Symptomatic patients after craniectomy

Various surgical procedures in neurosurgery end with cranial vault defects. It is generally believed that the reason for repair of the skull defect is cosmetic or protective. There is evidence, however, that in selected cases neurologic deterioration can be reversed by cranioplasty. In the sinking scalp flap syndrome the deterioration has been thought to be related to the concavity of the skin flap and underlying brain tissue secondary to atmospheric pressure and also to the in-and-out displacement of the brain through the skull defect. Five cases of symptomatic patients after craniectomy are reported, of which all had a neurologic deterioration that was improved by cranioplasty.

Iodine-123-IPT SPECT imaging of CNS dopamine transporters: nonlinear effects of normal aging on striatal uptake values

Iodine-123-labeled IPT (N-(3-iodopropen-2-yl)-2 beta-carbomethoxy-3 beta-(4-chlorophenyl)tropane) is an analog of cocaine that selectively binds the presynaptic dopamine transporter. This study sought to characterize changes in the striatal uptake of IPT with normal aging.

METHODS

The sample included 18 healthy human volunteers. Their ages ranged from 19 to 67 yr. Dynamic SPECT scans of the brain were acquired with about 185 MBq (5 mCi) of IPT on a triple-headed camera. The images were reconstructed with a three-dimensional restorative filter and corrected for attenuation. The mean concentration of radioactivity [microCi/ml] was measured in the head of the caudate and body of the putamen. The remainder of the supratentorial brain was used as a reference.

RESULTS

The specific uptake of IPT was higher in the caudate than in the putamen of each subject. It decreased significantly with age in both regions. The mean specific uptake in seven volunteers who were less than 30 yr old was 17.6 +/- 4.9 in the caudate and 13.3 +/- 4.0 in the putamen, compared to only 11.97 +/- 3.30 and 7.8 +/- 2.68, respectively, in the six middle-aged subjects (t = 2.53 and 2.90, df = 11, p = 0.027 and 0.014). However, there were no significant differences between the six middle-aged subjects and the five volunteers who were older than 60 yr, whose respective means were 9.0 +/- 1.6 and 6.2 +/- 0.7 (t = 1.83 and 1.28, df = 9, p = 0.10 and 0.23). The results were supported by regression analysis, which indicated that changes with age were not optimally described as a linear function when compared to several nonlinear alternatives. The fit improved when the models accounted for relatively rapid rates of decline during young adulthood, followed by less rapid decline throughout middle age.

CONCLUSION

The results are consistent with the findings from previous studies that have shown that the specific uptake values for radiopharmaceuticals that bind the dopamine transporter decline with advancing age. However, results of this study suggest that the effects of aging may be nonlinear and regionally distinct.

Vulnerability to tardive dyskinesia development in schizophrenia: an FDG-PET study of cerebral metabolism

An understanding of the development of tardive dyskinesia (TD) may require prospective studies assessing the relationship of brain function measures to behavior. This study was undertaken to determine whether predisposition to the development of TD is related to abnormalities of cerebral 18F-labeled 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) measures in schizophrenia. A group of 42 patients without TD underwent FDG PET scanning for measuring cerebral metabolism as well as neuropsychological evaluation and magnetic resonance imaging. Patients were assessed longitudinally for TD development. Eight patients developed TD within 3 years. They were matched to eight patients without TD. Glucose metabolic rates and region/ whole brain ratios were examined in 38 regions of interest per hemisphere. Whole brain metabolism did not differ between the two groups. However, relative hypermetabolism in temporolimbic, brainstem, and cerebellar regions and hypoactivity in parietal and cingulate gyrus were found in the patients who later developed TD in contrast to those who did not. The groups were matched on clinical measures and had similar neuropsychological and neuroanatomic testing results. Thus, differences in the metabolic activity of specific brain regions are associated with vulnerability to TD development.

