Memory and attention after childhood brain tumors

Potential Anomalous Findings on the Cerberus Subtest of the TEACh 2 in a Pediatric Neuro-Oncology Cohort

INTRODUCTION

The Test of Everyday Attention for Children 2 (TEA-Ch 2) is a rigorously tested measure of attention, often used in pediatric neuro-oncology settings. Data from one Primary Treatment Centre found a high proportion of children scored in the highest range on the Cerberus subtest. This brief report attempts to answer the question: Does the Cerberus subtest of the TEA-Ch 2 provide outlying scores in the pediatric neuro-oncology population?

METHODS

Data representing 62 Cerberus assessments from four primary treatment centers were analyzed.

RESULTS

Data showed a substantially higher level of performance on the Cerberus subtest compared to other TEA-Ch2 subtests. Scores were not only higher than expected relative to children's performance on other subtests but also higher than would be expected in the general population.

DISCUSSION

Within our data, performance on the Cerberus subset of the TEA-Ch 2 yields somewhat questionable data from which to draw conclusions regarding sustained attentional ability in a pediatric neuro-oncology cohort.

Neurocognitive development after pediatric brain tumor - a longitudinal, retrospective cohort study

Survivors of Pediatric Brain Tumors (PBTs) treated with cranial radiation therapy (CRT) often experience a decline in neurocognitive test scores. Less is known about the neurocognitive development of non-irradiated survivors of PBTs. The aim of this study was to statistically model neurocognitive development after PBT in both irradiated and non-irradiated survivors and to find clinical variables associated with the rate of decline in neurocognitive scores. A total of 151 survivors were included in the study. Inclusion criteria: Diagnosis of PBT between 2001 and 2013 or earlier diagnosis of PBT and turning 18 years of age between 2006 and 2013. Exclusion criteria: Death within a year from diagnosis, neurocutaneous syndromes, severe intellectual disability. Clinical neurocognitive data were collected retrospectively from medical records. Multilevel linear modeling was used to evaluate the rate of decline in neurocognitive measures and factors associated with the same. A decline was found in most measures for both irradiated and non-irradiated survivors. Ventriculo-peritoneal (VP) shunting and treatment with whole-brain radiation therapy (WBRT) were associated with a faster decline in neurocognitive scores. Male sex and supratentorial lateral tumor were associated with lower scores. Verbal learning measures were either stable or improving. Survivors of PBTs show a pattern of decline in neurocognitive scores irrespective of treatment received, which suggests the need for routine screening for neurocognitive rehabilitation. However, survivors treated with WBRT and/or a VP shunt declined at a faster rate and appear to be at the highest risk of negative neurocognitive outcomes and to have the greatest need for neurocognitive rehabilitation.

Translating methylphenidate's efficacy on selective and sustained attentional deficits to those reported in childhood cancer survivors: A qualitative review

Whilst an increasing number of children survive previously incurable cancers of the central nervous system (CNS), associated treatments often result in significant neurocognitive late effects. Methylphenidate provides some signs of alleviating cognitive difficulties in different pediatric groups; however, a minimal amount of systematic work has explored its effectiveness isolated to vulnerable attentional domains. The current review aimed to explore the effectiveness of methylphenidate isolated to two attentional domains (sustained and selective attention)-with an aim to substantiate its utility in childhood cancer survivors. Five databases were comprehensively searched for relevant articles. A purpose-developed tool was used to assess each study's robustness and research quality. Eleven out of 1,865 identified articles were included within the review. Studies drew upon five clinical populations. Individual attentional domains demonstrate variation in their response to methylphenidate. Sustained attention demonstrated the most consistent benefit of methylphenidate, reported largely in attention-deficit/hyperactivity disorder (ADHD) groups. Gains in selective attention and higher-order cognitive functions appeared to follow initial gains in sustained attention. Childhood cancer survivors report greater gains in selective attention compared to sustained attention. Higher doses may yield greater benefit for children with more diffuse attentional deficits. There is a need to improve the validity of current attentional measures before further methylphenidate trials are conducted.

Considerations for Reliable Digit Span as a performance validity test for long-term survivors of childhood brain tumors

The Reliable Digit Span (RDS) is a performance validity test (PVT) used widely within non-clinical samples, but its utility is in question in clinical groups with cognitive impairment. To investigate, RDS scores were calculated and correlated with the Neurological Predictor Scale, an informant-reported Activities of Daily Living score, and a proxy measure of intelligence (Vocabulary) for 83 adult survivors of childhood brain tumors and 105 healthy controls. Analyses were covaried for age at examination. Participants were divided into passing and failing groups at each RDS cutoff, and ANCOVAs for each of the three variables of interest covaried for age at the examination were run. RDS was correlated with all three variables of interest in survivors but only Vocabulary in controls. At the ≤7 cutoff, passing and failing survivors demonstrated significant differences across all variables of interest, while passing and failing controls differed only on Vocabulary. Differences were also found between passing and failing survivors at lower cutoffs. RDS is related to and likely impacted by various neurological and cognitive challenges faced by brain tumor survivors. Using the standard RDS cutoff of ≤7 may result in inaccurate interpretation of valid performance in this population; therefore, the use of other PVTs is recommended.

Functional Connectivity Networks and Their Recruitment During Working Memory Tasks in Adult Survivors of Childhood Brain Tumors

Background: Assessments of functional connectivity of default mode network (DMN) and positive task-related networks (TRNs) using independent component analysis (ICA) may help describe long-term effects of childhood brain tumors and adjuvant treatments. Methods: Aiming to identify potential neuronal markers that may aid in prognosis and inform interventions to optimize outcomes, this study used ICA to evaluate the presence of functional connectivity networks and their recruitment during a letter n-back task in 23 adult survivors of childhood posterior fossa tumors (9 low grade, 14 high grade) at least 5 years past diagnosis compared with 40 age- and sex-matched healthy peers. Results: DMN components generally demonstrated increasing disengagement as task difficulty increased, and relationships between effective DMN disengagement and improved performance were observed in healthy controls (HCs). Low-grade brain tumor survivors (LGS) demonstrated unique patterns in DMN recruitment that suggested increased involvement of the medial prefrontal cortex in LGS during tasks. TRN components generally demonstrated increasing engagement, which was related to improved task performance in HCs for one executive control network (ECN) component. High-grade brain tumor survivors (HGS) demonstrated distinct challenges recruiting an ECN component at more difficult task levels and showed a relationship between recruitment of another ECN component and task performance, indicating a potential compensatory mechanism for some HGS. Conclusions: Findings suggest the importance of cognitive intervention in both survivor groups and the necessity to track LGS despite their cognitive abilities often resembling those of their healthy peers. Impact statement Distinct functional connectivity patterns were identified between both adult survivor of childhood brain tumor groups and peers during attention and working memory tasks, reflecting different damage and recovery from treatment. Survivors of low-grade tumors demonstrated unique patterns of recruitment of default mode network components in the context of similar cognitive abilities, whereas survivors of high-grade tumors demonstrated poorer cognitive abilities and may be utilizing compensatory executive control network components in the face of challenging tasks. Long-term clinical follow-up and cognitive remediation is warranted for both groups, including low grade cerebellar tumor patients who have traditionally not been monitored as closely.

