Brain Function in Young Patients Receiving Methotrexate for Acute Lymphoblastic Leukemia

Inclusion Criteria: * Diagnosis of acute lymphoblastic leukemia * Enrolled on COG-AALL0434 (Cohort #1 only) or COG-AALL0232 (Cohorts #1 and #2) * Patients must have received either high-dose methotrexate or escalating-dose methotrexate during interim maintenance. * No CNS-3 disease * Patients must enroll within 8-24 months after completion of therapy on COG-AALL0232 and no evidence of relapsed or secondary malignancy * No known significant neurodevelopmental disability unrelated to cancer diagnosis including, but not limited to, any of the following: * Down syndrome * Fragile X mental retardation * Autism * Pervasive developmental disability * Seizure disorder * Attention-deficit hyperactivity disorder or specific learning disability (e.g., dyslexia) allowed * No sensory impairment (e.g., pre-existing uncorrectable vision impairment or deafness) * No cranial radiation therapy