Proactive inhibition and semantic organization: relationship with verbal memory in patients with schizophrenia

Compared to other cognitive functions in schizophrenia, evidence suggests that verbal memory is particularly impaired. This study used the California Verbal Learning Test (CVLT) to examine proactive inhibition (PI) and semantic processing in verbal memory in 29 patients with schizophrenia and 29 healthy controls. Patients showed significantly less PI, but also did not organize (cluster) their recall according to semantic category. Controls and patients demonstrated small retroactive inhibition (RI) effects regardless of semantic content. Although both groups made similar types and numbers of free recall intrusion errors patients committed more phonemic and nonshared recognition errors. Results suggest that reduced semantic processing prevented build of PI, and contributes to defective memory in schizophrenia. The anatomic-physiologic abnormalities that underlie these findings may be particularly pronounced in prefrontal and temporal-parietal cortical areas.

Effect of the combination of cisplatinum and radiation in the rabbit's brain

The effect of cisplatinum as a potential radiosensitizer in brain tumors is controversial. We examined the effect of the combination of cisplatinum with radiation compared to radiation alone in rabbits' brain. All rabbits were irradiated and cisplatinum was injected intravenously into part of them. Therapeutic doses of cisplatinum and irradiation were given. The rabbits were euthanised at different intervals according to protocol. The general clinical and neurological condition of the rabbits was unaffected, and histopathological examination of the rabbit's brain was normal. The purpose of this study was to establish the effect of cisplatinum followed by cranial irradiation in therapeutic doses to the normal rabbit's brain.

Relationships between verbal memory performance and the cerebral distribution of fluorodeoxyglucose in patients with schizophrenia

Quantitative resting fluorodeoxyglucose-positron emission tomography scans were performed on 42 patients with schizophrenia. Magnetic resonance imaging-based regions of interest were transposed onto the corresponding positron emission tomography images. Region to whole brain ratios were calculated from the mean regional activity per pixel across both hemispheres (left plus right). Laterality scores were calculated from the difference between the mean activity in homotopic regions of the two hemispheres (left minus right). Subjects were tested contemporaneously with the Logical Memory subtest of the Wechsler Memory Scale. The subtest was scored with modified criteria to provide information about verbal recall, perseverations, and other components of verbal memory. Deficits in recall were associated with increased metabolism in selected regions of the left hemisphere that are known to mediate aspects of verbal memory. The findings support hypotheses suggesting that the left hemisphere is functionally overactive in schizophrenia.

Schizophrenia throughout life: sex differences in severity and profile of symptoms

BACKGROUND

The impact of aging and of gender has been examined in health and disease, but has received limited attention in schizophrenia. A lifespan perspective of gender differences can contribute to an understanding of clinical features and their underlying neurobiological processes.

METHOD

A prospective sample of 272 patients with schizophrenia, divided into four age groups: < 35, 35-65, 65-80 and > 85, was assessed with standardized procedures to measure the composition and severity of symptoms.

RESULTS

Aging was associated with increased severity of symptoms and gender differences were noted. Negative symptoms increased in severity, while some positive symptoms ameliorated with aging. Women were characterized by reduced negative symptoms, and this remained evident until the eighth decade.

CONCLUSIONS

Aging and gender moderate the clinical features of schizophrenia in specific symptom clusters. These effects may give insight into neurobiological substrates of the illness.

Sex differences in neuroanatomical and clinical correlations in schizophrenia

OBJECTIVE

The purpose of this study was to investigate sex differences in relationships between brain and behavior in schizophrenia.

METHOD

Frontal lobe, temporal lobe, and whole brain volumes were obtained from magnetic resonance images of 91 patients with schizophrenia (54 men and 37 women) and 114 healthy comparison subjects (62 men and 52 women). Four independent symptom scales, based on the following symptom clusters, were derived from clinical data: negative, disorganization, Schneiderian hallucinations-delusions, and suspicion-hostility. Regression analyses incorporating the four clinical scales and neuroanatomical volumes were performed to investigate possible interactions between brain region and sex.