Neuropsychological Consequences for Survivors of Childhood Brain Tumor in Malaysia

Objective: This study aimed to evaluate neuropsychological consequences in survivors of childhood brain tumor.

Method: A case-control study was conducted over a period of 4 months in a tertiary referral center in Kuala Lumpur, Malaysia. Fourteen survivors of childhood brain tumor aged 7–18 years, who were off-treatment for at least 1 year and were in remission, and 31 unrelated healthy controls were recruited. The median age at diagnosis was 8.20 years (range: 0.92–12.96 years). The diagnoses of brain tumors were medulloblastoma, germ cell tumor, pineocytoma, pilocystic astrocytoma, suprasellar germinoma, and ependymoma. Eleven survivors received central nervous system irradiation. Seven tasks were selected from the Amsterdam Neuropsychological Tasks program to evaluate alertness (processing speed), and major aspects of executive functioning, such as working memory capacity, inhibition, cognitive flexibility, and sustained attention. Speed, stability and accuracy of responses were the main outcome measures.

Results: Survivors of childhood brain tumor showed statistically significant poorer performance on all tasks compared to healthy controls. Both processing speed and accuracy were impaired in the survivors, in particular under more complex task conditions. The survivors demonstrated deficits in alertness, sustained attention, working memory capacity, executive visuomotor control, and cognitive flexibility. Longer duration off treatment appeared to be correlated with poorer alertness, memory capacity, and inhibition.

Conclusion: Survivors of childhood brain tumor in our center showed impaired neuropsychological functioning. Development of less toxic treatment protocols is important to prevent late effects of cognitive deficits in survivors of childhood brain tumor.

Neuropsychological consequences of childhood medulloblastoma and possible interventions: A review

BACKGROUND

Children who have been treated for a medulloblastoma often suffer long-term cognitive impairments that often negatively affect their academic performance and quality of life. In this article, we will review the neuropsychological consequences of childhood medulloblastoma and discuss the risk factors known to influence the presence and severity of these cognitive impairments and possible interventions to improve their quality of life.

METHODS

This narrative review was based on electronic searches of PubMed to identify all relevant studies.

RESULTS

Although many types of cognitive impairments often emerge during a child's subsequent development, the core cognitive domains that are most often affected in children treated for a medulloblastoma are processing speed, attention and working memory. The emergence and magnitude of these deficits varies greatly among patients. They are influenced by demographic (age at diagnosis, parental education), medical and treatment-related factors (perioperative complications, including posterior fossa syndrome, radiation therapy dose, etc.), and the quality of interventions such as school adaptations provided to the child or rehabilitation programs that focus on cognitive skills, behavior and psychosocial functioning.

CONCLUSION

These patients require specialized and coordinated multidisciplinary rehabilitation follow-up that provides timely and adapted assessments and culminates in personalized intervention goals being set with the patient and the family. Follow-up should be continued until referral to adult services.

The Neurological Predictor Scale: A predictive tool for long-term core cognitive outcomes in survivors of childhood brain tumors

OBJECTIVE

Prior research has demonstrated the reliability and validity of the Neurological Predictor Scale (NPS) in relation to intelligence and adaptive functioning in survivors of pediatric brain tumors. To extend these findings, this study examined the relationship between the NPS and core neurocognitive skills hypothesized to underlie broad outcome measures of IQ and adaptive functioning.

METHOD

Sixty-one adulthood survivors of childhood brain cancers (M_age = 24 years, SD = 6) on average 16 years after diagnosis completed neuropsychological assessments examining attention (Wechsler Memory Scale Digit Span Forward), processing speed (Symbol Digit Modalities Test), and working memory (Auditory Consonant Trigrams). The medical information necessary to compute the NPS was extracted from a thorough medical record review.

RESULTS

The NPS score significantly predicted processing speed (R² = 0.28, P < 0.05) and working memory (R² = 0.15, P < .05) outcomes over and above each individual risk factor. NPS was significantly associated with attention outcomes after covarying for age (R² = 0.13, P < 0.05) over and above each risk factor except presence of hormone deficiency, hydrocephalus, and chemotherapy. These three variables were not significantly associated with attention outcomes in this sample.

CONCLUSIONS

Our findings suggest that survivors with more treatments and neurological sequelae experience greater deficits in working memory, processing speed, and attention. Further, the NPS affords the ability to predict how cumulative neurological factors impact core cognitive outcomes many years after initial diagnosis.

Cognitive dysfunction in children with brain tumors at diagnosis

BACKGROUND

Survivors of brain tumors have a high risk for a wide range of cognitive problems. These dysfunctions are caused by the lesion itself and its surgical removal, as well as subsequent treatments (chemo- and/or radiation therapy). Multiple recent studies have indicated that children with brain tumors (BT) might already exhibit cognitive problems at diagnosis, i.e., before the start of any medical treatment. The aim of the present study was to investigate the baseline neuropsychological profile in children with BT compared to children with an oncological diagnosis not involving the central nervous system (CNS).

METHODS

Twenty children with BT and 27 children with an oncological disease without involvement of the CNS (age range: 6.1-16.9 years) were evaluated with an extensive battery of neuropsychological tests tailored to the patient's age. Furthermore, the child and his/her parent(s) completed self-report questionnaires about emotional functioning and quality of life. In both groups, tests were administered before any therapeutic intervention such as surgery, chemotherapy, or irradiation. Groups were comparable with regard to age, gender, and socioeconomic status.

RESULTS

Compared to the control group, patients with BTs performed significantly worse in tests of working memory, verbal memory, and attention (effect sizes between 0.28 and 0.47). In contrast, the areas of perceptual reasoning, processing speed, and verbal comprehension were preserved at the time of measurement.

CONCLUSION

Our results highlight the need for cognitive interventions early in the treatment process in order to minimize or prevent academic difficulties as patients return to school.

