Emotional processing in schizophrenia across cultures: standardized measures of discrimination and experience

Schizophrenia appears quite similar across a range of cultures. However, variability has been noted, and understanding the variant and invariant features of the disorder is necessary for elucidating its biological and environmental basis. Evidence of prominent emotion processing deficits in schizophrenia, including perceptual and experiential aspects, led us to extend the paradigm of standardized measures cross-culturally. We assessed performance of American, German, and Indian patients with schizophrenia and healthy controls on standardized emotion discrimination and experience (mood induction) procedures using happy, sad, and neutral facial expressions of Caucasian actors. Participants were 80 Americans (40 patients; 40 controls), 48 Germans (24 patients; 24 controls), and 58 Indians (29 patients; 29 controls). Face discrimination performance was impaired across patient groups, but was most impaired in those of Indian origin. Lower performance was also found in Indian controls, relative to their American and German counterparts. Mood induction produced weaker effects in all patient groups relative to their respective controls. The results supported the feasibility of cross-cultural comparisons and also emphasized the importance of poser ethnic background for facial affect identification, while poser ethnicity was less consequential for mood induction effects. Emotion processing deficits in schizophrenia may add to the clinical burden, and merit further examination.

P300 subcomponent abnormalities in schizophrenia: III. Deficits In unaffected siblings of schizophrenic probands

BACKGROUND

Reduced P300 amplitude is a robust finding in patients with schizophrenia. In previous investigations, we reported reductions of specific subcomponents of the auditory oddball P300 that were independent of acute symptomatology and persistent over time, consistent with a trait abnormality. To clarify whether these stable deficits represented genetic markers of vulnerability to schizophrenia, event-related brain potentials (ERPs) from patients were compared to those from their own healthy siblings and unrelated control subjects.

METHODS

Auditory P300 ERPs were acquired from 11 schizophrenic patients, 12 healthy siblings and 23 matched control subjects. Five P300 subcomponents were identified using current source density measures: frontal, bilateral parietal, and bilateral temporal.

RESULTS

Consistent with previous reports, patients had reduced parietal and frontal P300 amplitudes. The healthy siblings of the schizophrenic probands had an isolated reduction of the frontal P300.

CONCLUSIONS

Frontal P300 amplitude is a potential endophenotypic marker of genetic vulnerability to schizophrenia in individuals who otherwise show no evidence of clinical symptomatology. Given the functional interpretation of the frontal P300 as a physiological correlate of cognitive orienting, this supports the hypothesis that impairments of the neural substrate underlying attentional mechanisms are selective indicators of genetic susceptibility to schizophrenia in high-risk individuals.

Sex differences in brain-behavior relationships between verbal episodic memory and resting regional cerebral blood flow

Women have better verbal memory, and higher rates of resting regional cerebral blood flow (rCBF). This study examined whether there are also sex differences in the relationship between verbal episodic memory and resting rCBF. Twenty eight healthy right-handed volunteers (14 male, 14 female) underwent a neuropsychological evaluation and a Positron Emission Tomography (PET) (15)O-water study. Immediate and delayed recall was measured on the logical memory subtest of the Wechsler Memory Scale - Revised (WMS-R), and on the California Verbal Learning Test (CVLT). Resting rCBF (ml/100 g/min) was calculated for four frontal, four temporal, and four limbic regions of interest (ROIs). Women had better immediate recall on both WMS-R and CVLT tasks. Sex differences in rCBF were found for temporal lobe regions. Women had greater bilateral blood flow in a mid-temporal brain region. There were also sex differences in rCBF correlations with performance. Women produced positive correlations with rCBF laterality in the temporal pole. Greater relative CBF in the left temporal pole was associated with better WMS-R immediate and delayed recall in women only. These results suggest that trait differences in temporal pole brain-behavior relationships may relate to sex differences in verbal episodic memory.

Working memory constrains abstraction in schizophrenia

BACKGROUND

Abstraction has long been considered an area of differential cognitive deficit in schizophrenia, primarily because of patients' poor performance on the Wisconsin Card Sorting Test (WCST). Yet, the complexity and multidimensional nature of the WCST increases the likelihood that several different cognitive processes, perhaps mediated by different neural systems, are being tapped.

