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Objective: This initial report, from an ongoing study, examines whether children who have symptoms of schizophrenia spectrum disorder display neuropsychological or neuroanatomic abnormalities similar to those seen in adults with schizophrenia., Method: Experimental subjects were 12 children between 8 and 12 years of age who displayed symptoms of early-onset schizophrenia or schizotypal personality disorder, as assessed through the Schedule for Affective Disorders and Schizophrenia for School-Age Children. The experimental subjects were compared with 13 controls on neuropsychological test performance, magnetic resonance imaging measurements, and proton magnetic resonance spectroscopy results., Results: Findings from the first phase of this project reveal significant overall group differences for several morphometric magnetic resonance imaging measurements and all neuropsychological measures. Differences between the groups were found for amygdala volume, mesial temporal volume, callosal area, and anatomic asymmetry. Magnetic resonance spectroscopy data showed a trend toward group differences., Conclusions: These findings support a neurodevelopmental model of schizophrenia which postulates that environmentally or genetically programmed events in utero disrupt the establishment of fundamental aspects of brain structure and function.

The present study investigated lateralization of perceptual closure ability. A zero-power, partially occluded, soft contact-lens system was used to lateralize visual input. This technique has been shown to create reliable artificial visual-field deficits when used in situations offering unlimited duration of stimulus exposure. The Street Gestalt Completion Test was administered to 18 right-handed men with no history of head trauma, neurological disorders, or familial sinistrality. Using repeated-measures analyses, and controlling for age, we found no significant hemispheric advantage for either speed or accuracy of performance.

Total tumor cathepsin D (TCD) levels were determined prospectively by a radioimmunometric assay in tumor cytosol of 858 primary breast cancer patients diagnosed between 1989-1991. In 581 of these patients, tumor HER-2/neu oncogene amplification was simultaneously determined. In a "training-set" of 313 patients, "high" TCD was associated with significantly shorter disease-free survival (DFS). For the whole group, there was no correlation between TCD and pathologic stage, number of axillary nodes with tumor deposits, tumor size, histologic type and grade, or hormone receptor levels. In the node-positive group, high TCD level was associated with HER-2/neu amplification. After a median follow-up duration of 31 months, univariate analysis indicated that high TCD level was significantly associated with shorter DFS only in node-positive patients. The shorter DFS in association with high TCD levels was observed in both estrogen-receptor-positive and -negative patients. Cox multivariate analysis of DFS confirmed that high TCD level was predictive of shorter DFS in node-positive patients only. Because of the short duration of follow-up, the significance of TCD in overall survival was not determined. We conclude that high tumor TCD in node-positive patients is predictive of shorter DFS, and is often associated with HER-2/neu amplification. The possibility exists that high tumor TCD may act in combination with HER-2/neu amplification to promote dissemination of metastases.

Rosenstein and Bigler reported in 1987 that sexual orientation (exclusively versus nonexclusively heterosexual) was not related to right- versus nonright-handedness. However, re-analysis of their published data indicated that nonexclusive heterosexuals were 3.13 times more likely to be nonright-handed than were exclusively heterosexual subjects (p < .03).

Individual variations in anatomic cerebral asymmetries have been linked with specific neurodevelopmental processes, with patterns of cognitive ability, and with recovery from focal brain damage. The present study investigated relationships between cerebral asymmetries and recovery from aphasia. Aphasic patients (N = 25) were assessed for language recovery for 1 year poststroke, and linear measurements of cerebral asymmetries were performed on CT scans. Increasing left occipital width asymmetry was associated with faster rate of language recovery and with higher final language scores during the first year poststroke. There was, moreover, a tendency for increasing left occipital width asymmetry to be associated with less initial impairment. It is hypothesized that those aspects of neural organization conferring better premorbid language skills are the same factors conferring greater recovery of language skills and that occipital width asymmetry serves as a marker for such individual differences in neural organization.

This study utilized a unique contact lens method to examine the influence of right hemisphere processing on affective judgments and pain perception. Under conditions of unilateral visual stimulation, participants completed affective ratings of films and underwent a cold pressor pain task. The goal was to examine differences in affective judgments of films projected to one or the other hemisphere and to examine the influence of this unilateral visual stimulation on pain sensitivity. The results failed to replicate a previous finding of differential affective judgments under conditions of right and left visual stimulation. Nonetheless, in female subjects, unilateral visual stimulation was significantly associated with pain lateralization. This finding is discussed in terms of attentional processes in pain perception and limitations of the current lens design.

A soft contact-lens system for achieving unilateral visual stimulation in a free vision format is described. Initial testing with light transmittance and visual perimetry indicated that the lenses created artificial visual-field deficits. The efficacy of the lenses as a technique for lateralizing visual input was evaluated by examining within-subject differences in performance on two visuospatial tasks. Speed and accuracy of performance were greater with visual input directed to the right hemisphere. These data support the lens design as a useful alternative to tachistoscopic procedures and previous lens systems.

