Effects of Chemotherapy on the Brain in Women With Newly Diagnosed Early-Stage Breast Cancer

DISEASE CHARACTERISTICS: * Diagnosis of breast cancer, meeting 1 of the following criteria: * Group A * Stage I, II, or III invasive disease * Hormone receptor-positive disease * Planned adjuvant chemotherapy including an anthracycline and taxane using either dose-dense or docetaxel, doxorubicin hydrochloride, and cyclophosphamide (TAC) regimens with or without trastuzumab (Herceptin®) for 4 months; docetaxel and cyclophosphamide (TC) with or without trastuzumab for 3 months; doxorubicin hydrochloride and cyclophosphamide (AC) for 3 months; or doxorubicin hydrochloride, carboplatin, and trastuzumab (TCH) for 4 months (trastuzumab may be given for 1 year and is not considered chemotherapy for the purpose of this study) * Planned treatment with adjuvant aromatase inhibitors (AI) for 5 years * Group B * Stage I or II invasive disease * Planned treatment with adjuvant AI with or without radiotherapy * Group C * Stage I, II, or III disease * Hormone-receptor negative * Planned adjuvant chemotherapy as in group A * No treatment with AI planned * Group D * Healthy controls free of any major medical or psychiatric disorders * Not taking prescription medications, including hormone-replacement therapy, or other substances that might influence performance on neuropsychological tests * Balanced with the patient groups on age, education, ethnicity, and sociodemographic background PATIENT CHARACTERISTICS: * No history of psychiatric illness other than minor depression * No history of psychiatric illness other than minor depression in immediate family members * No history of neurologic disease * No history of drug or alcohol abuse * No significant medical illness other than breast cancer * No heart pacemaker or metallic implants or particles in the body * No heart rhythm disturbance * No claustrophobia * No prior serious head injury * No tattoos or permanent cosmetics * No unremovable body jewelry * No cognitive impairment * Able to read and speak English * No condition that compromises compliance with the objectives and procedures of this study, as judged by the principal investigator PRIOR CONCURRENT THERAPY: * See Disease Characteristics * No prior chemotherapy, CNS radiotherapy, or intrathecal therapy * Premenopausal women receiving aromatase inhibitors must also be receiving ovarian suppression * No concurrent narcotics or major antipsychotic medications that may impair cognition