Lesion location and repeatable battery for the assessment of neuropsychological status performance in acute ischemic stroke.

The validity of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was evaluated in a sample of acute ischemic stroke patients. A total of 164 ischemic stroke patients with anterior fossa lesions were divided into groups according to lesion laterality (left, right, or bilateral) and location (cortical versus subcortical) as determined by CT and/or MRI findings. The hypotheses for this study were: (1) that left hemispheric stroke patients would perform better than their counterparts on the Visuospatial/Constructional and Attention Indexes; (2) that right hemisphere stroke patients would outperform their counterparts on the Immediate Memory, Delayed Memory, and Language Indexes; (3) that patients with subcortical lesions would outperform those with cortical lesions on the Language, Immediate Memory, and Delayed Memory indexes; and (4) that patients with cortical lesions would outperform those with subcortical lesions on the Attention and Visuospatial/Constructional Indexes. A multivariate analysis of variance (MANOVA) disclosed significant main effects for both lesion side and location, with no location by side interaction. Group comparisons of the five RBANS index scores disclosed modest effects for side of lesion, with right hemisphere patients outperforming those with left sided and bilateral lesions on the Immediate and Delayed Memory, and Language Index Scores. Right hemisphere stroke patients also outperformed left and bilateral lesion patients on the Attention Index. The left hemisphere patients outperformed the right hemisphere and bilateral patients on the Visuospatial/Constructional Index. The effect for location was significant only for the Visuospatial/Constructional Index where the subcortical patients outperformed the cortical patients.

Differential effects of stress on adult hippocampal cell proliferation in low and high aggressive mice.

Male wild house mice selected for a long (LAL) or a short (SAL) latency to attack a male intruder generally show opposing behavioural coping responses to environmental challenges. LAL mice, unlike SAL mice, adapt to novel challenges with a highly reactive hypothalamic-pituitary-adrenal axis and show an enhanced expression of markers for hippocampal plasticity. The present study aimed to test the hypothesis that these features of the more reactive LAL mice are reflected in parameters of hippocampal cell proliferation. The data show that basal cell proliferation in the subgranular zone (SGZ) of the dentate gyrus, assessed by the endogenous proliferation marker Ki-67, is lower in LAL than in SAL mice. Furthermore, application of bromodeoxyuridine (BrdU) over 3 days showed an almost two-fold lower cell proliferation rate in the SGZ in LAL versus SAL mice. Exposure to forced swimming resulted, 24 h later, in a significant reduction in BrdU + cell numbers in LAL mice, whereas cell proliferation was unaffected by this stressor in SAL mice. Plasma corticosterone and dentate gyrus glucocorticoid receptor levels were higher in LAL than in SAL mice. However, no differences between the SAL and LAL lines were found for hippocampal NMDA receptor binding. In conclusion, the data suggest a relationship between coping responses and hippocampal cell proliferation, in which corticosterone may be one of the determinants of line differences in cell proliferation responses to environmental challenges.

The validity of the repeatable battery of neuropsychological status in acute stroke.

The construct validity of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was investigated in a sample of 210 acute ischemic stroke patients seen on an inpatient rehabilitation unit. Intercorrelations between the six index scores were found to be relatively consistent with previously published work. A principal components analysis yielded a two-factor (Language/Verbal Memory and Visuospatial/Visual Memory) solution that accounted for 61% of the variance. Correlations generated between the resulting factor scores, the Controlled Oral Word Association Test (COWA), the Visual Form Discrimination Test (VFD), Boston Diagnostic Aphasia Examination (BDAE) Complex Ideational Material Test (CIM), the presence of neglect as determined by Line Bisection Test performance, and the Mini Mental Status Examination (MMSE) supported the validity of these factors. A comparison of the obtained factor scores in a subgroup of 111 left and right hemispheric stroke patients showed that the left hemispheric stroke patients performed more poorly on the Language/Verbal Memory factor score than did right hemispheric stroke patients while the converse was true for the Visuospatial/Visual Memory factor score. Implications for the construct validity of the RBANS and its use and interpretation in clinical assessment are discussed.

Combined uridine and choline administration improves cognitive deficits in spontaneously hypertensive rats.

