Charlie L. Swanson

An fMRI study of sex differences in regional activation to a verbal and a spatial task.

Sex differences in cognitive performance have been documented, women performing better on some phonological tasks and men on spatial tasks. An earlier fMRI study suggested sex differences in distributed brain activation during phonological processing, with bilateral activation seen in women while men showed primarily left-lateralized activation. This blood oxygen level-dependent fMRI study examined sex differences (14 men, 13 women) in activation for a spatial task (judgment of line orientation) compared to a verbal-reasoning task (analogies) that does not typically show sex differences. Task difficulty was manipulated. Hypothesized ROI-based analysis documented the expected left-lateralized changes for the verbal task in the inferior parietal and planum temporal regions in both men and women, but only men showed right-lateralized increase for the spatial task in these regions. Image-based analysis revealed a distributed network of cortical regions activated by the tasks, which consisted of the lateral frontal, medial frontal, mid-temporal, occipitoparietal, and occipital regions. The activation was more left lateralized for the verbal and more right for the spatial tasks, but men also showed some left activation for the spatial task, which was not seen in women. Increased task difficulty produced more distributed activation for the verbal and more circumscribed activation for the spatial task. The results suggest that failure to activate the appropriate hemisphere in regions directly involved in task performance may explain certain sex differences in performance. They also extend, for a spatial task, the principle that bilateral activation in a distributed cognitive system underlies sex differences in performance.

Depression in schizophrenia: I. association with neuropsychological deficits

BACKGROUND The presence of depression in schizophrenia has been well described with regard to stage and symptoms of illness; however, little is known about the possible etiology. METHODS In an effort to advance the understanding of the neurobiology of depression in schizophrenia, we grouped patients with schizophrenia based on their ratings on the 21-item Hamilton Depression Rating Scale. There were 63 patients (35 men, 28 women) in the high (> or = 18) depression group and 81 patients (52 men, 29 women) in the low (< 18) depression group. The groups were compared in demographic, clinical, and eight neuropsychological domains. RESULTS The two groups differed in age at onset of illness, severity of delusions, and performance in a single neuropsychological domain: attention. The specific component of impaired attention was vigilance, with poorest performance seen in women with higher depression scores. CONCLUSION The presence of specific attentional impairment associated with depressive symptoms in schizophrenia is consistent with the hypothesis of frontal lobe dysfunction in depression, because these regions have been implicated in attentional processes.

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.

Effectiveness of an Attention- and Memory-Training Program on Neuropsychological Deficits in Schizophrenia

The effect of two cognitive remediation procedures developed for closed head injury, Attention Process Training (APT) and Prospective Memory Training (PROMT), on neuropsychological deficits in schizophrenia was investigated. Six pa tients with schizophrenia, varying in baseline intellectual function and symptoms, were studied; three in a remediation condition and three in a nonremediated control con dition. Results were evaluated individually for each of the three treated patients. Two of three remediation-treated subjects showed marked improvement on tests of sus tained and divided attention. Untreated patients showed little evidence of change in neuropsychological test performance across a similar time interval, when tested on a subset of the measures administered to remediation-treated patients. The results of this study are discussed with a view toward future studies using larger sample sizes with homogeneous subject populations. Key Words: Schizophrenia—Cognitive—Reha bilitation—Symptoms—Outcome.

164. Neuropsychological functioning in bipolar and schizophrenia groups

Schizophreniaand bipolar disorder are commonpsychiatriciilnesses with similar symptomatology, which emerge in youngadulthoodand tendto run a life-longcourse.In an effort to advancethe understanding of neurobiological differences,we compareda biprh group(n= 11)to a schizophreniagroupmatchedfor certaindemographicvariables(age, sex, race, durationof illness and education).Subjectswere diagnosed according to DSM-fV criteria baaed on the Structured Diagnostic Interview (SCID: First et al.1995) and underwenta comprehensive researchevaluationincludingpsychiatricratingsandneuropsychologicrd evaluationperformedby trainedandexperiencedpsycfriaticandneuropsychologicaltesters.Bipolarand schizophreniagroupswerecompared withrespecttoneuropsychological performancestandardizedtoa healthy controlgroup.Testsof Analysisof Variance(ANOVAs)wereperformed on neuropsychologicalperformanceusing bipolar and schizophrenia ~oups as independentvariablesand the followingdomainscores as dependentvariables:abstraction,attention,verbalmemory,spatialmemOrY,language,spatial abilities,sensoryand motoric.On neuropsychological performsmcebipch and schizophreniagroupsdiffered in the domainof languageonly,wheretheschizophrenia@oupperformedmore poorly than the nonschizophreniagroup. The difference in language functionwillbe furtherexploredby separatingthevariousSubtestswhich comprisethe globalscore.