Effect of motivation on academic fluency performance in survivors of pediatric medulloblastoma

It has been proposed previously that extrinsic motivation may enable survivors of childhood medulloblastoma to significantly improve aspects of neurocognitive performance. In healthy populations, enhanced motivation has been shown to promote academic fluency, a domain likely more relevant to the educational outcomes of pediatric medulloblastoma survivors than academic skill development. The present study investigates the effect of enhanced extrinsic motivation on fluent (i.e., accurate and efficient) academic performance in pediatric medulloblastoma survivors. Participants were 36 children, ages 7-18, who had completed treatment for medulloblastoma. Participants completed a neuropsychological battery that included administration of equivalent tasks on Forms A and B of the Woodcock-Johnson III Tests of Achievement. Half were randomly assigned to an incentive condition prior to the administration of Form B. Provision of a performance-based incentive resulted in statistically significant improvement, but not normalization of function, in performance on measures of academic fluency. No demographic, treatment-related, academic, neuropsychological, or self-perception variables predicted response to incentive. Findings suggest that academic performance of survivors may significantly improve under highly motivating conditions. In addition to implications for educational services, this finding raises the novel possibility that decreased motivation represents an inherent neuropsychological deficit in this population and provides a rationale for further investigation of factors affecting individual differences in motivational processes. Further, by examining effort in a context where effort is not inherently suspect, present findings also significantly contribute to the debate regarding the effects of effort and motivation on neuropsychological performance.

School Competence and Fluent Academic Performance: Informing Assessment of Educational Outcomes in Survivors of Pediatric Medulloblastoma

Academic difficulties are widely acknowledged but not adequately studied in survivors of pediatric medulloblastoma. Although most survivors require special education services and are significantly less likely than healthy peers to finish high school, measured academic skills are typically average. This study sought to identify potential factors associated with academic difficulties in this population and focused on school competence and fluent academic performance. Thirty-six patients (ages 7-18 years old) were recruited through the Departments of Neurosurgery and Neuro-Oncology at Children's Medical Center Dallas and Cook Children's Medical Center in Fort Worth, TX. Participants completed a neuropsychological screening battery including selected Woodcock-Johnson III Tests of Achievement subtests. Parents completed the Child Behavior Checklist. School competence was significantly correlated with measured academic skills and fluency. Basic academic skill development was broadly average, in contrast to significantly worse fluent academic performance. School competence may have utility as a measure estimating levels of educational success in this population. Additionally, academic difficulties experienced by childhood medulloblastoma survivors may be better captured by measuring deficits in fluent academic performance rather than skills. Identification of these potential factors associated with educational outcomes of pediatric medulloblastoma survivors has significant implications for research, clinical assessment, and academic services/interventions.

Cognitive disorders in pediatric medulloblastoma: what neuroimaging has to offer

Medulloblastomas are the most common malignant childhood brain tumors arising in the posterior fossa. Treatment improvements for these tumors have meant that there are a greater number of survivors, but this long-term patient survival has increased the awareness of resulting neurocognitive deficits. Impairments in attention, memory, executive functions, and intelligence quotient demonstrate that the cerebellum likely plays a significant role in numerous higher cognitive functions such as language, cognitive, and emotional functions. In addition, children with medulloblastoma not only have cerebellar lesions but also brain white matter damages due to radiation and chemotherapy. Functional neuroimaging, a noninvasive method with many advantages, has become the standard tool in clinical and cognitive neuroscience research. By reviewing functional neuroimaging studies, this review aims to clarify the role of the cerebellum in cognitive function and explain more clearly cognitive sequelae due to polytherapy in children with medulloblastoma. This review suggests that the posterior cerebellar lobes are crucial to maintaining cognitive performance. Clinical investigations could help to better assess the involvement of these lobes in cognitive functions.

Working memory abilities among children treated for medulloblastoma: parent report and child performance

OBJECTIVE

We investigated the 5-year postsurgical developmental trajectory of working memory (WM) in children with medulloblastoma using parent and performance-based measures.

METHOD

This study included 167 patients treated for medulloblastoma. Serial assessments of WM occurred at predetermined time points for 5 years.

RESULTS

There was a subtle, statistically significant increase in parental concern about WM, coupled with a statistically significant decrease in age-standardized scores on performance-based measures. However, whole-group mean scores on both parent and performance-based measures remained in the age-expected range. Posterior fossa syndrome was consistently associated with poorer WM. Younger age at treatment and higher treatment intensity were associated with greater negative change in WM performance only.

CONCLUSIONS

Most children treated for medulloblastoma display WM within the age-appropriate range according to parent report and performance. However, the subtle negative changes over time and identified subgroups at increased risk highlight the need for ongoing monitoring of this population.

Cognitive function in children with brain tumors in the first year after diagnosis compared to healthy matched controls

BACKGROUND

Improved survival of children with brain tumors (BTs) has increased focus on ameliorating morbidity. To reduce the risk of progressive cognitive decline, remedial strategies need to be instituted early, based upon accurate appraisal of need, yet few studies have investigated cognition in BT children early post-diagnosis. The study aims were to investigate cognition in children with primary BTs 1, 6, and 12 months post-diagnosis compared with healthy children, exploring the impact of disease and treatment variables.

METHODS

Forty-eight children aged 2-16 years with primary BTs, referred to a Regional Neurosurgical Unit over the 2-year study period were eligible for enrollment. The "best friends" model was used to recruit matched controls. Cognition was assessed using age-appropriate Wechsler Intelligence scales; Children's Memory Scale; Test of Everyday Attention for Children, and Wechsler Quicktest.

RESULTS

Patients with BTs had significantly reduced performance compared to controls early post-diagnosis in tests of Performance IQ, processing speed, verbal and visual memory, and selective attention. Improved performance over 12 months was seen in patients with BTs although also, for some measures, in controls. Significant deficits in cognitive performance were seen one year post-diagnosis for Verbal IQ; processing speed, visual and verbal immediate memory, and selective attention. Infratentorial site, high tumor grade, hydrocephalus, radiotherapy, and chemotherapy were associated with poorer functioning.

CONCLUSION

Early cognitive impairment is present in BT children, sometimes prior to radiotherapy/chemotherapy treatment, and is associated with hydrocephalus, high tumor grade and infratentorial site. Future studies should investigate the role of early rehabilitation in improving cognition.