Rationale. Hypertension is considered a risk factor for the development of cognitive disorders, because of its negative effects on cerebral vasculature and blood flow. Genetically induced hypertension in rats has been associated with a range of cognitive impairments. Therefore, spontaneously hypertensive rats (SHR) can potentially be used as a model for cognitive deficits in human subjects. Consecutively, it can be determined whether certain food components can improve cognition in these rats. Objective. The present study aimed to determine whether SHR display specific deficits in attention, learning, and memory function. Additionally, effects of chronic uridine and choline administration were studied. Methods. 5-7 months old SHR were compared with normotensive Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats. (a) The operant delayed non-matching-to-position (DNMTP) test was used to study short-term memory function. (b) The five-choice serial reaction time (5-CSRT) task was used to assess selective visual attention processes. (c) Finally, the Morris water maze (MWM) acquisition was used as a measure for spatial learning and mnemonic capabilities. Results. (1) SHR exhibited significantly impaired performance in the 5-CSRT test in comparison with the two other rat strains. Both the SHR and WKY showed deficits in spatial learning when compared with the SD rats. (2) Uridine and choline supplementation normalized performance of SHR in the 5-CSRT test. (3) In addition, uridine and choline treatment improved MWM acquisition in both WKY and SHR rats. Conclusion. The present results show that the SHR have a deficiency in visual selective attention and spatial learning. Therefore, the SHR may provide an interesting model in the screening of substances with therapeutic potential for treatment of cognitive disorders. A combination of uridine and choline administration improved selective attention and spatial learning in SHR.

Pallidotomy: a comparison of responders and nonresponders.

OBJECTIVE: We reviewed a prospective series of 32 unilateral, large-volume, microelectrode-guided posteroventral pallidotomies to determine the differences between responsive and nonresponsive patients. METHODS: Our patients underwent extensive pre- and postoperative evaluations. One year postoperatively, we correlated the outcomes of 25 patients with their histories, physical findings, neuropsychological assessments, and lesion characteristics to further understand the indications, limitations, and pitfalls of unilateral pallidotomy. Our group judged responsiveness by comparing the preoperative total Unified Parkinson's Disease Rating Scale off-state scores with those obtained 1 year postoperatively. A score indicating greater than 20% improvement at 1-year follow-up was rated a good outcome; improvement of greater than 40% was rated an excellent outcome. RESULTS: Although most patients sustained long-term benefits, some demonstrated little or no improvement. Patient and lesion factors influenced outcome. Younger age (<60 yr), tremor, unilateral predominance, L-dopa responsiveness, motor fluctuations with dyskinesia, and good lesion placement predicted a good response to unilateral pallidotomy. Advanced age (>70 yr), absence of tremor, increased duration of disease, reduced responsiveness to L-dopa, frontal behavioral changes, prominent apraxic phenomena, and improper lesion placement predicted a poor response. CONCLUSION: Unilateral, large-volume pallidotomy with precise lesion control provides long-lasting benefits for carefully selected patients.

Wechsler Adult Intelligence Scale-Revised Block Design broken configuration errors in nonpenetrating traumatic brain injury.

Final broken configuration errors on the Wechsler Adult Intelligence Scale-Revised (WAIS-R; Wechsler, 1981) Block Design subtest were examined in 50 moderate and severe nonpenetrating traumatically brain injured adults. Patients were divided into left (n = 15) and right hemisphere (n = 19) groups based on a history of unilateral craniotomy for treatment of an intracranial lesion and were compared to a group with diffuse or negative brain CT scan findings and no history of neurosurgery (n = 16). The percentage of final broken configuration errors was related to injury severity, Benton Visual Form Discrimination Test (VFD; Benton, Hamsher, Varney, & Spreen, 1983) total score and the number of VFD rotation and peripheral errors. The percentage of final broken configuration errors was higher in the patients with right craniotomies than in the left or no craniotomy groups, which did not differ. Broken configuration errors did not occur more frequently on designs without an embedded grid pattern. Right craniotomy patients did not show a greater percentage of broken configuration errors on nongrid designs as compared to grid designs.

Do recognition-free recall discrepancies detect retrieval deficits in closed-head injury? An exploratory analysis with the California verbal learning test.

The present study examined the validity of the Recognition Discriminability-Long Delay Free Recall discrepancy from the California Verbal Learning Test (CVLT) as a sign of retrieval deficits in closed-head injury (CHI). Discrepancy and nondiscrepancy groups who differed in their Recognition Discriminability performance but were equated on Long-Delay Free Recall were compared on indices hypothesized to reveal performance patterns consistent with retrieval deficits. Results showed that the discrepancy group produced fewer intrusions. The two groups did not differ in their consistency of recall or relative degree of benefit from semantic cuing. Additional analysis using a discrepancy group with normal Recognition Discriminability scores but abnormal Long-Delay Free Recall performance did not alter these results. The hypotheses were not supported when patients with language deficits were excluded. The findings did not support the use of this discrepancy from the CVLT as a marker for retrieval deficits in CHI.