RESULTS

Significant interactive effects of sex and frontal lobe volume were found in regression analyses of the disorganization and suspicion-hostility symptom scales. In men, higher frontal lobe volume was associated with milder severity of disorganization but was not correlated with severity of suspicion-hostility. In women, higher frontal lobe volume was associated with more severe disorganization as well as more severe suspicion-hostility. No associations were found between brain volume and severity of negative or Schneiderian symptoms.

CONCLUSIONS

Differences between male and female patients were observed in the relationships between frontal lobe volume and two of the four clinical dimensions examined. These findings suggest that aspects of the neuropathological basis for some symptoms of schizophrenia may be sexually dimorphic.

Age associated decrements in dopamine D2 receptors in thalamus and in temporal insula of human subjects

This study evaluates the effects of age on DA D2 receptors in extrastriatal regions. DA D2 receptor availability was evaluated in 42 healthy male subjects (mean age 41 +/- 16, range 21 - 86 year old) with positron emission tomography (PET) and [11C]raclopride. Estimates of Bmax/Kd were obtained using the ratio of the distribution volume in the region of interest (caudate, putamen, thalamus, frontal, occipital cortices, temporal insula, cingulate and orbitofrontal gyri) to that in cerebellum. Correlations between age and D2 receptors were significant in putamen (r = -0.58, p < or = 0.0001), caudate (r = -0.54, p < or = 0.0002), thalamus (r = -0.33, p < or = 0.03) and temporal insula (r = -0.39, p < or = 0.01) but not in any of the frontal regions. The decrease in DA D2 receptor availability was 6.6% per decade in caudate, 8.2% in putamen, 7.6% in thalamus and 13% in temporal insula. This study indicates that D2 losses with age are not limited to striatum and involve also thalamic as well as temporal cortical regions.

Dopamine transporters decrease with age

Postmortem studies have documented degeneration of dopamine cells with age, but the changes that occur in healthy aging individuals is less clear. The purpose of this study was to evaluate the extent to which age-induced changes in dopamine transporters occur in subjects with no evidence of motor impairment.

METHODS

We evaluated 23 right-handed healthy volunteers (age range 20-74 yr) using PET and [11C]d-threo-methylphenidate. The ratio of the distribution volume for [11C]d-threo-methylphenidate in striatum to that in cerebellum was used as model parameter for dopamine transporter availability (Bmax/Kd + 1).

RESULTS

Dopamine transporter availability was significantly lower in subjects > 40 yr of age than in those < 40 yr. Estimates of dopamine transporter availability showed a significant negative correlation with age both for the putamen (r = -0.72, p < 0.0001) and the caudate (r = -0.74, p < 0.0001). Dopamine transporter availability was higher in the left than in the right putamen but did not differ between the left and right caudate.

CONCLUSION

This study documents a 6.6% decrease per decade of life in striatal dopamine transporters of healthy volunteers.

Cerebral blood flow changes in limbic regions induced by unsolvable anagram tasks

OBJECTIVE

The study addressed the question of whether unsolvable as opposed to solvable cognitive problems activate discrete neuronal systems in the human brain.

METHOD

Twelve healthy humans tried to solve unsolvable anagrams. Solvable anagrams and a resting baseline after each anagram task served as control conditions in a within-subject design. Activation was measured with the equilibrium infusion method by using 15O-labeled water and positron emission tomography, with absolute quantitation of anatomically defined regional cerebral blood flow (CBF).

RESULTS

Compared to rest, both anagram tasks increased activity in frontal and temporal regions. The soluble task condition increased hippocampal activation and decreased mammillary bodies activity, while unsolvable anagrams were associated with increased CBF to the mamillary bodies and amygdala and decreased hippocampal activity.

CONCLUSIONS

A limbic network integrating negative emotion and cognition seems reflected in reciprocal diencephalic and limbic activation with solvable and unsolvable anagrams. Since unsolvable anagrams have been used to induce learned helplessness in humans, this finding may provide an initial step toward clarifying its neural substrate.

