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Purpose: Memory impairment is an early-delayed effect of radiotherapy (RT). The prospective longitudinal measurement of the cognitive phase effects from RT was conducted on treated and untreated brain tumor patients. The study design investigated semantic vs. perceptual and visual vs. verbal memory to determine the most disease-specific measure of RT-related changes and understanding of the neurotoxicity from RT to the brain., Methods and Materials: Tests of memory that had previously shown RT-related phasic changes were compared with experimental tests of memory to test hypotheses about cognition targeted to the neural toxicity of RT. The results from 41 irradiated and 29 nonirradiated patients with low-grade, supratentorial tumors were analyzed. The methods controlled for comorbid white matter risk, recurrence, interval after treatment, and age (18-69 years). The effects were examined before RT and at three points after RT to 1 year using a mixed effects model that included interval, group, surgical status, medication use, practice, and individual random effects. Four new tests of memory and other candidate cognitive tests were investigated, and a post hoc analysis of a comprehensive battery of tests was performed to identify the cognitive processes most specific to RT., Results: The RT effects on memory were identified in the treated group only; among the new tests of memory and the complete neurocognitive battery, the RT effects were significant only for delayed recall (p < 0.009) and interval to recognize (p < 0.002). Tumor location was not related to the treatment effect. Memory decline was specific to retrieval of semantic memories; a double dissociation of semantic from perceptual visual memory was demonstrated in the RT group., Conclusions: These results implicate memory dependent on the semantic cortex and the hippocampal memory system. A cognitive measurement that is brief but specific to neural mechanisms is effective and feasible for studies of RT damage., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: This study prospectively examines the correlation between neurocognitive (NC) functioning and problem behavior in early adolescence., Methods: As part of a longitudinal study, African American urban youths of lower socioeconomic status, mean age 12.1 years (SD=1.2, n=111), were administered a battery of 16 NC tasks assessing eight NC systems (two tasks per system) including four systems primarily associated with frontal cortex and four primarily associated with nonfrontal cortex. The former systems included (1) executive cognitive functioning (ECF), (2) cognitive control, (3) working memory, and (4) reward processing. The latter systems included (5) receptive language, (6) spatial cognition, (7) visual cognition, and (8) memory. The Teacher's Report Form of the Achenbach System of Empirically Based Assessment was performed approximately at the same age that the NC assessments were performed. Bivariate correlations were calculated between the eight NC system composite scores and the externalizing scores., Results: Significant negative relationships were found between ECF and receptive language ability and externalizing behavior. Further analyses, using linear regression, showed that receptive language was more predictive of externalizing behavior than ECF., Conclusion: Based on these results we conclude that (1) NC functioning, specifically in ECF and in receptive language systems, was associated with adolescent problem behavior and (2) receptive language was more strongly associated with problem behavior than ECF.