Inclusion Criteria:

• * Histologic proof or unequivocal cytologic proof solid tumor malignancy. This may be obtained from either the primary or any metastatic site
• * Mini Mental State Examination (MMSE) ≥24
• * Age≥ 18 years
• * Karnofsky Performance Status (KPS) ≥70
• * Patient does not have metastases to the genu
• * Patient must be scheduled to undergo treatment with whole brain radiation therapy (WBRT) to manage the brain metastases
• * Patients of childbearing potential (male or female) must practice adequate contraception due to possible harmful effects of radiation therapy on an unborn child
• * Patient must have the ability to understand and the willingness to sign a written informed consent document
• * All patients must be informed of the investigational nature of this study and must be given written informed consent in accordance with institutional and federal guidelines
• * Patient must have a minimal life expectancy of at least 6 months
• * Patients receiving prior stereostatic radiosurgery (SRS) for brain metastases are eligible

Exclusion Criteria:

• * Prior WBRT
• * MMSE\<24
• * Patient has brain metastases in the genu
• * Patients must not have a serious medical or psychiatric illness that would, in the opinion of the treating physician prevent informed consent or completion of protocol treatment, and/or follow-up visits.
• * KPS\<70
• * Non-native English speakers will be excluded since patients often lose their faculty with the language they acquired second before their native language is affected in the context of cognitive decline. This could adversely affect performance on verbal cognitive tasks.
• * Patients with absolute contraindication to MRI imaging are not eligible for the study