Prospective participants with seizures will be identified primarily through the Stanford Neurology and Neuropsychiatry clinics and Stanford Medical Center, with the assistance of clinic staff and providers. Participants may also be identified and referred by their physicians in the community as well. Informational fliers will be distributed to these clinics and throughout Stanford Medical Center and Stanford campus in order to identify participants with epilepsy as well as healthy volunteers. Prospective participants may also contact study staff directly via contact information listed on the flier or provided to them by their providers. Those identified will be contacted, either in person or by telephone, by study staff.

A telephone or in-person pre-screening will occur, expected to last approximately 20-30 minutes, in order to determine eligibility for the study, interest in participating, and any questions related to the study. A brief summary of study procedures and goals will be reviewed during this pre-screening. Participants who meet inclusion/exclusion criteria may take part in an initial in-person visit at Stanford Medical Center, where informed consent will be obtained and signed (see attached informed consent form). Any additional history needed in order to confirm a participant's eligibility will be reviewed at this visit. If the individual chooses to proceed, the participant's blood pressure and heartrate will be measured, and if necessary (because a recent physical exam including cardiac auscultation is not available), a brief physical exam will be performed by a licensed physician. If vital signs and exam (if necessary) are normal, participants will be asked to complete neuropsychiatric questionnaires, self-report questionnaires, a quality-of-life questionnaire, and a seizure diary. The full 40-minute neurocognitive battery will be performed, and baseline scores obtained.

Participants will be asked to complete the seizure diary once per week, either in-person at their visits or at home. Thereafter, the participant will be asked to attend at least three additional 2-hour sessions at Stanford Medical Center. The participant will be asked to avoid taking any non-routine sedating medications within 24 hours of his/her scheduled visit, and to refrain from eating, drinking caffeine, or smoking for 2 hours prior to his/her visit. When the participant arrives, they will be given either a placebo, 20mg of methylphenidate, or 10mg of methylphenidate (randomized and blinded by the research pharmacy), and asked to remain within the hospital for 1 hour prior to testing to allow the medication to enter their system. Both study staff and the participant will be blinded to whether they are receiving active medication or placebo. During this time, the participant will complete self-report questionnaires reporting any medication changes, medical events, or significant adverse events, and their seizure diary will be reviewed and kept by study staff. After this, the full neurocognitive battery will be completed. Following the completion of neurocognitive testing, the participant's next visit will be scheduled for approximately the same time of day in approximately one week, and payment will be provided. This procedure will be repeated for the next two visits. Participants will not receive any additional study drug during this period other than the single dose they receive in-person.

At the participant's fourth visit, they will be asked to repeat the neuropsychiatric questionnaires from visit #1, as well as the usual self-report forms and seizure diary. Heartrate and blood pressure will be obtained again prior to the administration of the neurocognitive battery. At the end of the fourth visit, participants will be asked if they wish to take part in the four-week open-label phase of this study, designed to evaluate the ongoing efficacy and safety of methylphenidate for use in patients with epilepsy. Regardless of their answer, payment will be provided for their fourth visit.

Those participants who are interested in participating in the open-label trial will be provided with a prescription for two weeks of methylphenidate 10mg PO BID, followed by two weeks of methylphenidate 20mg PO BID. Participants will be provided with copies of the seizure diary and asked to complete it weekly. Participants will be able to contact the protocol director by phone to report any significant side effects or adverse events during this trial. At the protocol director's discretion, in keeping with standard of care for this medication, the dosage of the medication may be lowered (minimum dose 5mg PO BID) in response to any side effects experienced by participants during this period.

Participants in the open-label trial will be asked to return after four more weeks for a fifth and final visit. Participants will again be asked to refrain from eating, caffeine, and nicotine for 2 hours prior to their visit, and will take their prescribed methylphenidate upon arriving at Stanford Medical Center. Participants will wait 1 hour for the medication to enter their system, during which time they will complete neuropsychiatric and self-report questionnaires as before, their seizure diaries will be reviewed, and their heart rate and blood pressure will again be measured. The cognitive battery will be administered again. Afterwards, any participant questions will be answered and final financial compensation will be provided, and the participant's involvement has ended. Data will remain blinded until the completion of the study. Participants wishing to receive the active medication following the termination of the open-label phase of the study may do so at the discretion of their physicians.