transient, although when present, it may take years to resolve (Matsuda et al., 2005). On the other hand, the cognitive impairment associated with brain tumors and acute lymphoblastic leukemia (the most common childhood cancers) appears to be more severe and persistent, likely because of the radiation and chemotherapy specifically targeting the central nervous system that are part of the treatment protocols for these cancers and the more vulnerable condition of the rapidly developing brains of children.
Very little research has tested approaches to reducing the cognitive impairment associated with treatment for cancer8 in adults (McDougall, 2001). There is a need for well-designed longitudinal studies with baseline and ongoing measures of cognitive impairment using objective and sensitive measurement tools and approaches. These studies should also control for an array of confounding variables, such as depression, age, hormonal levels, and other treatments. Such studies would facilitate better understanding of the mechanisms, types, and severity and duration of cognitive impairment in adults, an essential precursor to the development of effective prevention, treatment, and rehabilitation interventions (Anderson-Hanley et al., 2003; Matsuda et al., 2005).
The development of services to address cognitive impairment in children has progressed somewhat further, and there is some early theoretical and empirical support for cognitive remediation, ecological or environmental interventions, and pharmacotherapy. Cognitive remediation involves identifying the patient’s specific cognitive deficits and then implementing interventions to help reduce these deficits and enable the patient to relearn through retraining and practicing salient cognitive tasks. Ecological or environmental interventions involve modifying the learning context and the methods used by the individual to acquire information and demonstrate knowledge. In school settings, for example, this could involve providing preferential seating, allowing additional time to take examinations, using true/false and multiple-choice tests rather than essay questions, and providing written handouts rather than requiring a child to copy material from the board (Butler and Mulhern, 2005). With respect to pharmacotherapy, methylphenidate, a medication used to treat children with attention-deficit disorder has shown some slight but encouraging preliminary results in children with cancer (Mulhern et al., 2004). Much more research is needed before interventions with quantified efficacy can be identified. In the interim, ecological interventions are unlikely to present significant risks to children and should be pursued; they can be included as part of school re-entry or reintegration programs, but these programs as yet have not been well
8In contrast, more research evidence exists for the effectiveness of cognitive rehabilitation in individuals with cognitive impairment due to stroke and traumatic brain injury, which is more clearly mapped and better understood (see Cicerone et al., 2005, and Tate et al., 2006).