Frontal and temporal lobe brain volumes in schizophrenia. Relationship to symptoms and clinical subtype

BACKGROUND

Quantitative magnetic resonance imaging (MRI) studies demonstrate reduced brain volumes in schizophrenics, but specific structural abnormalities have not been clearly delineated. The structural abnormalities of this disorder are likely to be heterogeneous, consistent with its diverse clinical presentation. To investigate the relationship between structural abnormality and clinical symptoms, we examined regional brain and cerebral spinal fluid (CSF) volumes in a large sample of schizophrenic patients and controls, with patients aggregated into clinical subtypes.

METHODS

Right and left hemisphere frontal and temporal lobe brain and CSF volumes were quantified from 5-mm axial spin-echo MRIs for 71 schizophrenic patients and 77 age- and sex-matched controls. The following four standardized rating scales were used to assess symptom severity: Negative Symptoms, Disorganization, Schneiderian Delusions and Hallucinations, and Suspicion-Hostility. Patients were also subtyped as either deficit or nondeficit on the basis of enduring negative symptoms.

RESULTS

Schizophrenic patients overall exhibited abnormal brain asymmetry, with selective decrease in brain volume in the left temporal and right frontal regions. Left temporal lobe parenchymal volume reduction and CSF volume increase were correlated with the severity of negative symptoms. Consistent with this, the subtype analysis revealed abnormal temporal lobe asymmetry for the deficit subgroup only. Right frontal lobe volume reduction correlated with the duration of illness, independent of symptom severity or schizophrenic subtype.

CONCLUSIONS

Abnormal lateral asymmetry suggests selective structural deficits in schizophrenia, rather than diffusely undifferentiated CNS abnormalities. The pattern of regional abnormalities is related to clinical symptoms, with negative symptoms being associated with left temporal lobe rather than frontal lobe abnormality. This is consistent with suggestions of a temporolimbic prefrontal network abnormality in schizophrenia. Further longitudinal studies are warranted, using higher-resolution MRI technology and gray matter-white matter segmentation to confirm and extend these findings.

Mood effects on limbic blood flow correlate with emotional self-rating: a PET study with oxygen-15 labeled water

Positron emission tomography was used to study the effects of experimentally controlled mood states on cerebral blood flow (CBF), measured with the quantitative equilibrium infusion method and 15O-labeled water. Twenty-seven brain regions in each hemisphere were assessed in 16 normal subjects. CBF and heart rate were measured during happy and sad mood induction, and during two nonemotional control conditions: sex differentiation and resting baseline. Valence-specific effects of mood on CBF were obtained for subcortical, but not for frontal-temporal or control regions. CBF increased in left amygdala and decreased in right amygdala during sad mood relative to the averaged control conditions. These changes correlated with shifts toward negative affect. Correlations were opposite for subcortical (negative affect associated with lower left hemispheric CBF) compared with frontal-temporal cortical regions. Results support limbic involvement in regulating emotional states and suggest some reciprocity between subcortical and frontal-temporal regulation of emotional experience.

Language before and after temporal lobectomy: specificity of acute changes and relation to early risk factors

We evaluated language functions in 154 patients with left hemisphere speech dominance undergoing anterior temporal lobectomy (ATL). Measures of phonemic and semantic fluency, confrontation naming, repetition, comprehension, and reading were administered before and 3 weeks postoperatively. Patients were grouped by focus (left, LT; right, RT) and presence of early risk factors for development of seizures (ER, early risk, < or = 5 years; NER, no early risk): (LT-ER, n = 45; RT-ER, n = 49; LT-NER, n = 27; RT-NER, n = 33). Preoperatively, the LT group showed a selective naming deficit as compared with the RT group. Postoperatively only the LT-NER group showed significant overall decline in language. For this group, the change was attributable to a selective decline in naming as compared with other functions. These data indicate that there is a specific risk to naming after dominant ATL for adult temporal lobe epilepsy (TLE) patients with a left hemisphere focus and the absence of an early risk factor for the development of seizures.

