saccadic latencies in schizophrenic patients using an electrooculographic technique.

The DSM-III classification of factitious disorders encourages artificial separation into disorders with physical and those with psychologic symptoms. Despite documented examples of similar patients who present with psychiatric complaints, Munchausen's syndrome is usually considered a form of chronic factitious physical disorder. Three patients with both factitious physical and psychologic symptoms are presented. These patients illustrate the importance of focusing on the fundamental behavior of assuming the patient role, rather than on the specific category of symptoms. We recommend that the category of symptoms be used as a modifying statement, rather than defining separate disorders.

We have recently shown that electroencephalogram (EEG) coherence data recorded with common reference methods, including those obtained from schizophrenics, are confounded by power and phase effects. Three published reports using bipolar recordings found that EEG coherence was higher in schizophrenics; however, only medicated patients were studied. To extend these findings, we measured EEG coherence from bipolar EEG recordings in unmedicated schizophrenics (n = 10), affective disorder patients (n = 8), and normal controls (n = 13) during resting and task conditions. Seven schizophrenics were restudied after a period of neuroleptic treatment. Schizophrenics had higher across-task interhemispheric (p less than 0.05) and intrahemispheric (p less than 0.04) coherence in the theta band and tended to have higher intrahemispheric alpha coherence (p less than 0.08). Medication treatment was associated with clinical improvement and increases in spectral power, but not with changes in coherence values. These results confirm those obtained by earlier investigations and suggest that increased coherence reflects the presence of anomalous cortical organization in schizophrenics rather than medication effects or transient states related to acute clinical disturbance.

The author reviewed literature implicating a disturbance located in the left cerebral hemisphere in the pathogenesis of schizophrenia. Studies of the psychiatric sequelae of lateralized organic cerebral disease were considered, as well as neurological, neurophysiological, and neuroanatomic studies of psychiatric patients. In general, abnormalities in cerebral hemispheric asymmetry appear to be common among psychiatric patients, particularly those with personality disorders, some affective disorders, autistic children, and, at least, some schizophrenics. The latter may include those with milder, less chronic illnesses. A specific relationship between the side of unilateral cerebral impairment and diagnosis suggested by some authors is not consistently supported by the literature, however. The implications of these findings are discussed in terms of neurodevelopmental issues in schizophrenia.

Lateral asymmetry of electroencephalographic (EEG) spectra was assessed in schizophrenic patients compared to normal controls. Ten predominantly unmedicated schizophrenic inpatients and nine normal controls performed monitored cognitive tasks during bilateral recording of EEG from parietal and temporal sites. Lateralization of EEG power in five frequency bands was compared between the groups; separate analyses were performed for linked ears and vertex references. A subsample of schizophrenic patients was restudied after a period of neuroleptic treatment. All significant group differences were obtained with the linked ears reference only. Pretreatment schizophrenics manifested relatively less alpha power over the right hemisphere during all conditions than controls, particularly in the parietal leads. After treatment, there was a significant shift in alpha lateralization toward the control values. These latter effects were also present in the theta frequency band to a lesser extent.

The underlying diagnosis of Capgras delusion is not found to be exclusively paranoid schizophrenia, nor is the sex exclusively female, as once was believed. Organic factors play a predominant role in many patients, and 41% of the cases are males. The age at diagnosis in those considered to be schizophrenic is older than is usually expected.

Using precise infrared recording instrumentation, we measured the eye-movement patterns in six schizophrenic patients who were taking medication and found saccadic intrusions and saccadic smooth-pursuit tracking in three. This defined some of the eye-movement irregularities reported previously by many investigators. A variety of eye-movement functions in addition to smooth pursuit exhibited these abnormalities, including fixation, vergence, and head-eye pursuit. Saccadic intrusions or saccadic pursuit also occurs in a number of neuro-ophthalmologic disorders, and occasionally in healthy normal subjects. Thus, these eye-movement abnormalities do not occur exclusively in schizophrenia.

Studies to determine the validity of the Mini-Mental State Examination (MMSE) and the Cognitive Capacity Screening Examination (CCSE) have indicated unacceptably high false-negative rates for these tests. To determine whether a new examination, the Neurobehavioral Cognitive Status Examination (NCSE), is more sensitive in the detection of cognitive dysfunction, we compared the three examinations in 30 patients with documented brain lesions. The CCSE had a false-negative rate of 53%; the MMSE, of 43%; and the NCSE, of 7%. The sensitivity of the NCSE is derived from two features of its design: the use of independent tests to assess skills within five major areas of cognitive functioning, and the use of graded tasks within each of these cognitive domains.

While stimuli of lower spatial frequency often result in faster responses, this is not invariably the case. Some individuals respond faster to high frequency stimuli on tasks for which most others respond faster to low frequency stimuli. Past experience can also determine the degree to which a low frequency stimulus will mask a high frequency stimulus. These observations suggest that the effects of spatial frequency on visual information processing are under the control of higher level cognitive operations.

EEG was recorded from bilateral frontal, central, temporal, and parietal leads (referenced to or transformed to a vertex reference) during cognitive activity in 13 normal controls, ten schizophrenics, and eight patients with affective disorders. All subjects were male and right-handed, and patients had been free of psychotropic medications for at least 2 weeks. A verbal (copying text) and spatial (copying shapes) task were matched for stimulus presentation and motor output. The number and rate of correct responses were recorded for each normal subject and 11 of the patients. As reported by others, normal subjects manifested a significant difference in alpha asymmetry between the tasks, reflecting relatively greater alpha suppression over the left hemisphere during the verbal task compared to the spatial task (P less than 0.05). This effect was not significant in either patient group. However, analysis of seven schizophrenics after neuroleptic treatment revealed robust effects of task on alpha asymmetry similar to that present in the normal control group (P less than 0.02). The results suggest that abnormal task-related brain lateralization may be present in untreated schizophrenic patients, but it is state dependent and does not reflect permanent patterns of brain organization.

Coherence analysis of the EEG is used to study the coupling between cortical regions. High coherence between signals recorded at 2 electrodes is interpreted as evidence for neuroanatomic connections between the cortical areas underlying the electrodes. When common reference recordings are used, coherence measures the relationship between 2 time series, each of which is the difference between 2 signals measured at the scalp and is confounded by spectral power and phase at the recording and reference electrodes. Using multi-channel EEG data from 3 subjects, we illustrate the confounding of common reference data coherence computations and demonstrate the extreme effects of power and phase changes on coherence by simulating these changes in the EEG data. Common reference coherence data can be either inflated or deflated as a consequence of activity (i.e., spectral power) at the reference. Phase relationships among the reference and recording time series modulate the power effects on coherence. Both the power and phase effects can vary dramatically across frequencies, having profound and complicated effects on the shape of the coherence function. Based on these considerations, we conclude that common reference coherence data must be interpreted very cautiously and recommend that a new body of EEG coherence data must be gathered using reference-free recording methods before the utility of EEG coherence analysis for understanding brain function can be determined.