Feasibility and efficacy of a computer-based intervention aimed at preventing reading decoding deficits among children undergoing active treatment for medulloblastoma: results of a randomized trial

OBJECTIVE

To investigate the feasibility of a computer-based reading intervention completed by patients diagnosed with a brain tumor.

METHODS

Patients were randomized to the intervention (n = 43) or standard of care group (n = 38). The intervention consisted of 30 sessions using Fast ForWord® exercises in a game-like format. Change in reading decoding scores over time since diagnosis was examined. Gender, race, parent education, parent marital status, and age at diagnosis were examined as covariates.

RESULTS

17 patients (39.5%) were able to complete the target goal of 30 intervention sessions. Females had significantly greater training time than males (p = .022). Age at diagnosis was associated with average training time/session for females (r = .485, p = .041). No significant differences were found in reading scores between the randomized groups.

CONCLUSIONS

The study was well accepted by families and adherence by patients undergoing radiation therapy for medulloblastoma was moderate. Suggestions for improved methodology are discussed.

Neurocognitive consequences of a paediatric brain tumour and its treatment: a meta-analysis

AIM

This meta-analysis provides a systematic review of studies into intellectual and attentional functioning of paediatric brain tumour survivors (PBTS) as assessed by two widely used measures: the Wechsler Intelligence Scale for Children (3rd edition; WISC-III) and the Conners' Continuous Performance Test (CPT).

METHOD

Studies were located that reported on performance of PBTS (age range 6-16y). Meta-analytic effect sizes were calculated for Full-scale IQ, Performance IQ, and Verbal IQ as measured by the WISC-III, and mean hit reaction time, errors of omission, and errors of commission as measured by the CPT. Exploratory analyses investigated the possible impacts of treatment mode, tumour location, age at diagnosis, and time since diagnosis on intelligence.

RESULTS

Twenty-nine studies were included: 22 reported on the WISC-III in 710 PBTS and seven on CPT results in 372 PBTS. PBTS performed below average (p(s) <0.001) on Full-scale IQ (Cohen's d=-0.79), Performance IQ (d=-0.90), and Verbal IQ (d=-0.54). PBTS committed more errors of omission than the norm (d=0.82, p<0.001); no differences were found for mean hit reaction time and errors of commission. Cranial radiotherapy, chemotherapy, and longer time since diagnosis were associated with lower WISC-III scores (p(s) <0.05).

INTERPRETATION

PBTS have seriously impaired intellectual functioning and attentiveness. Being treated with cranial radiotherapy and/or chemotherapy as well as longer time since diagnosis leads to worse intellectual functioning.

Computerized assessment of cognitive late effects among adolescent brain tumor survivors

Advantages of computerized assessment of neuropsychological functions include improved standardization and increased reliability of response time variables. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is a computerized battery developed for monitoring recovery following mild brain injuries that assesses attention, memory and processing speed. Despite evidence that core areas of deficit among cancer survivors are those assessed by ImPACT, it has not previously been used with this population. Twenty four childhood brain tumor (BT) survivors treated with conformal radiation therapy (mean age = 15.7 ± 1.6; mean age at irradiation = 9.8 ± 2.5), twenty solid tumor (ST) survivors treated without CNS-directed therapy (mean age = 16.2 ± 1.8) and twenty healthy siblings (mean age = 15.1 ± 1.6 years) were administered an age modified version of ImPACT. Additional computerized measures of working memory and recognition memory were administered. Univariate ANOVAs revealed group differences (p < 0.05) on measures of recognition memory, spatial working memory, processing speed and reaction time, with BT survivors performing significantly worse than ST survivors and siblings. Pearson correlation coefficients revealed significant associations between ImPACT memory tasks and computerized forced choice recognition tasks (rs = 0.30-0.33, p < 0.05). Multiple surgical resections, hydrocephalus and CSF shunt placement most consistently predicted worse ImPACT performance using linear mixed models (p < 0.05). The ImPACT test battery demonstrated sensitivity to cognitive late effects experienced by some BT survivors with clinical predictors of performance consistent with the pediatric oncology literature. Correlations with measures of similar constructs provide evidence for convergent validity. Findings offer initial support for the utility of ImPACT for monitoring of cognitive late effects.

Working memory performance among childhood brain tumor survivors

While longitudinal studies of children treated for brain tumors have consistently revealed declines on measures of intellectual functioning, greater specification of cognitive changes following treatment is imperative for isolating vulnerable neural systems and developing targeted interventions. Accordingly, this cross-sectional study evaluated the performance of childhood brain tumor survivors (n = 50) treated with conformal radiation therapy, solid tumor survivors (n = 40) who had not received central nervous system (CNS) -directed therapy, and healthy sibling controls (n = 40) on measures of working memory [Digit Span and computerized self-ordered search (SOS) tasks]. Findings revealed childhood brain tumor survivors were impaired on both traditional [Digit Span Backward- F(2,127) = 5.98; p < .01] and experimental [SOS-Verbal- F(2,124) = 4.18; p < .05; SOS-Object- F(2,126) = 5.29; p < .01] measures of working memory, and performance on working memory measures correlated with intellectual functioning (Digit Span Backward- r = .45; p < .0001; SOS- r = -.32 to -.26; p < .01). Comparison of performance on working memory tasks to recognition memory tasks (computerized delayed match-to-sample) offered some support for greater working memory impairment. This pattern of findings is consistent with vulnerability in functional networks that include prefrontal brain regions and has implications for the clinical management of children with brain tumors.

Cardiorespiratory fitness in survivors of pediatric posterior fossa tumor

Advances in medical therapies have greatly improved survivorship rates in children diagnosed with brain tumor; as a result, morbidities associated with survivorship have become increasingly important to identify and address. In general, pediatric posterior fossa tumor survivors tend to be less physically active than peers. This may be related to late effects of diagnosis and treatment, including cardiovascular, endocrine, psychological, and neurocognitive difficulties. Exercise has been shown to be effective in improving physical functioning, mood, and even cognitive functioning. Consequently, the benefits of physical exercise need to be explored and incorporated into the daily lives of pediatric posterior fossa tumor survivors. The primary aim of the present study was to establish the feasibility and safety of cardiorespiratory fitness testing in pediatric posterior fossa tumor survivors who had received cranial radiation therapy. In addition, comparing our cohort with previously published data, we found that pediatric posterior fossa tumor survivors tended to be less fit than children with pulmonary disease and healthy controls and approximately as fit as children with chronic heart disease and survivors of other types of childhood cancer. The importance of cardiorespiratory fitness in pediatric posterior fossa tumor survivors is discussed along with implications for future directions.

