Abstract and Introduction
Objective To assess the efficacy of cognitive interventions for children with neurological disorders, acquired brain injuries, and neurodevelopmental disorders.
Method We searched for randomized controlled trials of cognitive interventions; 13 studies met inclusion criteria. Risk of bias was rated for each study. Standardized effect size estimates were examined in 7 outcome domains. The overall quality of evidence was rated using the Grading of Recommendations Assessment, Development and Evaluation system.
Results Significant positive treatment effects were found in all outcome domains aside from inhibitory control. Effects were large for attention, working memory, and memory tasks, and small for academic achievement and behavior rating scales. Results exhibited substantial heterogeneity in all domains. Overall quality of evidence was rated very low in all domains, suggesting substantial uncertainty about effect size estimates.
Discussion The results provide some evidence of a positive benefit from cognitive interventions, but cannot be regarded as robust given the overall very low quality of the evidence.
Pediatric neurological disorders (e.g., epilepsy, brain tumors), acquired brain injuries (e.g., traumatic brain injuries), and neurodevelopmental disorders (e.g., specific learning disabilities, autistic spectrum disorder; attention-deficit/hyperactivity disorder [ADHD]) all share a common feature, which is that they are frequently associated with deficits in domain-general cognitive functions such as attention, memory, and executive functions (Ozonoff, 2010; Ris & Abbey, 2010; Westerveld, 2010; Willcutt, 2010; Yeates, 2010). Deficits in these areas are thought to help account for the functional impairments that children with such disorders display across a range of settings, including academic difficulties, behavioral problems, and social isolation. A variety of interventions have been developed to ameliorate the cognitive deficits displayed by children with central nervous system and neurodevelopmental disorders, in hopes of improving their functional outcomes. Interventions for cognitive deficits typically involve a series of sessions, with the child either interacting directly with a therapist or, in computerized home-based programs, working under the supervision of a parent or adult caretaker. The sessions typically involve instruction and practice in specific cognitive tasks, with the goal of increasing the underlying skills of attention, memory, and/or executive functions. Therapist-delivered interventions may also include specific "homework" assignments that are completed at home, in some cases with the assistance of adult caretakers or parents. The interventions vary in terms of treatment parameters, including timing (i.e., relative to onset of acute disorders), intensity (i.e., sessions per week; time spent per session), and duration (i.e., length of treatment program). The interventions also vary in their specificity, with some focusing on a single cognitive skill (e.g., working memory) and others taking a more comprehensive approach that encompasses multiple skills (e.g., metacognitive training in problem solving).
A number of systematic reviews have been published regarding cognitive interventions. Some have focused on children with neurological disorders or acquired brain injuries (Laatsch et al., 2007; McCormick, Aubut, Gnanakumar, Curiale, & Marshall, 2012; Ross, Dorris, & McMillan, 2011; Slomine & Locascio, 2009; Wolfe, Madan-Swain, & Kana, 2012) and others on children with neurodevelopmental disorders (Rapport, Orban, Kofler, & Friedman, 2013; Toplak, Connors, Shuster, Knezevic, & Parks, 2008). Some have focused on specific interventions (e.g., working memory training; Melby-Lervåg & Hulme, 2013), whereas others are more general. Most of the reviews have classified studies in terms of evidence quality, but few have involved quantitative meta-analysis. The findings from the reviews can be broadly characterized as mixed. In most cases, the reviews find evidence of short-term improvements in performance on specific cognitive tasks, but limited evidence of sustained benefits over time. Evidence of generalization of cognitive interventions to broader forms of academic, behavioral, and social functioning is less convincing than the evidence for cognitive gains.
The current review was intended to determine the efficacy of cognitive interventions for children with neurological disorders, acquired brain injuries, and neurodevelopmental disorders. The review was limited to randomized controlled trials (RCT) and other controlled clinical trials comparing cognitive interventions with an attention-only control, other active treatment, or waiting list control. Studies were eligible for inclusion only if participants were <19 years old and they had a neurological disorder, acquired brain injury, or neurodevelopmental disorder. We did not include studies of healthy children or those identified solely as intellectually disabled. Interventions needed to be primarily cognitive in nature (e.g., we excluded interventions focused on social communication in autistic spectrum disorders) and have credible recognizable cognitive content. Cognitive interventions were defined as any treatment specifically designed with the intention of improving child outcomes in attention, memory, or executive functions (e.g., working memory, inhibitory control).
The review adds to the existing literature in several regards. Perhaps most importantly, no previous review has examined the efficacy of cognitive interventions across neurodevelopmental disorders, neurological disorders, and acquired brain injuries. Given that the target of the interventions is cognitive functioning, rather than a specific diagnosis, we expected that pooling studies across disorders would provide a more robust estimate of treatment efficacy and enable a quantitative meta-analysis. The review also incorporates newer studies that do not appear in previous reviews. Additionally, the review focuses specifically on attention, memory, and executive functions, cognitive domains often considered as critical underpinnings of functional outcomes.
J Pediatr Psychol. 2014;39(8):846-865. © 2014 Oxford University Press
Copyright 2007 Society of Pediatric Psychology. Published by Oxford University Press. All rights reserved.