Monitoring neurocognitive functioning in childhood cancer survivors: evaluation of CogState computerized assessment and the Behavior Rating Inventory of Executive Function (BRIEF)

Abstract Background Many childhood cancer survivors develop neurocognitive impairment, negatively affecting education and psychosocial functioning. Recommended comprehensive neuropsychological testing can be time- and cost- intensive for both institutions and patients and their families. It is important to find quick and easily administered surveillance measures to identify those in need of evaluation. Methods We evaluated, individually and in combination, the sensitivity and specificity of the 1) Behavior Rating Inventory of Executive Functioning-Metacognition Index (BRIEF-MCI), and 2) CogState Composite Index (computerized assessment of cognition) in identifying below grade-level performance on state-administered tests of reading and mathematics among childhood cancer survivors. Results The 45 participants (39% female) were a mean age of 7.1 ± 4.4 years at diagnosis, 14.0 ± 3.0 at evaluation, with a history of leukemia (58%), lymphoma (9%), central nervous system tumors (20%), and other tumors (13%). Impairment on the BRIEF-MCI was associated with low sensitivity (26% reading, 41% mathematics) but stronger specificity (88% reading, 96% mathematics). We found similar associations for the CogState Composite Index with sensitivity of 26% for reading and 29% for mathematics and specificity of 92% for both reading and mathematics. Combining the two measures did not improve sensitivity appreciably (47% reading, 59% mathematics) while reducing specificity (84% reading, 88% mathematics). Conclusions While individuals identified from the BRIEF-MCI or CogState Composite would likely benefit from a full neuropsychological evaluation given the strong specificity, use of these measures as screening tools is limited. With poor sensitivity, they do not identify many patients with academic difficulties and in need of a full neuropsychological evaluation. Continued effort is required to find screening measures that have both strong sensitivity and specificity

A functional magnetic resonance imaging study of left hemisphere language dominance in children.

Functional magnetic resonance imaging is a noninvasive method of assessing language dominance in a pediatric population. To determine the pattern of receptive language lateralization in healthy children. We used functional magnetic resonance imaging to assess an auditory language task in 11 children (7 girls, 4 boys; mean age, 8.5 years). Participants alternately rested and listened to descriptors of nouns presented auditorily, naming the object described silently. Asymmetry indices ([(left - right)/(left + right)]) were calculated for a priori-determined regions of interest. The results showed strong activation bilaterally, with greater activation on the left in the superior and middle temporal gyri. Other areas of activation included the cuneus, the left inferior temporal gyrus, the prefrontal area, and the left fusiform and lingual gyri. Regions of interest analysis of individual scans showed additional activation in the left frontal lobe. Asymmetry indices showed strong left lateralization of the inferior frontal gyrus, middle frontal gyrus, and the Wernicke region. Hemispheric lateralization was clearly demonstrated in 8 children. As in adults, left hemisphere lateralization of receptive language is present at age 8 years

Developmental aspects of language processing: fMRI of verbal fluency in children and adults

We examined developmental differences, in location and extent of fMRI language activation maps, between adults and children while performing a semantic fluency task. We studied 29 adults and 16 children with echo planar imaging BOLD fMRI at 1.5 T using covert semantic verbal fluency (generation of words to categories compared to rest) using a block design. Post task testing was administered to assess performance. Individual data were analyzed with an a priori region of interest approach from t maps (t = 4) and asymmetry indices (AI). Group studies were analyzed using SPM 99 (Wellcome, UK; fixed effect, corrected P < 0.0001). We found no significant differences in location or laterality of activation between adults and children for a semantic verbal fluency task. Adults activated more pixels than children in left inferior frontal gyrus and left middle frontal gyrus, but AIs were the similar across ages (r2 < 0.09). Extent or laterality of activation was not affected by performance (r2 < 0.15). The brain areas that process semantic verbal fluency are similar in children and adults. The laterality of activation does not change appreciably with age and appears to be strongly lateralized by age 7 years. Published 2003 Wiley-Liss, Inc

Observing Behavior and Atypically Restricted Stimulus Control

Restricted stimulus control refers to discrimination learning with atypical limitations in the range of controlling stimuli or stimulus features. In the study reported here, 4 normally capable individuals and 10 individuals with intellectual disabilities (ID) performed two-sample delayed matching to sample. Sample-stimulus observing was recorded with an eye-tracking apparatus. High accuracy scores indicated stimulus control by both sample stimuli for the 4 nondisabled participants and 4 participants with ID, and eye tracking data showed reliable observing of all stimuli. Intermediate accuracy scores indicated restricted stimulus control for the remaining 6 participants. Their eye-tracking data showed that errors were related to failures to observe sample stimuli and relatively brief observing durations. Five of these participants were then given interventions designed to improve observing behavior. For 4 participants, the interventions resulted initially in elimination of observing failures, increased observing durations, and increased accuracy. For 2 of these participants, contingencies sufficient to maintain adequate observing were not always sufficient to maintain high accuracy; subsequent procedure modifications restored it, however. For the 5th participant, initial improvements in observing were not accompanied by improved accuracy, an apparent instance of observing without attending; accuracy improved only after an additional intervention that imposed contingencies on observing behavior. Thus, interventions that control observing behavior seem necessary but may not always be sufficient for the remediation of restricted stimulus control