Long-term follow-up of children treated for high-grade gliomas: children's oncology group L991 final study report

PURPOSE

High-grade gliomas of the CNS are characterized by poor treatment response and prognosis for long-term survival. The Children's Oncology Group (COG) L991 study investigated the neuropsychological, behavioral, and quality of life (QoL) outcomes after treatment on the Children's Cancer Group (CCG) trial for high-grade gliomas (CCG-945).

PATIENTS AND METHODS

Fifty-four patients (29 males, 25 females) with a median age of 8.8 years at diagnosis (range, 0.2 to 19.5 years) were enrolled at 25 institutions in North America, representing 81% of available survivors; median length of follow-up was 15.1 years (range, 9.5 to 19.2 years), and median age at study evaluation was 23.6 years (range, 11.3 to 36 years). Standardized tests of neuropsychological functioning and QoL were performed. Descriptive statistics summarized principal findings, and one-way analysis of variance identified potential predictors of outcomes.

RESULTS

With an average follow-up time of 15 years, survivors demonstrated intellectual functioning within the low-average range. Executive functioning and verbal memory were between the low-average and borderline ranges. In contrast, visual memory and psychomotor processing speed were between the borderline and impaired ranges, respectively. Approximately 75% of patient reported overall QoL within or above normal limits for both physical and psychosocial domains. Nonhemispheric tumor location (midline or cerebellum), female sex, and younger age at treatment emerged as independent risk factors.

CONCLUSION

These results serve as a benchmark for comparison with future pediatric high-grade glioma studies, in addition to identifying at-risk cohorts that warrant further research and proactive interventions to minimize late effects while striving to ensure survival.

Neurocognitive and family functioning and quality of life among young adult survivors of childhood brain tumors

Many childhood brain tumor survivors experience significant neurocognitive late effects across multiple domains that negatively affect quality of life. A theoretical model of survivorship suggests that family functioning and survivor neurocognitive functioning interact to affect survivor and family outcomes. This paper reviews the types of neurocognitive late effects experienced by survivors of pediatric brain tumors. Quantitative and qualitative data from three case reports of young adult survivors and their mothers are analyzed according to the theoretical model and presented in this paper to illustrate the importance of key factors presented in the model. The influence of age at brain tumor diagnosis, family functioning, and family adaptation to illness on survivor quality of life and family outcomes is highlighted. Future directions for research and clinical care for this vulnerable group of survivors are discussed.

Neuropsychological differences between survivors of supratentorial and infratentorial brain tumours

BACKGROUND

The purpose of this study is to evaluate the relationship between brain tumour location and core areas of cognitive and behavioural functioning for paediatric brain tumour survivors. The extant literature both supports and refutes an association between paediatric brain tumour location and neurocognitive outcomes. We examined neuropsychological test data to identify any differences in neurocognitive and behavioural profile associated with supratentorial versus infratentorial tumour location.

METHODS

Following Institutional Review Board approval, the medical records and neuropsychological test data collected between 1997 and 2002 for 70 children treated for brain tumour at Children's Hospital Los Angeles were reviewed. Fifty-one per cent of the participants had tumours located in the supratentorial regions of the brain, whereas 49% had infratentorial tumours. Primary medical treatments involved tumour resection (90%), cranial radiation therapy (76%), chemotherapy (71%), and 59% all three medical procedures. The two tumour location groups did not differ significantly in the cumulative treatment dose of irradiation to the tumour bed or in the dose delivered to the whole brain. Neuropsychological test data included measures of verbal and non-verbal intellectual functioning, attention/working memory, processing speed, verbal and visual memory, fine motor skills, visual-motor integration, academic achievement, and social-emotional functioning. Differences between the two groups were evaluated using anova, t-tests and chi-squared statistical tests.

RESULTS

The supratentorial and infratentorial tumour location groups did not differ on measures of intellectual functioning. However, survivors of infratentorial tumours performed more poorly on selected measures of more specific cognitive functions and on parent-report of social-emotional functioning relative to survivors of supratentorial tumours, even when age at diagnosis was held as a covariate. Higher frequency of auditory deficits was noted in the infratentorial tumour group and was associated with lowered academic achievement scores.

CONCLUSIONS

The differences by location found in more specific neurocognitive and social-emotional variables, after controlling for age at diagnosis, may possibly reflect tumour location-specific effects. However, this interpretation remains tentative given the limitations in our study and inability to control for the range of medical and treatment-related factors that may have contributed towards the outcomes observed in our sample. At the same time, most of our findings appear consistent with reports from recent studies in this area.

Neurocognitive outcome 12 months following cerebellar mutism syndrome in pediatric patients with medulloblastoma

The aim is to prospectively assess early neurocognitive outcome of children who developed cerebellar mutism syndrome (CMS) following surgical resection of a posterior fossa embryonal tumor, compared with carefully matched control patients. Children who were enrolled on an ongoing IRB-approved protocol for treatment of embryonal tumors, were diagnosed with postoperative CMS, and had completed prospectively planned neuropsychological evaluation at 12 months postdiagnosis were considered eligible. The cognitive outcomes of these patients were examined in comparison to patients without CMS from the same treatment protocol and matched with regard to primary diagnosis, age at diagnosis, and risk/corresponding treatment (n = 22 pairs). Seventeen were also matched according to gender, and 14 were also matched according to race. High-risk patients received 36-39.6 Gy CSI and 3D conformal boost to the primary site to 55.8-59.4 Gy. Average-risk patients received 23.4 Gy CSI and 3D conformal boost to the primary site to 55.8 Gy. Significant group differences were found on multiple cognitive outcomes. While the matched control patients exhibited performance in the average range, patients who developed CMS postsurgery were found to have significantly lower performance in processing speed, attention, working memory, executive processes, cognitive efficiency, reading, spelling, and math. Patients treated for medulloblastoma who experience postoperative CMS show an increased risk for neurocognitive impairment, evident as early as 12 months following diagnosis. This study highlights the need for careful follow-up with neuropsychological evaluation and for obtaining critical support for patients and their families.

Students with brain tumors: their post-treatment perceptions of teachers, peers, and academics and retrospective views on school during treatment

The purpose of this pilot study was: (1) to determine how students surviving brain tumors (BTs) perceive their teachers' responses to them, their own academic performance, and their interactions with peers at school using a new measure; and (2) to describe students' retrospective perceptions of schooling while undergoing treatment. Using a sample of 22 students treated for a BT (ages 9-18) and 22 comparison (ages 8-19), no significant BT-control group differences regarding perceptions of teacher response, academic performance, and interactions with peers at school were found. Generally, students with BTs reported positive school experiences during treatment including favorable perceptions of their teachers' effectiveness, enjoyment of schoolwork, and the quality of their schooling. Additionally, they felt that completing schoolwork during treatment was important. The results of this study may provide insight into the perceived psychosocial adjustment and academic performance of students with BTs during and after treatment.