Emotional processing in schizophrenia: neurobehavioral probes in relation to psychopathology

The application of neurobehavioral methods in functional neuroimaging can provide useful information on the neurobiology of schizophrenia. This process can be enhanced by using a standard set of procedures to construct 'neurobehavioral probes' which are suitable for functional imaging and provide reliable measures discriminating patients from healthy controls. While such probes are available for cognitive tasks, none has been applied to study emotional processing in schizophrenia. We examined emotional discrimination and experience probes and correlated performance with cognitive and clinical measures. Emotion discrimination tasks and mood induction procedures with happy, sad, and neutral facial expressions were administered to 40 patients with schizophrenia. Neuropsychological testing assessed intellectual, attention, abstraction-flexibility, memory, language, spatial, and sensory-motor functions. Emotional performance was compared to a group of 40 normal subjects. Performance for face discrimination was impaired in patients. There was specific impairment in discrimination of happy expressions. Mood induction was effective in both groups, but diminished in patients, especially for happiness. Poorer performance in emotion discrimination correlated with severity of negative symptoms and bizarre behavior. Hallucinations were associated with more pronounced mood induction effects. Emotion discrimination was also correlated with abstraction, memory, language and spatial tasks, while mood induction effects showed no such associations. Thus, the impairment in discriminating and experiencing valence-specific emotions in schizophrenia relates to symptomatology and neuropsychological functioning. The results encourage the use of the emotion discrimination task and the mood induction procedure as neurobehavioral probes in physiologic neuroimaging studies for investigating the neural substrates of emotion.

Prospective clinicopathologic studies of schizophrenia: accrual and assessment of patients

OBJECTIVE

The purpose of this study was to characterize the neuropsychiatric profile of elderly patients with schizophrenia and establish a patient registry for prospective ante-mortem and post-mortem studies.

METHOD

Medical records of all chronically institutionalized patients in eight state hospitals who were over the age of 65 and had a chart diagnosis of schizophrenia (N = 528) were reviewed. Of the potential subjects, 192 were excluded because of clinical histories inconsistent with a diagnosis of schizophrenia, 56 because of insufficient information to establish a psychiatric diagnosis, and 122 because of family members' refusal to give consent for autopsy in the event of death. To date, 81 of the remaining 158 patients have undergone neuropsychiatric evaluation with standard assessment instruments.

RESULTS

Mini-Mental State scores of the 81 patients indicated severe dementia, and Functional Assessment Scale scores showed that patients required assistance with activities of daily living. All patients were rated as severely ill on the Brief Psychiatric Rating Scale. Ratings on the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms indicated a predominance of negative symptoms over positive. Of 30 patients who have died to date, research autopsies have been conducted on 26.

CONCLUSIONS

Establishing a well characterized, prospective patient registry for clinicopathologic studies of schizophrenia is feasible but labor intensive. Diagnosis of schizophrenia with a high degree of confidence can be achieved by means of detailed chart review and assessment of current neuropsychiatric functioning with standard rating instruments. These data provide a basis for correlations of clinicopathologic factors.

Smaller neuron size in schizophrenia in hippocampal subfields that mediate cortical-hippocampal interactions

OBJECTIVE

The goal of this study was to characterize the hippocampal formation in patients with schizophrenia by measuring neuron density, neuron size, and variability of neuronal axis orientation.

METHOD

Brain tissue was obtained at autopsy from 14 prospectively accrued elderly patients with chronic schizophrenia and 10 age-compatible individuals without psychiatric disorder. Eight hippocampal regions of interest and two internal control regions (primary motor and visual cortices) were identified on Nissl-stained sections. Morphometric measurements were made without knowledge of diagnosis by means of a computer-based image analysis system.

RESULTS

The patients exhibited smaller neuron size in the hippocampal regions relative to the control regions, which was significant only for the subiculum, CA1, and layer II of the entorhinal cortex. Neuron size in the control regions was nearly identical in the two groups. No significant differences in neuron density or in variability of neuronal axis orientation were identified for any region. There was no correlation between neuron size in any area and several potentially confounding variables (age, post-mortem interval, neuroleptic exposure, sex, brain hemisphere studied, duration of illness), with the exception of a negative correlation with age in layer II of the entorhinal cortex. Regression analyses indicated that the findings could not be attributed to these age effects.

