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Background Performance validity tests (PVTs) and symptom validity tests (SVTs) are essential to neuropsychological evaluations, helping ensure findings reflect true abilities or concerns. It is unclear how PVTs and SVTs perform in children who received radiotherapy for brain tumors. Accordingly, we investigated the rate of noncredible performance on validity indicators as well as associations with fatigue and lower intellectual functioning. Methods Embedded PVTs and SVTs were investigated in 98 patients with pediatric craniopharyngioma undergoing proton radiotherapy (PRT). The contribution of fatigue, sleepiness, and lower intellectual functioning to embedded PVT performance was examined. Further, we investigated PVTs and SVTs in relation to cognitive performance at pre-PRT baseline and change over time. Results SVTs on parent measures were not an area of concern. PVTs identified 0–31% of the cohort as demonstrating possible noncredible performance at baseline, with stable findings 1 year following PRT. Reliable digit span (RDS) noted the highest PVT failure rate; RDS has been criticized for false positives in pediatric populations, especially children with neurological impairment. Objective sleepiness was strongly associated with PVT failure, stressing need to consider arousal level when interpreting cognitive performance in children with craniopharyngioma. Lower intellectual functioning also needs to be considered when interpreting task engagement indices as it was strongly associated with PVT failure. Conclusions Embedded PVTs should be used with caution in pediatric craniopharyngioma patients who have received PRT. Future research should investigate different cut-off scores and validity indicator combinations to best differentiate noncredible performance due to task engagement versus variable arousal and/or lower intellectual functioning. [ABSTRACT FROM AUTHOR]

Cerebellar mutism syndrome is a disorder of speech, movement and affect that can occur after tumour removal from the posterior fossa. Projections from the fastigial nuclei to the periaqueductal grey area were recently implicated in its pathogenesis, but the functional consequences of damaging these projections remain poorly understood. Here, we examine functional MRI data from patients treated for medulloblastoma to identify functional changes in key brain areas that comprise the motor system for speech, which occur along the timeline of acute speech impairment in cerebellar mutism syndrome. One hundred and twenty-four participants, all with medulloblastoma, contributed to the study: 45 with cerebellar mutism syndrome, 11 patients with severe postoperative deficits other than mutism, and 68 without either (asymptomatic). We first performed a data-driven parcellation to spatially define functional nodes relevant to the cohort that align with brain regions critical for the motor control of speech. We then estimated functional connectivity between these nodes during the initial postoperative imaging sessions to identify functional deficits associated with the acute phase of the disorder. We further analysed how functional connectivity changed over time within a subset of participants that had suitable imaging acquired over the course of recovery. Signal dispersion was also measured in the periaqueductal grey area and red nuclei to estimate activity in midbrain regions considered key targets of the cerebellum with suspected involvement in cerebellar mutism pathogenesis. We found evidence of periaqueductal grey dysfunction in the acute phase of the disorder, with abnormal volatility and desynchronization with neocortical language nodes. Functional connectivity with periaqueductal grey was restored in imaging sessions that occurred after speech recovery and was further shown to be increased with left dorsolateral prefrontal cortex. The amygdalae were also broadly hyperconnected with neocortical nodes in the acute phase. Stable connectivity differences between groups were broadly present throughout the cerebrum, and one of the most substantial differences—between Broca's area and the supplementary motor area—was found to be inversely related to cerebellar outflow pathway damage in the mutism group. These results reveal systemic changes in the speech motor system of patients with mutism, centred on limbic areas tasked with the control of phonation. These findings provide further support for the hypothesis that periaqueductal grey dysfunction (following cerebellar surgical injury) contributes to the transient postoperative non-verbal episode commonly observed in cerebellar mutism syndrome but highlights a potential role of intact cerebellocortical projections in chronic features of the disorder. [ABSTRACT FROM AUTHOR]

Pediatric cancer treatment, especially for brain tumors, can have profound and complicated late effects. With the survival rates increasing because of improved detection and treatment, a more comprehensive understanding of the impact of current treatments on neurocognitive function and brain structure is critically needed. A frontline medulloblastoma clinical trial (SJMB03) has collected data, including treatment, clinical, neuroimaging, and cognitive variables. Advanced methods for modeling and integrating these data are critically needed to understand the mediation pathway from the treatment through brain structure to neurocognitive outcomes. We propose an integrative Bayesian mediation analysis approach to model jointly a treatment exposure, a high‐dimensional structural neuroimaging mediator, and a neurocognitive outcome and to uncover the mediation pathway. The high‐dimensional imaging‐related coefficients are modeled via a binary Ising–Gaussian Markov random field prior (BI‐GMRF), addressing the sparsity, spatial dependency, and smoothness and increasing the power to detect brain regions with mediation effects. Numerical simulations demonstrate the estimation accuracy, power, and robustness. For the SJMB03 study, the BI‐GMRF method has identified white matter microstructure that is damaged by cancer‐directed treatment and impacts late neurocognitive outcomes. The results provide guidance on improving treatment planning to minimize long‐term cognitive sequela for pediatric brain tumor patients. [ABSTRACT FROM AUTHOR]

