Use of Transcranial Photobiomodulation to Improve Cognition and Self-Reported Outcomes in Survivors of Childhood Cancer

Inclusion Criteria: * Completed treatment for acute lymphoblastic leukemia (ALL) or Hodgkin's Lymphoma (HL) at SJCRH. * Enrolled in SJLIFE, and less than 21 years of age at diagnosis. * 18 years of age or older at time of enrollment. * 2 years or greater post-treatment completion of cancer directed therapy and not currently receiving any cancer directed therapy. * English language proficiency. * Access to WiFi. * Executive dysfunction defined as having an age-adjusted standard score less than 16th percentile on objectively assessed cognitive test or patient-reported executive dysfunction defined as having a standard score greater than 84th percentile within 3 years of time of enrollment. Exclusion Criteria: * Estimated intelligence score less than 80. * Currently taking medication intended to treat neurocognitive impairment (i.e., stimulants). * Major psychiatric condition. * Alcohol abuse in the past year (AUDIT) \[greater than or equal to 13 for women and greater than or equal to 15 for men\]. The Alcohol Use Disorders Identification Test (AUDIT) will be used to screen for individuals who have active alcohol-use disorders. * Drug abuse in the past year (DAST-10) \[ greater than or equal to 3 for women or men\] The Drug Abuse Screen Test (DAST-10) will be used to screen for individuals with active drug abuse. * History of neurologic condition or genetic disorder associated with neurocognitive impairment unrelated to cancer diagnosis or treatment. * Enrolled on another independent cognitive intervention protocol within the last year. * Female participants who are pregnant or lactating (determined by participant self-report due to the remote nature of this study) * Tattoo or artificial marking in the area where the device will be positioned.