CONCLUSIONS

The subiculum, entorhinal cortex, and CA1 are the major subfields of the hippocampal region that maintain the afferent and efferent connections of the hippocampus with widespread cortical and subcortical targets. The smaller size of neurons in these subfields may reflect the presence of structural or functional impairments that disrupt these connections, which in turn could have important behavioral sequelae.

Reading on the Wide Range Achievement Test-Revised and parental education as predictors of IQ: comparison with the Barona formula

It is frequently necessary in research and clinical evaluations to obtain estimates of premorbid intelligence (IQ) which are separate from measured IQ. There is evidence that word reading may be useful in this aim. In order to determine the potential of the Wide Range Achievement Test-Revised (WRAT-R) reading subtest (READ) as an estimate of premorbid IQ, the present study examined the relationship between READ and IQ in healthy subjects. Consistent with other findings, READ accounted for a significant amount of variance in Verbal, Performance, and Full Scale IQ. Race and parental education, the latter being a variable not previously examined in this literature, accounted for incrementally valid variance in IQ beyond READ. The predictive power of these variables compares favorably with estimates made by the Barona IQ estimation formula, which uses only demographic information.

Evaluation of age-related changes in serotonin 5-HT2 and dopamine D2 receptor availability in healthy human subjects

We assessed the relation between serotonin 5-HT2 receptor availability and aging and compared it with that for dopamine D2 receptors on 19 healthy male volunteers (age range, 21-49 years) using positron emission tomography (PET) and F-18 N-methylspiperone (NMS). 5-HT2 Receptor availability was obtained using the ratio of the distribution volume in the region of interest to that in the cerebellum (Bmax'/Kd' + 1). 5-HT2 Receptor measures were obtained in frontal and occipital cortices. D2 receptor availability in striatum was measured using the "ratio index". 5-HT2 Receptor availability decreased significantly with age. This effect was significantly more accentuated for 5-HT2 receptor availability in the frontal (r = 0.92, p < or = 0.0001) than in the occipital (r = 0.67, p < or = 0.0016) cortex (df = 1, p < 0.025). Dopamine D2 receptors were also found to decrease significantly with age (r = 0.63, p < or = 0.007). In a given subject, striatal D2 receptor availability significantly correlated with 5-HT2 receptor availability in the frontal (r = 0.51, p < or = 0.035) but not in the occipital cortex. These results document a decline in 5-HT2 and D2 receptor availability with age and showed an association between frontal 5-HT2 and striatal D2 receptors.

Sex differences in regional cerebral glucose metabolism during a resting state

Positron emission tomography was used to evaluate the regional distribution of cerebral glucose metabolism in 61 healthy adults at rest. Although the profile of metabolic activity was similar for men and women, some sex differences and hemispheric asymmetries were detectable. Men had relatively higher metabolism than women in temporal-limbic regions and cerebellum and relatively lower metabolism in cingulate regions. In both sexes, metabolism was relatively higher in left association cortices and the cingulate region and in right ventro-temporal limbic regions and their projections. These results are consistent with the hypothesis that differences in cognitive and emotional processing have biological substrates.

The stability of tachistoscopic measures of hemispheric specialization

Two-week test-retest reliabilities were determined for two tachistoscopic tasks, consonant-vowel-consonant trigrams and dot location, in 48 right-handed university students. Both visual field and laterality scores were examined. Analysis of variance showed no significant main effects or interactions of session for either task, indicating stability of mean performance and laterality scores. Likewise, grouping subjects as "high" or "low" by median laterality scores showed concordance across sessions for both tasks. Test-retest correlations were moderately high for all verbal task measures and for visual field scores for the dot location test. However, laterality indices for dot location showed low stability despite comparable within-session reliabilities of laterality scores for the two tasks. These findings suggest stability of group means and subgroups for verbal and dot location tachistoscopic measures. However, the degree to which individual scores are predictable from one session to the next differs between the two tasks.