METHODS

In the current study, the Abstraction and Working Memory (AIM) task was designed to disentangle abstraction and working memory so that the effects of each cognitive domain could be independently analyzed. The AIM task and a battery of neuropsychological tests were administered to 62 patients with schizophrenia and 62 matched healthy volunteers.

RESULTS

Whereas patients with schizophrenia demonstrated deficits in simple abstraction, they were disproportionately impaired with the addition of a minimal memory requirement.

CONCLUSIONS

Group differences on WCST performance appear to be attributable to patients' inability to maintain information over a short delay, before that information is used for more complex cognitive operations.

Reduced gray matter volume in schizophrenia

BACKGROUND

There is emerging evidence that gray matter (GM) is reduced in patients with schizophrenia. Information on the extent of global differences in the 3 principal supertentorial compartments is necessary for interpretation of regional effects. The relation of GM reduction to clinical status and neurocognition also requires examination.

METHODS

Magnetic resonance imaging, neurocognitive measures, and clinical assessment of symptoms and functioning were obtained for 130 patients (51 neuroleptic naive, 79 previously treated) and 130 healthy controls (75 men, 55 women in each group).

RESULTS

Overall GM volume was reduced in patients compared with controls. This was evident in men (6% reduction) and women (2% reduction) and was already evident at the first presentation of neuroleptic-naive patients. The reduction sustained correction for age and total intracranial volume. Compartmental volumes did not correlate with the severity of positive (r, -0.08 to 0.23) or negative (r, -0.01 to -0.07) symptoms, but GM volume was associated with better premorbid functioning in women (r, 0.36-0.51). Small but significant correlations (r, 0.19-0.44) were observed between GM volume and performance in 6 neurocognitive domains. These correlations varied by diagnosis, most higher in patients, and were moderated by sex.

CONCLUSIONS

Gray matter volume reduction in schizophrenia is already evident in men and women at first presentation. While this reduction is not correlated with symptom severity, it is associated with cognitive performance. Since GM development accelerates in the later part of gestation, while white matter growth is primarily postnatal, the results may support the hypothesis that neurodevelopmental processes relate to GM deficit.

Olfactory dysfunction in schizophrenia: a qualitative and quantitative review

Olfactory dysfunction in patients with schizophrenia has been a topic of increasing interest, with deficits in odor identification, detection threshold sensitivity, discrimination, and memory being reported. Despite increasing knowledge, controversy has existed about possible differential deficits among olfactory tests as well as the influences of gender, smoking, and medication status on olfactory measures. To help elucidate some of this controversy, we conducted a qualitative and quantitative (meta-analytic) review of the English language literature on olfaction in schizophrenia. Moderator variables such as gender, medication status, and smoking history were also examined. Results indicated that substantial olfactory deficits, across all domains, are observed in patients with schizophrenia. No differential deficits were observed across domains of odor identification, detection threshold sensitivity, discrimination, and memory. The influences of gender, medication status, and smoking on effect sizes were not significant across studies. This supports the hypothesis of primary dysfunction in the olfactory system that is regulated by brain regions where structural and functional abnormalities have also been reported in neuroimaging studies.

Sex differences in brain gray and white matter in healthy young adults: correlations with cognitive performance

Sex-related differences in behavior are extensive, but their neuroanatomic substrate is unclear. Indirect perfusion data have suggested a higher percentage of gray matter (GM) in left hemisphere cortex and in women, but differences in volumes of the major cranial compartments have not been examined for the entire brain in association with cognitive performance. We used volumetric segmentation of dual echo (proton density and T2-weighted) magnetic resonance imaging (MRI) scans in healthy volunteers (40 men, 40 women) age 18-45. Supertentorial volume was segmented into GM, white matter (WM), and CSF. We confirmed that women have a higher percentage of GM, whereas men have a higher percentage of WM and of CSF. These differences sustained a correction for total intracranial volume. In men the slope of the relation between cranial volume and GM paralleled that for WM, whereas in women the increase in WM as a function of cranial volume was at a lower rate. In men the percentage of GM was higher in the left hemisphere, the percentage of WM was symmetric, and the percentage of CSF was higher in the right. Women showed no asymmetries. Both GM and WM volumes correlated moderately with global, verbal, and spatial performance across groups. However, the regression of cognitive performance and WM volume was significantly steeper in women. Because GM consists of the somatodendritic tissue of neurons whereas WM comprises myelinated connecting axons, the higher percentage of GM makes more tissue available for computation relative to transfer across distant regions. This could compensate for smaller intracranial space in women. Sex difference in the percentage and asymmetry of the principal cranial tissue volumes may contribute to differences in cognitive functioning.

