Adjunctive Donepezil Therapy and Genetic Risk Factors of Cognitive Dysfunction in Brain Tumor Survivors

Patients will undergo a brief cognitive evaluation prior to (baseline/Time 1), Cognitive Re-Evaluation (about 12 weeks after Time 1), Cognitive Re-Evaluation (about 12 weeks after Time 2) ,Cognitive Re-Evaluation (about 6 months after discontinuation of Donepezil). Then pt will be tx with donepezil, an acetylcholinesterase inhibitor. They will undergo a four-week dose titration (i.e., 5mg QD during weeks 1-4) to reach a final dose of 10mg QD of oral donepezil there after for a maximum of 24 weeks.