The purpose of this study was to determine the relationship between hearing status and cognitive status initially and at 5-year follow-up in a cohort of healthy elderly men and women and to relate the results to published reports on this topic. Volunteers older than 60 years with no major illnesses and taking no long-term prescription medications were examined. Baseline testing of hearing and cognition was performed in 224 subjects; 112 subjects underwent cognitive testing at 5-year follow-up. Hearing was measured by the Speech Perception in Noise test; cognition was measured by two parts of the Wechsler Memory Scale and by the Jacobs Cognitive Screening Test, an oral screening instrument. At baseline there were small correlations between hearing acuity and memory scores, but these disappeared after adjustment for age and gender. Analysis of follow-up memory and cognitive screening test scores in relation to baseline hearing ability showed no correlation between hearing at entry and cognitive function at 5 years. In addition, baseline hearing level did not predict change in memory or cognitive screening test scores during the follow-up period. The power of the study was 90% to detect a correlation of .30 between measures of hearing and cognition. There was no evidence for a major effect of hearing acuity on cognitive function over time in this group of healthy elderly. Review of published studies suggests that hearing ability is related to cognitive status in demented subjects, but there is little to suggest that in the normal elderly, hearing impairment leads to cognitive decline.

Studies of localization of brain function in humans depend on analysis of covariation between the location of naturally occurring lesions and measures of neuropsychological ability. Such an analysis presents two problems: how to represent numerically the infinite variety of lesion locations, sizes, and shapes; and how to assess covariation between the location measure and performance. We present a mathematical model of lesion location and its relationship with performance. To demonstrate its utility, the model is applied to a sample of 53 patients with naturally occurring brain lesions who were administered a standard battery of neuropsychological tests. Importance functions derived for the neuropsychological measures generally conform to expectations. Sensory and motor abilities were localized correctly within the contralateral hemispheres, and language functions were localized in the left frontal region. Lesion location accounts for substantially more variation in performance than does lesion volume, with location accounting for more than 50% for some left-hemisphere functions.

The sequence of the P (phosphoprotein) gene of mumps virus has been determined. It has two open reading frames, the first of which probably encodes the NS1 (or V) protein of mumps virus. Expression of the P protein requires the insertion of two non-templated residues to link the two ORFs in a process analogous to that observed in the P/V gene of simian virus type 5 to which mumps virus is closely related. Strain differences in the accuracy of insertion of non-templated G residues in the P/V gene transcripts have been described.

A current model proposes that memory consists of two functionally separate systems that have different neurological substrates. Declarative memory appears to be dependent on the diencephalic medial temporal lobe system whereas some speculate that the basal ganglia may be a neurological substrate for procedural memory. This study tested the role of the basal ganglia in regulating different types of procedural skills by comparing performance on a motor and a visuoperceptual skill learning task. Twenty Parkinson's (PD) patients and 20 normal control subjects performed two procedural learning tasks (rotary pursuit and mirror reading) and one declarative learning task (paired associates) over 3 days. The results showed that PD patients were not impaired on mirror reading or paired associate learning. On rotary pursuit, performance levels on day 1 were similar between groups, but the PD group showed less improvement across days than controls. However, only patients with more advanced symptoms of PD showed impaired rotary pursuit learning, and this could not be attributed directly to deficits in primary motor or general cognitive function. These findings suggest that the underlying processes/procedures for procedural learning are specific to the task, and are supported by different neuroanatomical systems.

Although it is widely accepted that lesion size is an important determinant of severity of deficit, difficulties in the quantification of lesion size and the absence of a theoretical model of how lesion volume combines with lesion locus to produce deficits have inhibited the development of methodological and statistical procedures for studying naturally occurring lesions in humans. We propose such a unified model and apply it to the analysis of neuropsychological performance in a sample of patients with naturally occurring unilateral lesions. The analysis suggests that a statistical interaction between lesion size and laterality may be an important determinant of neuropsychological deficit.

During a 3-year period Branhamella catarrhalis was isolated in significant numbers from 239 (1.3%) of 19,488 specimens of sputum sent for routine microbiological examination at a 700-bed general hospital. The majority of patients (83%) were over 60 years of age and 65% were male. There was a distinct seasonal variation in isolations with a peak incidence during the winter and early spring, a pattern not found with other pathogens. Susceptibility to amoxycillin decreased by approximately 50% over the 3 years, corresponding to an increased incidence of beta-lactamase-producing strains. There were minimal changes in susceptibility to other antimicrobial agents. Underlying pulmonary disease was the major factor predisposing to B. catarrhalis infection, and 71% of patients were smokers or ex-smokers.

In this study we investigated the association between morphological asymmetry and patterns of cognitive ability in dementia of Alzheimer's type (DAT). Digitized CT scans were used to estimate volumetric parameters of the brain. The volume of the cranium, brain parenchyma, the subarachnoid space, and lateral ventricles was computed. The volume of the subarachnoid space was used as an index of cortical atrophy, while the ventricular volume served as an estimate of subcortical atrophy. Asymmetry indices were computed for all structures as the difference between left and right volume divided by their average and multiplied by 100. Cognitive asymmetry index was computed by dividing the difference between VIQ and PIQ of the Wechsler Adult Intelligence Scale (WAIS) by their average and multiplying by 100. After statistically controlling for cranial asymmetry, hemispheric asymmetry was found to correlate positively with cognitive asymmetry. The correlation was somewhat greater for male than for female patients. Asymmetry of both cortical and subcortical atrophy correlated negatively with cognitive asymmetry.