Neuropsychological laterality indices of schizophrenia: interactions with gender

Neurobehavioral laterality indices were examined across motor, sensory, language versus spatial, and verbal memory versus spatial memory domains for 75 patients with schizophrenia (45 men, 30 women) and 75 demographically matched healthy controls. Patients were impaired across tasks, and laterality results varied by domain. There was no evidence for diagnosis by hemisphere interactions in motor, sensory, or memory tasks. However, patients were more impaired in language than in spatial domains, which suggests relatively greater left hemisphere dysfunction. This finding was mediated by the sex of the participant. While patients as a group showed greater language than spatial impairment, male patients showed expected superiority in spatial relative to language performance, whereas female patients performed the same on both functions. These results underscore the importance of examining sex differences in laterality effects. The findings also demonstrate that, although the left hemisphere model of schizophrenia may be partially supported by data on higher cognitive functions, this support does not extend to more basic motor and sensory domains.

Laterality in functional brain imaging studies of schizophrenia

Brain laterality in schizophrenia has been examined through the application of functional neuroimaging methods. These methods have included the 133Xenon technique for measuring cerebral blood flow (CBF); positron emission tomography for assessing rates of glucose metabolism, CBF, and neuroreceptor functioning; single photon emission computerized tomography for studying CBF and neuroreceptors; and functional magnetic resonance imaging for measuring changes attributable to CBF. This article highlights the application of this technology in schizophrenia research, emphasizing more recent studies that have evaluated hemispheric differences. There is evidence for lateralized abnormalities in some studies that have examined this dimension. In general, the results implicate abnormalities in left hemispheric activity. Recent advances in basic and clinical neuroscience provide an opportunity for focused application of functional imaging in neurobiological studies of schizophrenia.

Is Schizophrenia a lateralized brain disorder? Editor's introduction

Lateralization of brain function was established on the basis of clinical-pathological correlations over a century ago. In the past two decades, this line of research has attempted to link the complex behaviors evident in schizophrenia to the failure to develop and maintain a normal pattern of hemispheric activity. This issue of Schizophrenia Bulletin reviews and presents data from multiple perspectives of methods applied to the study of laterality in schizophrenia. Brain disorders affecting systems that modulate complex behavior are commonly related to laterality. Therefore, this dimension of brain function merits further investigation in schizophrenia.

Depression in temporal lobe epilepsy before epilepsy surgery

PURPOSE

This study examined the association of depression with laterality of epilepsy surgery in patients with temporal lobe epilepsy before standard lobectomy.

METHODS

Forty-nine patients presented for EEG telemetry for localization of epilepsy and eventual temporal lobectomy. Patients underwent routine neuropsychiatric evaluation blinded for epileptic focus, including ratings on depression. Patients were grouped according to right (n = 25, M = 10/F = 15) and left (n = 24, M = 13/F = 11) temporal lobectomy. Analysis of variance included side of surgery as grouping variable and sex, general depressive, cognitive depressive, and vegetative depressive symptoms as dependent variables. Chi2 analyses included categoric variables of sex, handedness, education, neuropathologic findings, and current affective disorders. t Tests were performed on variables of age, epilepsy duration, and cognitive function.

RESULTS

Right and left temporal epilepsy groups did not differ with regard to sex, handedness, age, duration of epilepsy, education, cognitive function, and neuropathology. Patients with right temporal epilepsy rated higher on general, cognitive. and vegetative depression scores. Women scored higher on general, cognitive, and vegetative depression scores. Current affective disorders were more common in the right temporal epilepsy group.