Late effects of therapy for pediatric brain tumor survivors

Approximately 2 of every 3 of all pediatric patients with brain tumors will be long-term survivors. However, there is a steep cost for pediatric brain tumor survivors, and the group as a whole faces significantly more late effects than many other survivors of pediatric cancers. Most of these effects can be attributed to direct neurologic damage to the developing brain caused by the tumor and its removal, the long-term toxicity of chemotherapy, or the effects of irradiation on the central nervous system. The late effects experienced by childhood brain tumor survivors involve multiple domains. This article will review the significant late effects that occur within the medical, neurocognitive, psychosocial, and economic domains of the survivorship experience. We conclude by discussing how the late effects in different domains often coexist and can create a complex set of obstacles that pose significant challenges for a survivor of a pediatric brain tumor on a daily basis.

Remediation of attention deficits in children: a focus on childhood cancer, traumatic brain injury and attention deficit disorder

The purpose of this review is to examine the status of attention training in children. This body of literature is very small so the review examines available efficacy studies in three paediatric groups: children who have survived cancer affecting the central nervous system (CNS) or whose treatment has impacted the CNS, children with traumatic brain injury (TBI) and children with attention deficit disorder (ADD). Seven studies/case reports are reviewed. The results are encouraging, with six of seven describing some improvement on attention measures. An original case study is presented using Pay Attention! materials with a 6 year old survivor of acute lymphoblastic leukaemia (ALL). This represents only the third report of the use of attention training materials with a survivor of childhood cancer and the first case report of the use of these materials with a very young child (6 years of age).

The effects of treatment for posterior fossa brain tumors on selective attention

We sought to identify whether deficits in selective attention are present in pediatric brain tumor patients. Selective attention was assessed with covert-orienting, filtering, and visual-search tasks in 54 patients with either (1) posterior fossa (PF) tumors treated with cranial radiation and surgery (n = 22); (2) PF tumors treated with surgery alone (n = 17); or (3) non-CNS tumors (n = 15), who served as a patient control group. To account for normal development, patient performance was also compared with that of healthy age-matched controls (n = 10). We found that in PF tumor patients selective attention was impaired, regardless of whether they were treated with cranial radiation and surgery or surgery alone. However, patients treated with cranial radiation were most impaired. These patients may have greater damage to posterior brain regions know to mediate selective attention as the result of tumor location, effects of surgery, and higher doses of radiation to the posterior regions of the brain. These findings help to elucidate the potential impact of pediatric brain tumors and their treatment on discrete attentional skills.

Neurodevelopmental impact on children treated for medulloblastoma: a review and proposed conceptual model

The population of survivors following diagnosis and treatment for medulloblastoma is thankfully on the rise. An increased focus on the quality of that survivorship has expanded the concept of cure to include efforts aimed at improving long-term cognitive outcome. It is well established in the literature that decline in overall intellect and academic performance is experienced by a majority of those undergoing treatment for pediatric medulloblastoma. This decline is believed to be secondary to decline in core cognitive abilities, which in turn are related to underlying damage to neuroanatomical substrates. A review of research on neurodevelopmental impacts following diagnosis and treatment for pediatric medulloblastoma is presented. Particular consideration is given to studies recently published that also reflect critical collaboration among those within the fields of neuropsychology and neuro-imaging. Results from the review are combined within a conceptual model upon which to guide future research and clinical efforts.

Survivors of pediatric posterior fossa tumors: cognitive outcome, intervention, and risk-based care

Adolescent and young adult survivors of posterior fossa tumors face a wide variety of functional challenges following treatment. The concept of survival needs to include plans to regularly monitor and effectively respond to those patients considered at risk for continued morbidities associated with cancer and its treatment. The nature of impairment experienced by survivors is discussed, including predominant patient- and treatment-related risk factors. A model to respond to the cognitive needs of survivors, including risk-based evaluation and intervention, is proposed. It is imperative for the success of the survivor that a team approach is taken to care. This approach must include improving the awareness and education of teachers and other education specialists who interact with this population of survivors. There is also an obligation to put forth effort in developing and validating efficacious intervention programs.

Puppets, robots, critics, and actors within a taxonomy of attention for developmental disorders

This review proposes a new taxonomy of automatic and controlled attention. The taxonomy distinguishes among the role of the attendee (puppet and robot, critic and actor), the attention process (stimulus orienting vs. response control), and the attention operation (activation vs. inhibition vs. adjustment), and identifies cognitive phenotypes by which attention is overtly expressed. We apply the taxonomy to four childhood attention disorders: attention deficit hyperactivity disorder, spina bifida meningomyelocele, traumatic brain injury, and acute lymphoblastic leukemia. Variations in attention are related to specific brain regions that support normal attention processes when intact, and produce disordered attention when impaired. The taxonomy explains group differences in behavioral inattention, hyperactivity, and impulsiveness, as well as medication response. We also discuss issues relevant to theories of the cognitive and neural architecture of attention: functional dissociations within and between automatic and controlled attention; the relative importance of type of brain damage and developmental timing to attention profile; cognitive-energetic models of attention and white matter damage; temporal processing deficits, attention deficits and cerebellar damage; and the issue of cognitive phenotypes as candidate endophenotypes.

Neurocognitive impairment in children treated for cancer: how do we measure cognitive outcomes?

As the number of childhood cancer survivors grows, more attention on the identification and management of late effects, such as neurocognitive decline, is needed. This study, investigating treatment with central nervous system (CNS) stimulants for cognitive changes related to pediatric cancer treatment, confirmed a common concern. How should neurocognitive decline be measured and followed up after cancer therapy? Multiple pediatric standardized cognitive tests are available, but there is no consensus on an efficient way to measure the most common areas of decline, specifically impaired concentration, memory, and mental processing speed. The authors' report recognized 12 pediatric patients at risk for cognitive dysfunction, of whom 3 tested positive for early neurocognitive deficits using 3 subscales of the Wechsler Intelligence Scale for Children-III (WISC-III), which measure working verbal memory (Digit Span), mental processing speed (Symbol Search), and psychomotor speed (Coding). To predict the expected level of performance on WISC-III subscales, the patients' IQ was estimated using the Wide Range Achievement Test-3 reading subtest. Patients were treated with long-acting CNS stimulants and followed up serially using the WISC-III subscales.