The performance of right-handed males and females, with and without a family history of sinistrality (FS+ and FS-, respectively) were examined for three cognitive abilities: spatial ability, verbal fluency, and perceptual speed. FS+ subjects, especially females, showed performance decrements in spatial ability. Also, FS+ subjects, especially males, showed performance decrements in perceptual speed, with no differences being observed in verbal fluency.

The clinical relevance of white matter hyperintensities (WMH) seen on MRIs of elderly individuals is controversial. To resolve this issue, we performed MRI and neuropsychological testing on 46 healthy participants in the longitudinal Aging Process Study at the University of New Mexico. We graded the MRIs for severity of WMH using a scale tested on an elderly patient population. We found that 22% of normal subjects had moderate lesions and 9% had severe lesions. All subjects had normal neurologic examination findings and were within normal limits on a battery of neuropsychological tests. Neuropsychological performance decreased and the severity of WMH increased with age. However, when the data were corrected for age, there was no correlation between neuropsychological function and the presence of WMH. We conclude that white matter changes in the elderly by themselves are of doubtful clinical significance.

Volumetric measures of the brain and ventricles were derived from CT films and related to intellectual variables from the Wechsler Adult Intelligence Scale (WAIS). Subjects were patients referred for neurological examination for headache or somatic complaints, sometimes accompanied by anxiety or dysphoric affect (N = 41), for whom a comprehensive neurological work-up revealed no evidence of abnormality. The asymmetry of hemispheric volume (left minus right over total, times 100) was correlated (r = .57, p less than .001) with Verbal IQ minus Performance IQ within subjects. No relationship was observed between total brain or hemispheric volumes and IQ scores. Brain and ventricular volumes were larger for the left hemisphere than the right.

The present study attempts to delineate the role of hemispheric activation in depression and pain. It was hypothesized that the right hemisphere is specialized to become activated by and to process negative affective stimuli, and that this specialization may play a role in the co-occurrence of depression and pain. The relationship between depression, experimental pain, and cerebral laterality was investigated in 16 depressed and 16 nondepressed, right-handed, female students. Cerebral laterality was measured via tasks assessing visual and auditory biases, and pain was assessed via a cold pressor task. The proposition that the right hemisphere mediates the co-occurrence of pain and depression was not supported, but specific findings did suggest that the right hemisphere may play a unique role in pain perception. Data from the visual task indicated that prior exposure to pain results in increased right hemisphere activation as indicated by a left visual field bias. Pain perception was a complex function of mood, preceding tasks, and the hand tested, and it was suggested that exposure to a typical right-hemisphere task increased the left side lateralization of pain in nondepressed subjects. Implications of these findings are discussed for coexisting problems of pain and depression and for the lateralization of pain in disorders judged to involve a significant psychogenic component.

Most of the methods of quantifying cortical atrophy that have been proposed involve the estimation of the volume of enlarged sulci in the cerebral cortex. The authors propose that the surface area of the sulci is a more valid measure of cortical atrophy, and describe a system for measuring the surface area of the cortex, and present data in support of the method's reliability and validity.

The effects of task complexity on movement ipsilateral to lesion were examined using the Fitts tapping task [Fitts, P.M., J. exp. Psychol. 47, 381-391, 1954]. Subjects were required to rapidly tap two targets, which were 1 or 4 cm wide. Twenty controls and ten left hemisphere and nine right hemisphere stroke patients were studied. Only the left hemisphere group showed significant deficits with greater impairment found in the wide target condition. Quantified CT scan analyses indicated lesion volume was similar between CVA groups, but the left hemisphere group's lesions were more anterior. The results are discussed in terms of inter- and intrahemispheric roles in open and closed loop movements.

Several lines of inquiry provide converging evidence for a critical role for the right cerebral hemisphere in negative affective experiences. This research includes the assessment of affective consequences of both focal cerebral lesions and pharmacological inactivation of one or the other hemisphere, as well as experimental and physiological techniques assessing differential hemispheric activation. The specific nature of right hemispheric involvement is conceptualized as a tendency to become activated by aversive experiences, and once activated, to process stimuli in a manner consistent with the right hemisphere's more negative affective tone. A theory of right hemisphere involvement in depressive affect is presented in detail and its relevance to clinical phenomena, e.g., the co-occurrence of depression and pain, and sex differences in depression, is examined, as is congruence with cognitive theories of depression.

Of a consecutive series of 25 patients with peritonitis secondary to colonic diverticular disease all, except one with faecal peritonitis, underwent some form of emergency resection.All the three patients with faecal peritonitis died, but the 22 with purulent peritonitis survived. The average duration of the emergency admission of the 22 survivors was 25.4 days, and in nine (41%) of them intestinal continuity had been restored by the end of that admission.Thus some form of emergency resection is the operation of choice in patients with spreading peritonitis due to diverticular disease of the sigmoid colon.