CONCLUSIONS

Depression ratings and diagnoses were more prominent in patients with right temporal lobe epilepsy and in women in particular. The strength of this laterality finding lies in the selection of patients, as all underwent epilepsy surgery. The finding on gender difference partly reflects the higher incidence of depression in women and needs further exploration. The laterality finding contrasts with recent findings in epilepsy, stroke, and trauma that associate depression with left hemispheric lesions. However, our results are consistent with findings in electrically hyperactive lesions such as gelastic and dacrystic epilepsy.

Proton magnetic resonance spectroscopy in the frontal and temporal lobes of neuroleptic naive patients with schizophrenia

Studies with proton magnetic resonance spectroscopy (MRS) have reported abnormalities in N-acetyl-aspartate (NAA), amino acids (AA) and choline (Cho) to creatine (Cr) ratios associated with schizophrenia. We report data on the three ratios in a sample of 18 neuroleptic naive patients with first-episode schizophrenia (eight studied in the dorsolateral prefrontal and 10 in the midtemporal lobe) and 24 healthy controls (14 studied in prefrontal and 10 in midtemporal lobes). Frontal lobe proton spectra were acquired with the stimulated-echo acquisition mode (STEAM) pulse sequence (echo time 21 ms, repetition time 2 s). Temporal lobe proton spectra were acquired with the point-resolved spectroscopy (PRESS) pulse sequence (echo time 16-21 ms, repetition time 2 s). Upon comparison with normal controls, NAA/Cr ratios were reduced in patients both for the frontal and the temporal lobe. By contrast, Cho/Cr ratios were slightly elevated in frontal and reduced in temporal lobes; whereas, AA/Cr ratios were normal in frontal and markedly increased in the temporal lobe. The reduced NAA/Cr ratios suggest lower neuronal viability in patients and is consistent with findings of reduced brain volume in both frontal and temporal regions.

Subcortical MRI volumes in neuroleptic-naive and treated patients with schizophrenia

OBJECTIVE

This study examined whether subcortical volumes of the basal ganglia and thalamus in schizophrenic patients are related to neuroleptic exposure and symptom severity.

METHOD

Basal ganglia substructures and thalamic volumes were measured with magnetic resonance imaging in 96 patients with schizophrenia (50 men and 46 women) and 128 healthy comparison subjects (60 men and 68 women). Twenty-one of the patients were neuroleptic-naive; of the 75 previously treated patients, 48 had received typical neuroleptics only, and 27 had received typical and atypical neuroleptics. The relation of volume measures to treatment status, exposure to neuroleptics, and symptoms was examined.

RESULTS

The neuroleptic-naive patients did not differ from the healthy comparison subjects in subcortical volumes except for lower thalamic volume. In the neuroleptic-naive group, volumes did not correlate with severity of negative symptoms, but higher volumes in both the thalamus and the putamen were associated with more severe positive symptoms. The previously treated group showed higher volumes in the putamen and globus pallidus than the healthy comparison subjects and the neuroleptic-naive patients. In the treated group, a higher dose of a typical neuroleptic was associated with higher caudate, putamen, and thalamus volumes, whereas a higher dose of an atypical neuroleptic was associated only with higher thalamic volume. Higher subcortical volumes were mildly associated with greater severity of both negative and positive symptoms.

CONCLUSIONS

Increased subcortical volumes in treated schizophrenic patients seem to be medication-induced hypertrophy. This hypertrophy could reflect structural adaptation to receptor blockade and may moderate the effects of neuroleptic treatment.

Regional gray matter, white matter, and cerebrospinal fluid distributions in schizophrenic patients, their siblings, and controls

BACKGROUND

Cortical gray matter volume reductions and cerebrospinal fluid (CSF) volume increases are robust correlates of schizophrenia, but their sources have not been established conclusively.

METHODS

Structured diagnostic interviews and magnetic resonance imaging scans of the brain were obtained on 75 psychotic probands (63 with schizophrenia and 12 with schizoaffective disorder), ascertained so as to be representative of all such probands in a Helsinki, Finland, birth cohort; 60 of their nonpsychotic full siblings; and 56 demographically similar control subjects without a personal or family history of treated psychiatric morbidity.