MMPI characteristics in adults diagnosed with ADD: a preliminary report

Characterization of Attention Deficit Disorder (ADD) in adults has been hampered by an absence of well-defined clinical profiles on objective personality measures. A sample of 22 ADD adults completed personality testing (MMPI) in conjunction with cognitive assessment. A sample of 30 normal controls and 20 patients diagnosed with schizophrenia, who had completed the MMPI as part of a larger research protocol, were utilized as comparison groups. Validity and clinical scales revealed multiple elevations in the ADD group which were similar in nature but not to the same degree as elevations observed in the schizophrenia group. Harris-Lingoes subscales identified the sources of clinical scale elevations indicating a pattern of specific and nonspecific symptomatology which differentiated the three groups. The results may aid in identifying ADD in adults.

Neuropsychological functioning in siblings discordant for schizophrenia and healthy volunteers

OBJECTIVE

To determine whether schizophrenics and their nonschizophrenic siblings have a similar pattern of neuropsychological deficit when compared with normal controls.

DESIGN AND PARTICIPANTS

Fifteen probands with schizophrenia, 16 of their nonschizophrenic siblings, and 31 unrelated, demographically balanced, normal individuals underwent evaluation with a comprehensive neuropsychological test battery. All subjects were screened for history of head injury, neurologic illness, major medical conditions, substance use, and axis I psychiatric disorders other than schizophrenia. Probands underwent evaluation twice: once at intake when half had never received neuroleptic medication and the other half had received none for a minimum of 2 weeks, and again at the 2- to 4-week follow-up, after stabilization with neuroleptic medications.

RESULTS

Both schizophrenics and their nonschizophrenic siblings were impaired neuropsychologically compared with normal controls, with the nonschizophrenic siblings' performance intermediate between that of the schizophrenic siblings and the normal controls on all measures of functioning. The shapes of the deficit profiles of schizophrenic patients and their siblings were similar; in patients, verbal memory, abstraction, attention, and language functions were significantly more affected compared with spatial abilities, spatial memory, and sensory-motor functions, with a nonsignificant trend in the same direction in siblings. Cognitive functioning in patients was found to be stable across changes in medication status and clinical state. Four fifths of patients obtained more deviant scores than their nonschizophrenic siblings. Among the sibling group, those with probable and certain diagnoses of schizotypal personality disorder were more impaired compared with those without schizophrenia-spectrum symptoms.

CONCLUSION

These results support the hypothesis that impaired information processing aggregates in the family members of schizophrenics and may serve as an indicator of genetic vulnerability to the disorder. Further work is needed to establish whether particular areas of functioning are selectively impaired in relatives and to determine whether the performance deficits are mediated by structural and/or metabolic disturbances in specific brain regions.

Sex differences in aging of the human frontal and temporal lobes

This study investigated effects of age and sex on regional brain structure in humans, focusing on the frontal and temporal lobes. Hemispheric volumes were obtained from magnetic resonance images (MRIs) of 96 young (53 men, 43 women; aged 18-40 years) and 34 older (17 men, 17 women; aged 41-80) healthy volunteers. Images (5 mm axial spin-echo, repetition time of 3000 msec and echo times of 30 and 80 msec) were resliced along the anterior commissure-posterior commissure (AC-PC) axis to standardize for difference in head tilt, and imported into a computer program where borders of the frontal and temporal lobes were delineated. The program calculated regional brain volumes based on slice data from which CSF was segmented out. An age x sex x hemisphere x region interaction indicated that age-related reductions in brain volume were sexually dimorphic, lateralized, and region specific. Greater decrements in brain volume occurred with age in the frontal lobe than in the temporal lobe. Age-related reductions in both regions were greater in men than in women, demonstrating that sexual dimorphisms in human neuroanatomy are not fixed, but continue to change throughout adulthood. The possibility that gonadal hormones play a role in the promotion and/or prevention of neural atrophy with aging is discussed.