Identify the Optimal TMS Pulse Protocol to Modulate Reward Activity

Inclusion Criteria:

1. Nicotine dependent individuals (according to the Alcohol, Smoking and Substance Involvement Screening Test nicotine dependence score).
2. Be between the ages of 18 and 55 years old.
3. Not received substance abuse treatment within the previous 30 days.
4. Be in stable mental and physical health.
5. If female, test non-pregnant.
6. No evidence of focal or diffuse brain lesion on MRI.
7. Be willing to provide informed consent.
8. Be able to comply with protocol requirements and likely to complete all study procedures.

Exclusion Criteria:

1. Contraindication to MRI (e.g., presence of metal in the skull, orbits or intracranial cavity, claustrophobia).
2. Contraindication to rTMS (history of neurological disorder or seizure, increased intracranial pressure, brain surgery, or head trauma with loss of consciousness for \> 15 minutes, implanted electronic device, metal in the head, or pregnancy).
3. History of autoimmune, endocrine, viral, or vascular disorder affecting the brain.
4. History or MRI evidence of neurological disorder that would lead to local or diffuse brain lesions or significant physical impairment.
5. Life time history of mental disorders such as: Bipolar Affective disorder (BPAD), Schizophrenia, Post-traumatic Stress disorder (PTSD) or Dementia or Major Depression.
6. uninterruptable central nervous system medication