RESULTS

Patients with schizophrenia and their siblings exhibited significant reductions in cortical gray matter volume and significant increases in sulcal CSF volume compared with controls. The patients, but not their siblings, also exhibited significant reductions in white matter volume and significant increases in ventricular CSF volume. Regional effects were most robust when component volumes were expressed as percentages of overall regional volumes; in this case, for patient and sibling groups, gray matter volume reductions and sulcal CSF volume increases were significantly more pronounced in the frontal and temporal lobes than in the remainder of the brain. None of the group differences varied significantly by sex or hemisphere.

CONCLUSIONS

Structural alterations of the cerebral cortex, particularly in the frontal and temporal lobes, are present in patients with schizophrenia and in some of their siblings without schizophrenia; such changes are thus likely to reflect genetic (or shared environmental) effects. Ventricular enlargement is unique to the clinical phenotype and is thus likely to be affected primarily by nonshared causative factors.

MMPI-2 characteristics of adults diagnosed with attention deficit disorder

Attention Deficit Disorder (ADD) has been increasingly recognized as extending into adulthood, affecting occupational, interpersonal, and psychological functioning. The Minnesota Multiphasic Personality Inventory (MMPI) and its revision (MMPI-2) have been widely used in the assessment of patients with psychiatric disorders, but few studies have attempted to characterize the personality profiles of individuals with ADD and none have used the MMPI-2. Thirty-three patients with ADD and 33 schizophrenia patients were compared to 46 healthy control subjects on the MMPI-2 validity, clinical and Harris-Lingoes scales. With the exception of significantly lower scores for general affective distress (F), thought disorder (Sc), and paranoia (Pa), ADD subjects demonstrated remarkably similar profiles to those seen in the schizophrenia group. Significant differences between the three groups were found on a majority of the clinical scales, with ADD subjects showing similar profile elevations as schizophrenic subjects on both clinical- and sub-scales. These results were consistent with previous research using the original MMPI in adults with ADD, and confirm that examination of MMPI-2 profiles may be a useful diagnostic aid for this disorder.

Frontotemporal cerebral blood flow change during executive and declarative memory tasks in schizophrenia: a positron emission tomography study

Schizophrenia affects prefrontal and temporal-limbic networks. These regions were examined by contrasting regional cerebral blood flow (rCBF) during executive (Wisconsin Card Sorting Test [WCST]), and declarative memory tasks (Paired Associate Recognition Test [PART]). The tasks, and a resting baseline, were administered to 15 patients with schizophrenia and 15 healthy controls during 10 min positron emission tomography 15O-water measures of rCBF. Patients were worse on both tasks. Controls activated inferior frontal, occipitotemporal, and temporal pole regions for both tasks. Similar results were obtained for controls matched to level of patient performance. Patients showed no activation of hypothesized regions during the WCST and activated the dorsolateral prefrontal cortex during the PART. On the PART, occipitotemporal activation correlated with better performance for controls only. Better WCST performance correlated with CBF increase in prefrontal regions for controls and in the parahippocampal gyrus for patients. Results suggest that schizophrenia may involve a breakdown in the integration of a frontotemporal network that is responsive to executive and declarative memory demands in healthy individuals.

Premorbid educational attainment in schizophrenia: association with symptoms, functioning, and neurobehavioral measures

BACKGROUND

The purpose of this study was to examine the association of educational attainment with phenomenology and neurobehavioral measures assessing brain structure and function in schizophrenia.

METHODS

One hundred sixty-two patients with schizophrenia were divided into two groups on the basis of educational attainment: > or = 13 years of education was the cutoff between the high and low groups. The two education groups were compared on symptomatology, functioning, and subsamples on neuropsychological profile, brain volume by magnetic resonance imaging, and brain metabolism by fluorodeoxyglucose positron-emission tomography.

RESULTS

The patients with more education had lower levels of psychotic symptomatology than their counterparts with less education. This was most evident for affective flattening, alogia, avolition, and bizarre behavior. The higher education group also had better ratings on premorbid adjustment, and the engagement and vocational factors of the Quality of Life Scale. Patients in the high education group also performed better on the neuropsychological battery. There were no brain volume differences or differences in brain metabolism between the two education groups.

CONCLUSIONS

Education is an important indicator of premorbid function and is related to the clinical presentation of schizophrenia.

