This is a multicenter pilot randomized controlled trial, with an active control condition, of the feasibility, acceptability, and preliminary efficacy of EndeavorRx in a cohort of survivors of acute lymphoblastic leukemia or brain tumor ages 8-16 who are > 1 year from the end of therapy.

Survival rates are increasing for common pediatric cancers, including acute lymphoblastic leukemia (ALL) and brain tumors; yet, the life-saving treatments for these cancers place survivors at heightened risk for sustained cognitive effects. Longitudinal research has shown that the cognitive burden of ALL and pediatric brain tumors often consists of impairments in attention, working memory, and executive functioning, which can result in long-term disruption to daily living, socialization, academic achievement, and quality of life. Few non-pharmacological interventions exist to ameliorate these cognitive late effects. EndeavorRx, an FDA-approved electronic attentional-control training program, may be one intervention to help remediate executive functioning difficulties experienced by survivors. Although the program has been efficacious for youth with Attention-Deficit/Hyperactivity Disorder (ADHD), it has not yet been tested among survivors of childhood ALL or brain tumor. We propose to assess the feasibility, acceptability, and preliminary efficacy of EndeavorRx in a pilot randomized, controlled trial. Survivors of ALL or brain tumor who are between the ages of 8 and 16 and have been off-therapy for at least one year will be included. The goal is to enroll and screen approximately 50 survivors across three pediatric oncology centers, in order to identify 40 participants with attention difficulties who will be randomized to one of two treatment arms. Participants will be assigned to either the EndeavorRx intervention, which includes 25-30 minute sessions per day, 5 days per week, for one month, or an active control condition of the same duration and intensity. Patients will undergo neurocognitive testing pre- and post-intervention, and parents will complete questionnaires regarding their child's functioning. It is hypothesized that this attentional-control training program will be both acceptable and feasible, with sufficient enrollment, positive satisfaction ratings, and acceptable treatment adherence. It is also anticipated that participants will show increases in performance-based and parent-rated attention, as compared to those in the active control condition.

Inclusion Criteria:

• Aged 8-16 years at time of screening.
• History of diagnosis of acute lymphoblastic leukemia (ALL) or brain tumor (BT).
• At least 1 year from completion of planned therapy and stable from a disease standpoint.
• Participating child and caregiver are fluent in spoken English.
• Availability of a caregiver who is willing and capable of providing support and supervision during cognitive training.
• Participating child is either not taking any prescribed stimulant medication for attention difficulties or has been prescribed a stable dose of stimulant medication for attention difficulties for at least 30 days prior to enrollment.
• Only patients with a T-score ≥ 75th percentile on the CPT-3 Omission Errors scale or on the BRIEF-2 Cognitive Regulation Index will be randomized.

Exclusion Criteria:

• A history of photosensitive seizures.
• A motor, visual, or auditory handicap that prevents computer use.
• A mental health condition that precludes, or takes treatment precedence over, participation in the cognitive training.
• Participants identified during the baseline assessment as having a full-scale IQ < 80, as estimated by WASI-II (Vocabulary and Matrix Reasoning), will not be randomized.