The prefrontal cortex modulates executive control processes and structurally matures throughout adolescence. Consistent with these events, prefrontal functions that demand high levels of executive control may mature later than those that require working memory but decreased control. To test this hypothesis, adolescents (9 to 20 years old) completed nonverbal working memory tasks with varying levels of executive demands. Findings suggest that recall-guided action for single units of spatial information develops until 11 to 12 years. The ability to maintain and manipulate multiple spatial units develops until 13 to 15 years. Strategic self-organization develops until ages 16 to 17 years. Recognition memory did not appear to develop over this age range. Implications for prefrontal cortex organization by level of processing are discussed.

Healthy adolescents (79 girls, 66 boys), ages 9-17, completed the Iowa Gambling Task (IGT; A. Bechara, A. R. Damasio, H. Damasio, & S. W. Anderson, 1994) as well as working memory (digit span) and behavioral inhibition (go/no-go) tasks. Cross-sectional age-related changes were seen on all 3 tasks. Gender differences were seen in IGT deck preference and attentional variables (i.e., go/no-go hit rate and forward digit span). After age, gender, and general intellectual abilities were controlled for, IGT performance was not predicted by working memory or behavioral inhibition scores. Findings suggest that the ventromedial prefrontal cortex or its connections are functionally maturing during adolescence in a manner that can be distinguished from maturation of other prefrontal regions. Development of these functions may continue into young adulthood.

Craniopharyngioma is a histologically benign brain tumor that arises in the suprasellar region affecting critical neurovascular structures including the hypothalamic-pituitary-adrenal axis and optic pathways. Children with craniopharyngioma often experience excessive daytime sleepiness (EDS) which may be compounded by anxiety and depression. The current study investigated disparate sleep profiles to better understand psychological adjustment among children diagnosed with craniopharyngioma. Method: Actigraphs recorded nightly sleep data, including measures of sleep onset latency (SOL) and wake after sleep onset (WASO), in a cohort of 80 youth between the ages of 2 and 20 years (median age = 9). Parent reports of behavioral and emotional functioning were included in the analysis. A latent profile analysis examined disparate sleep profiles, and a multinomial logistic regression examined differences of anxiety and depression among the sleep profiles. Results: The latent profile analysis revealed three sleep profiles: "healthy sleepers" (68.8%), "night wakers" (21.3%), and "prolonged onset sleepers" (10.0%). Contrary to expectations, sleep profiles were not associated with daytime anxiety (β = 2.26–4.30, p >.05) or depression (β = −5.87–4.74, p >.05). Conclusions: Youth with craniopharyngioma demonstrate poor sleep and EDS. Those with delayed SOL and prolonged WASO are particularly vulnerable to disrupted nighttime sleep, which may significantly compound EDS. Disrupted sleep was not associated with anxiety or depression, which may be related to the overall poor sleep and daytime sleepiness or to timing, as patients were early in their treatment course. Further study should evaluate the factors underlying sleepiness and daytime function in patients with craniopharyngioma. [ABSTRACT FROM AUTHOR]

Objectives: Psychosocial late effects among survivors of pediatric brain tumors are common. For school-aged survivors, social skills deficits and isolation present a particular challenge. Social problem-solving is a social skill that is an important determinant of social outcomes and may yield a potential target for intervention.Methods: School-aged youth (N = 65) 8-12 years of age (10.59 ± 1.36 years; 55.4% female, 86.2% white) who were 5.23 (SD = 2.44, range 2-10.9) years post-treatment for a brain tumor completed the Attributions and Coping Questionnaire, a measure of social problem-solving that uses vignettes to assess attribution of intent, subsequent emotional response, and imagined behavioral response to an interpersonal problem. Youth also completed self-reports of social functioning (PROMIS Peer Relationships, Self-Perception Profile). A caregiver completed additional measures of child social functioning (NIH Toolbox-Emotion Measures).Results: Survivors attributed unpleasant situations to accidental causes (neutral attribution) and responded in ways that prioritized the friendship (appeasement) or relied on adult intervention. Self-reported social functioning was higher among those who were less likely to avoid challenging social problem-solving situations.Conclusions: Findings identified characteristic social problem-solving approaches among survivors, including a tendency to attribute ambiguous situations to accidental causes and to request adult assistance and/or maintain social relationships. This may indicate a possible avenue for intervention, with a focus on increasing survivors' understanding of the causes of potentially negative peer interactions and reducing their reliance on adults. [ABSTRACT FROM AUTHOR]