P50 abnormalities in schizophrenia: relationship to clinical and neuropsychological indices of attention

While the P50 component (50-60-ms latency) of the auditory evoked potential has been reported as abnormal in schizophrenia, few studies have examined the relationship between this abnormality and clinical or neuropsychological measures. To examine these possible relationships, mid-latency auditory evoked potentials were recorded at the CZ recording site of 47 patients with schizophrenia in response to binaural clicks presented at three stimulus rates: 1, 5 and 10/sec. A sub-sample of patients were then divided into high- (n = 15) and low-P50 abnormality (n = 16) groups based on a median split of the P50 amplitude at a rate of 10/sec (a greater amplitude at this rate suggests a greater abnormality in recovery) of the entire sample. Only those patients with complete neuropsychological and clinical data and who were reasonably matched on demographic dimensions were included. A multivariate analysis of variance of 11 neuropsychological function profile scores showed a significant group x global score interaction (Hotelling t = 3.97, p < 0.005). The high-abnormality group had relatively greater deficits for attention profile scores than for the remaining neuropsychological measures. An analysis of global subscores for SAPS and SANS clinical measures revealed a significant difference only for the SANS attention subscale (p < 0.05). The high-abnormality group was rated as more severe on the attention measure. These convergent findings across both phenomenological and neuropsychological measures suggest that abnormalities in P50 recovery may be linked to deficits in attention processes in schizophrenia.

Frontotemporal cerebral blood flow change during executive and declarative memory tasks in schizophrenia: a positron emission tomography study

Schizophrenia affects prefrontal and temporal-limbic networks. These regions were examined by contrasting regional cerebral blood flow (rCBF) during executive (Wisconsin Card Sorting Test [WCST]), and declarative memory tasks (Paired Associate Recognition Test [PART]). The tasks, and a resting baseline, were administered to 15 patients with schizophrenia and 15 healthy controls during 10 min positron emission tomography 15O-water measures of rCBF. Patients were worse on both tasks. Controls activated inferior frontal, occipitotemporal, and temporal pole regions for both tasks. Similar results were obtained for controls matched to level of patient performance. Patients showed no activation of hypothesized regions during the WCST and activated the dorsolateral prefrontal cortex during the PART. On the PART, occipitotemporal activation correlated with better performance for controls only. Better WCST performance correlated with CBF increase in prefrontal regions for controls and in the parahippocampal gyrus for patients. Results suggest that schizophrenia may involve a breakdown in the integration of a frontotemporal network that is responsive to executive and declarative memory demands in healthy individuals.

Leukocyte differentials predict short-term clinical outcome following antipsychotic treatment in schizophrenia

BACKGROUND

The majority of patients with schizophrenia and many of their unaffected siblings exhibit a relative granulocytosis and lymphopenia. To characterize these abnormalities better, we examined leukocyte differentials and organ nonspecific autoantibodies in relationship to intake phenomenology and short-term clinical outcome.

METHODS

We studied patients with schizophrenia (n = 81) and their siblings (n = 18). At intake assessment, about one-half of the probands (n = 38) were neurolepticnaive first-episode patients; the remainder were medication-free for at least 2 weeks. Hematologic indices were obtained at intake assessment, and psychiatric symptomatology was assessed at baseline and following 6 months of clinically determined treatment.

RESULTS

A relative granulocytosis and lymphopenia prospectively predicted poorer recovery in positive, but not negative, symptoms after 6 months of antipsychotic treatment. Abnormal leukocyte proportions were specific to patients who presented with clinically significant positive symptomatology at intake. In contrast, clinically significant negative symptoms were only evident in a small subgroup of patients who were positive for antinuclear autoantibodies and/or rheumatoid factor.

CONCLUSIONS

Future research should further test the hypothesis that a relative granulocytosis and lymphopenia reflect genetic loading for the pathophysiologic determinants of positive symptoms. Future research also should determine the etiologic significance of organ nonspecific autoimmunity in predominantly negative symptom schizophrenia.