Parent report of attention problems predicts later adaptive functioning in children with brain tumors

Children with brain tumors are at risk for psychological and behavioral difficulties. This study examined the ability of parent report of attention problems, withdrawal, anxiety, and depression, as well as IQ, to predict later adaptive functioning in 42 children treated for brain tumors. Age at diagnosis, SES, gender, and scores on the Neurological Predictor Scale (NPS) also were examined as predictors. Parent report of attention problems, SES, and NPS were significant predictors of later adaptive functioning across domains. This finding highlights the ability of parent report of attention problems to predict later adaptive functioning in children treated for brain tumors.

Cognitive outcome in pediatric brain tumor survivors: delayed attention deficit at long-term follow-up

BACKGROUND

Treatment of childhood brain tumors has often been associated with long-term cognitive morbidity in children. Our previous research identified age at diagnosis, polytherapy and brain radiation dose as treatment factors affecting neuropsychological outcome most strongly in children with cancer 1. Our current goal was to measure the change across different cognitive functions.

PROCEDURE

This study examined the cognitive outcome over repeat testing in a heterogeneous sample of 18 children with brain tumors. Tumor types included medulloblastoma and glioma. ANOVA's for repeated measures were used to evaluate the changes in cognitive domains across follow-up evaluations.

RESULTS

Consistent with previous findings, the most deleterious effects were seen on IQ indices of non verbal cognitive ability, visual perceptual skills and information processing speed. Analyses reveal that the attentional factor, Freedom from Distractibility, is the only IQ index that declines over subsequent testing. The statistical decline was attributable to a significant decline on the arithmetic subtest, as well as a non-significant trend for the auditory attention span subtest.

CONCLUSIONS

This study reveals that while most indices remained stable over repeat testing, auditory attention and concentration skills decline. Long-term outcome is discussed in light of the high prevalence of attention and mathematic difficulties reported in these children and the need for preventive and remedial approaches.

Neurocognitive effects of treatment for childhood cancer

We review research on the neuropsychological effects that central nervous system (CNS) cancer treatments have on the cognitive abilities of children and adolescents. The authors focus on the two most common malignancies of childhood: leukemias and brain tumors. The literature review is structured so as to separate out earlier studies, generally those published prior to 1995, as opposed to manuscripts that have been published within the past decade. This is an important distinction for both leukemia and brain tumors. Earlier studies were ground breaking in that they began to map out what could be expected in terms of intelligence and academic problems in survivors of pediatric malignancies. Survivorship in this population has and continues to markedly increase and this is largely due to changes in treatment protocols. Research on neurocognitive effects of disease and treatment in pediatric oncology has become increasingly sophisticated, and this literature review not only reflects this trend, but highlights the growing collaboration between neuropsychology, cognitive neuroscience, and neuro-imaging. Thus, our goal was to provide a historical foundation, lead the reader towards the progression of research methodology up to the current state of the art, and perhaps most importantly, discuss future directions. These directions are especially relevant to the concepts of remediation and treatment of cognitive problems, and this is emphasized at the conclusion of the review.

Memory deficits in long-term survivors of childhood brain tumors may primarily reflect general cognitive dysfunctions

BACKGROUND

To analyze the impact of potential predictors on memory performance in survivors of childhood brain tumors and to examine whether deficits in memory after radiotherapy (RT) should be considered part of a more global mental dysfunction.

PROCEDURE

We studied 126 patients with brain tumors diagnosed before the age of 15 years and treated January 1970 through February 1997 in Eastern Denmark. Sixty-nine of the 126 patients had received RT. In addition to working memory and long-term memory (LTM), general intelligence (IQ) was assessed.

RESULTS

The mean test scores in nearly all memory tests were lower than expected from available norms. In multiple linear regression, treatment with RT, hemisphere tumor location, and hydrocephalus treated with a shunt at the time of diagnosis were found to be significant risk factors for memory deficits. When IQ was included as a covariate, RT did not significantly predict memory performance, while shunt and tumor location remained significant for several but not all tests.

CONCLUSION

These results suggest that in patients treated with RT, memory deficits primarily reflect a general cognitive dysfunction, and it is likely that these intelligence deficits may compromise the chances of success of special memory training. In contrast, memory deficits in non-irradiated patients may to some degree reflect specific cognitive dysfunctions being most pronounced for patients treated with a shunt and for patients with hemispheric tumors.

Prophylactic academic intervention for children treated with cranial radiation therapy

This single case study investigated the feasibility and effectiveness of a prophylactic intervention for improving academic skills in a child with a brain tumour deemed at high risk for cognitive delay and academic failure because of cranial radiation treatment (CRT). An 8 year old boy participated in a 12 week home and hospital based tutoring programme. Standardized and non-standardized measures of academic achievement were administered at pre- and post-intervention. A follow-up assessment took place 8 months post-intervention (standardized measures only). Pre-test and follow-up neuropsychological data was collected. Significant improvement was observed on the Wechsler Individual Achievement Test-2nd Edition (WIAT-II) pseudoword decoding and spelling sub-tests and on measures of single word and grapheme knowledge. There was no improvement on the WIAT-II math sub-tests. At follow-up, gains were maintained or improved for reading-related sub-tests but declined for math and spelling sub-tests. Overall, neuropsychological data showed decreased performance. The gains in reading skills were made in the context of an overall decline in neuropsychological functioning, suggesting that the intervention helped to preserve reading skills and may be protective against difficulty with skill acquisition, but did not prevent a more global decrease in functioning. This study is the first reported prophylactic intervention delivered concurrently with intensive medical treatment.

Changes in attentional performance of children and young adults with localized primary brain tumors after conformal radiation therapy

PURPOSE

To prospectively assess the impact of conformal radiation therapy (CRT) and demographic and clinical variables on four measures of attention in pediatric and young adult patients with localized primary brain tumors.

PATIENTS AND METHODS

We prospectively evaluated 120 patients with primary brain tumors, ages 2 to 24.4 years (median, 9.2 years). Evaluations were done using the computerized Conners' Continuous Performance Test (CCPT). We analyzed errors of omission (inattentiveness), errors of commission (impulsivity), reaction time, and an overall index of performance before CRT, weekly during CRT, and serially up to 60 months after the start of CRT.

