Open Label Extension Study of tDCS Plus Guided Imagery for Women With Chronic Pelvic Pain (CPP)

Inclusion Criteria: * Study participants must have participated and completed: (IRB 2019-362) A Multi-Stage, Randomized, Single Blind, Pilot study of the Acute Effects of Guided Imagery and Transcranial Direct Current Stimulation (tDCS) on EEG Alpha Brain Waves and Pain Levels in Women with Chronic Pelvic Pain, referred to as Part * Female * Age 18 to 64 years * Women must either be unable to become pregnant (are surgically sterile or postmenopausal) or must use an approved method of birth control throughout the study period. * Self-reported CPP defined as pelvic pain that is non-cyclical and of at least 6 months duration and refractory to other treatments * Subject agrees to not start any new treatment (medication or otherwise) throughout the treatment and follow up periods. * Subject agrees to maintain stable doses of all current medications throughout the treatment and follow-up period. Exclusion Criteria: * History of seizures during the last 2 years or diagnosis of epilepsy * Pacemaker * Currently using tobacco * Use of carbamazepine, oxcarbazepine, phenytoin, pramipexole or cabergoline within the past 6 months as self-reported * Parkinson's Disease * Any condition, including neurological or psychiatric illness, which per investigators' judgement may increase subject risk * History of Hunner's lesions * Lactation, pregnancy, or refusal to use medically approved/reliable birth control in women of child-bearing potential * Sacral or pudendal Interstim® or spinal cord stimulator that is "on" * Contraindications to tDCS stimulation (e.g. metal in the head, implanted brain medical devices, scalp wounds or infections, etc) * History of head injury resulting in more than a momentary loss of consciousness during the last 2 years Deferral Criteria 1. If a subject has a confirmed UTI per investigator's clinical judgment, she will be deferred until treatment is completed and symptoms resolve 2. Participating in another intervention study, or received an investigational drug or device within 4 weeks prior to screening 3. Subject received bladder hydrodistention within the past 12 weeks 4. Within the past four weeks, initiation of any new medications or any intravesical treatment for treatment of IC/BPS. 5. Within the past 24 weeks received any surgery or procedure which may impact the pelvic floor * Note: For the sake of preserving scientific integrity, one of more of the eligibility criteria have been left off this list posting while the trial is ongoing. A full list of eligibility criteria will be posted upon completion of the trial.