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.