RESULTS

Before CRT, patients exhibited mild inattentiveness. During CRT, impulsivity decreased significantly (P = .002). After CRT, inattentiveness increased significantly (P = .03), and global attention disorders were associated with craniopharyngioma (P < .0001), supratentorial tumors (P = .008), optic pathway and diencephalic tumors (P = .012), and subtotal resection of the tumor (P = .010).

CONCLUSION

Brain tumors and their treatment impair sustained attention and reaction time. A decline in impulsivity and relative stability of the other CCPT scores over the course of CRT demonstrated the absence of early radiation-related cognitive sequelae. Local tumor effects, initial surgical intervention, and focal irradiation of central structures contribute to long-lasting attentional problems in pediatric and young adult patients.

The Effects of Growth Hormone Treatment on Health-Related Quality of Life in Children

BACKGROUND/AIMS

The effects of growth hormone deficiency (GHD) on linear growth in children are well documented, but there is less convincing evidence regarding the impact on health-related quality of life (QOL). We examined QOL in children aged 8-16 years with acquired GHD following treatment for malignancy (AGHD) or idiopathic GHD (IGHD) on commencing growth hormone treatment (GHT) over 6 months. We adopted a longitudinal design involving consecutive patients and their families attending clinic over an 18-month period. Mothers and children were invited to complete questionnaires before GHT (T1) and 6 months later (T2).

METHODS

Mothers of 22 children (AGHD n = 14; IGHD n = 8) completed standardized measures of child QOL and behaviour. Children completed parallel measures of QOL, short-term memory tasks and fitness either in clinic or at the family home.

RESULTS

For children with AGHD, QOL was significantly below population norms at T1 and improved over time. For children diagnosed with IGHD, QOL at T1 was below, but comparable with population norms. QOL improved over time, though not significantly.

CONCLUSION

GHT is potentially valuable for improving QOL in children, especially in cases of AGHD. We conclude that benefits of GHT for QOL need to be evaluated independent of different diagnostic groups.

Early patterns of verbal memory impairment in children treated for medulloblastoma

Children treated for medulloblastoma demonstrate a variety of cognitive deficits in addition to white matter and hippocampal neuropathology. This study examined 40 children treated for medulloblastoma as compared with 40 demographically matched controls on the California Verbal Learning Test-Children's Version (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1994). Results revealed significantly poorer performance on indices of word recall in the patient group as compared with the controls in addition to milder but still significantly poorer recognition memory. These findings suggest that children treated for medulloblastoma demonstrate a mixed profile of memory impairment consisting of both retrieval and recognition deficits. Implications of these findings for understanding neurobehavioral sequelae within pediatric medulloblastoma populations and for designing educational and remediation strategies to be used with these children are discussed.

Attention and Memory Functioning Among Pediatric Patients with Medulloblastoma

OBJECTIVE

To test the hypotheses that memory and attention deficits are prevalent in survivors of childhood medulloblastoma (MB) and that these deficits are associated with problems with academic achievement.

METHODS

The medical charts of 38 child survivors of MB, who were administered the California Verbal Learning Test, Child Version (CVLT-C), Conners' Continuous Performance Test (CPT), and the Wechsler Individual Achievement Test (WIAT) as part of a comprehensive neurocognitive test battery, were retrospectively reviewed.

RESULTS

Although no significant verbal memory deficits were found, 8 of 11 CPT variables were significantly below the standardization mean (p < or = .01). Additionally, stepwise regression analyses found that increased omission errors were significantly associated with lower reading and math performance (p < or = .01).

CONCLUSIONS

These findings confirm previous reports of attention deficits among survivors of MB and provide a better understanding of how the dysfunction of particular attentional substrates (e.g., perceptual sensitivity, response bias) may result in learning problems in this population.

Implicit and Explicit Memory in Children With Congenital and Acquired Brain Disorder

Implicit and explicit memory were examined in 8- to 15-year-old children with myelomeningocele and shunted hydrocephalus, severe traumatic brain injuries, or orthopedic injuries. Each group included between 22 and 29 children. Children completed a fragmented picture identification task to assess perceptual priming and a semantic decision-making task to assess conceptual priming. Each task also assessed procedural learning as well as explicit recall and recognition. All 3 groups showed significant perceptual and semantic priming of similar magnitude. In contrast, both brain-disordered groups displayed poorer explicit memory than did the comparison group. No group showed significant procedural learning on either task. Age and IQ were stronger predictors of explicit recall than of implicit memory. The findings indicate that implicit memory is relatively intact in many children with congenital and acquired brain disorders, despite deficits in explicit memory, and support the existence of separate memory systems in children.

Change in Neurocognitive Functioning After Treatment With Cranial Radiation in Childhood

Purpose

To evaluate the pattern of stability and change over time across multiple domains of neurocognitive function in radiated survivors of posterior fossa (PF) tumors.

Patients and Methods

Thirty-four children (25 males) treated for malignant PF tumors were observed with serial clinical neuropsychologic assessments. Thirty patients were treated for medulloblastoma and four patients were treated for ependymoma. Twelve patients were treated with reduced-dose and 21 patients were treated with standard-dose cranial radiation. All patients received an additional boost to the PF. One patient was treated with PF radiation only. Standardized neuropsychologic tests were administered at different times after diagnosis for each child. The rate of change in scores was determined using a mixed model regression.

Results

Results showed a 2- to 4-point decline per year in intelligence scores. For our relatively young sample, intellectual function declined quickly in the first few years after treatment, and then more gradually. Significant declines in visual-motor integration, visual memory, verbal fluency, and executive functioning were also documented. No decline was evident for verbal memory and receptive vocabulary.

Conclusion

Cranial radiation is associated with a decline in multiple neurocognitive domains, with a few notable exceptions. Our results must be interpreted in the context of common limitations of clinical research, including patient variability, changes in test versions, small sample size, and clinical referral bias.

Developmental change and individual differences in children's multiplication

Age-related change and patterns of individual differences in children's knowledge and skill in multiplication were investigated for students in Grades 4 and 6 (approximately ages 9 and 11, respectively) by examining multiple measures of computational skill, conceptual knowledge, and working memory. Regression analyses revealed that indexes reflecting probability of retrieval and special problem characteristics overshadow other, more general indexes (problem size and frequency of presentation) in predicting solution latencies. Some improvement in the use of conceptual knowledge was evident between Grades 4 and 6, but this change was neither strong nor uniform across tasks. Finally, patterns of individual differences across tasks differed as a function of grade level. The findings have implications for understanding developmental change and individual differences in mathematical cognition.