Absence of neurodegeneration and neural injury in the cerebral cortex in a sample of elderly patients with schizophrenia

BACKGROUND

The cognitive and functional deterioration that is observed in many "poor-outcome" patients with schizophrenia suggests a neurodegenerative process extending into late life. Previous diagnostic studies have excluded known neurodegenerative diseases as explanations for this dementia. However, we hypothesized that relatively small accumulations of age- or disease-related neurodegenerative lesions occurring in an otherwise abnormal brain could result in deterioration in schizophrenia.

METHODS

Postmortem studies were conducted using 23 prospectively accrued elderly persons with chronic schizophrenia for whom clinical ratings had been determined before death, 14 elderly control patients with no neuropsychiatric disease, and 10 control patients with Alzheimer disease. Immunohistochemistry and unbiased stereological counting methods were used to quantify common neurodegenerative lesions (ie, neurofibrillary tangles, amyloid plaques, and Lewy bodies) and cellular reactions to a variety of noxious stimuli (ubiquitinated dystrophic neurites, astrocytosis, and microglial infiltrates) in the ventromedial temporal lobe and the frontal and the calcarine (primary visual) cortices.

RESULTS

No statistically significant differences were found between the patients with schizophrenia and the control patients without neuropsychiatric disease for the densities of any of the markers, while both groups exhibited fewer lesions than did the control group with Alzheimer disease. Correlation analyses in the schizophrenia sample failed to identify significant correlations between cognitive and psychiatric ratings and densities of any of the neuropathologic markers.

CONCLUSIONS

No significant evidence of neurodegeneration or ongoing neural injury in the cerebral cortex was found in this sample of elderly persons with schizophrenia. Furthermore, the behavioral and cognitive deterioration observed in late life did not correlate with age-related degenerative phenomena.

Depression in schizophrenia: II. MRI and PET findings

BACKGROUND

Despite consistent descriptions of depressive symptoms in schizophrenia, little is known about their neurobiology. The purpose of this study was to examine the association of depression in schizophrenia with measures of brain anatomy and metabolism.

METHODS

Seventy-nine patients were grouped according to their ratings on the Hamilton Depression Rating Scale (HDRS): > or = 18 was the cutoff between the "high" and "low" depression groups. All patients underwent clinical and magnetic resonance imaging (MRI) evaluation, and a subsample of 37 underwent 2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) measurements of cerebral glucose metabolism.

RESULTS

The high depression group had larger bilateral temporal lobe volumes and decreased laterality (left minus right of metabolism in the anterior cingulate).

CONCLUSIONS

The neurobiology of depression in schizophrenia thus seems to share features with major depression due to other disease states.

A follow-up magnetic resonance imaging study of schizophrenia. Relationship of neuroanatomical changes to clinical and neurobehavioral measures

BACKGROUND

Cross-sectional neuroanatomical studies have reported abnormalities in schizophrenia that relate to disease variables. Longitudinal neuroimaging investigations that integrate anatomical, clinical, and neurobehavioral measures may help clarify the pathogenesis of schizophrenia.

METHODS

Magnetic resonance brain imaging and neurobehavioral studies were conducted at baseline and after 30.63 +/- 12.92 months (mean +/- SD) in 40 patients with schizophrenia (23 men and 17 women) and 17 healthy controls (13 men and 4 women). The schizophrenia group included 20 first-episode and 20 previously treated subjects. Volumes of whole-brain, cerebrospinal fluid, and frontal and temporal lobes were measured. The severity of negative and positive symptoms was assessed, medications were monitored, and neurobehavioral functioning in 8 domains was evaluated.

RESULTS

Both first-episode and previously treated patients had smaller brains and frontal and temporal lobes than controls at intake. Longitudinally, reduction in frontal lobe volume was found only in patients, whereas temporal lobe reduction was also seen in controls. The association between volume reduction and symptom changes differed between patient groups, but volume reduction was associated with decline in some neurobehavioral functions in both groups. Exploratory analysis suggested that neuroleptic dose is correlated with changes in all 3 domains.

CONCLUSIONS

The existence of neuroanatomical and neurobehavioral abnormalities in patients with first-episode schizophrenia indicates that the brain dysfunction occurred before clinical presentation. However, there is also evidence of progression, in which anatomical changes may affect some clinical and neurobehavioral features of the illness in some patients.