Treatment of Post-Chemo Cognitive Impairment w/Transcranial Magnetic Stimulation (Chemobrain TMS)

In this pilot study, the investigators propose to test the efficacy of rTMS for the treatment of PCCI. Efficacy measures will include baseline and post-rTMS neuropsychological testing, functional MRI and biometry data using body worn sensors.

Transcranial magnetic stimulation (TMS) is a safe and non-invasive brain stimulation technique. It uses a magnetic coil to stimulate brain tissue painlessly using only a magnet (no electrodes or electrical wires) in a procedure that does not involve any surgery or sedation. TMS is currently FDA approved to treat depression and migraines. Although this technology is applicable to many other brain conditions as well, it has not been systematically examined in individuals with "Chemo-brain". Chemo-brain or Post-Chemotherapy Cognitive Impairment (PCCI) is defined as cognitive changes including impairment of memory, learning, concentration, reasoning, executive function, attention and visuo visio-spatial skills that occur during or after chemotherapy treatment.

In this study, investigators will:

1. use high-resolution magnetic resonance imaging (MRI) of individuals' brains to determine precisely where to place the TMS magnetic coil in order to stimulate the target brain region based off their unique brain structure.
2. use TMS to stimulate the target region of the brain.
3. take high-resolution MRI pictures of the brain both baseline and post-TMS to study whether the brain activity of the target region changes as a result of the TMS stimulation.
4. perform neuropsychological tasks baseline and post-TMS to study if performance is improved following stimulation of the target brain region.
5. collect data from completing Frailty assessments, baseline and post-TMS.
6. study the short-term and long-term treatment effects.
7. collect subject's daily activity and sleep/wake patterns from watch style device (http://www.actigraphy.com/solutions/actiwatch/actiwatch-plus-specifications.html).
8. perform behavioral assessments, baseline and post-TMS, to study whether there are measurable changes following stimulation of the target brain region.

Eligibility Criteria:
Inclusion Criteria:

* Adult (\>=18).
* PCCI diagnosis (see information below).
* Right Handed (We will not enroll left-handed dominant people because they tend to have more symmetric brain function and thus targeting the left frontal region may not be as effective.)
* English speaking.
* Cancer treatment completed and considered curative with the exception of endocrine therapy after chemotherapy.
* Able to attend daily intervention (Monday-Friday) for 2 weeks.
* Not enrolled in another interventional study within 6 months prior to beginning this study.

Exclusion Criteria:

* Pregnancy or thinking of becoming pregnant.
* Undergoing active treatment for cancer.
* Routine contraindications for MRI (including incompatible medical implants or metal fragments in the body at risk for migration or heating with application of the magnetic field) including severe claustrophobia.
* History of brain metastasis or other brain tumor.
* History of stroke or traumatic brain injury.
* Frequent or severe headaches.
* Cognitive or mood disorder prior to chemotherapy (i.e. dementia or depression).
* History of epilepsy, or other seizure disorders.
* History mental health disorders, such as substance misuse, bipolar disorder or psychosis.
* Taking medication for seizures or that could lower seizure threshold if withdrawn.
* Inability to complete neuropsychological testing.
* Prior treatment with rTMS. We will enroll subjects without prior experience with rTMS.