Transcutaneous Auricular Neurostimulation (tAN) for Premenstrual Dysphoric Disorder (PMDD) and Perimenopause

Transcutaneous Auricular Neurostimulation (tAN) will be administered to women with premenstrual syndrome (PMS), premenstrual dysphoric disorder (PMDD), and perimenopause. The investigators will examine whether tAN improves symptomology by collecting self-report data before the intervention, during the intervention, and following the intervention.

PMS/PMDD Study: Inclusion Criteria: * Assigned female at birth * Age 18 to 45 * Naturally cycling * Regularly occurring menstrual cycle * Must identify as having PMS or PMDD * Reliable ability to complete online study surveys Exclusion Criteria: * Using hormonal birth control * Pregnant or lactating/breastfeeding * History of seizures * Implanted devices * Current or previous diagnosis of any heart conditions * Abnormal ear anatomy * Non-removable piercings on the ear * Recent ear infection * Taking SSRIs * Taking steroids * Taking hormone therapy * If the participant anticipates starting or stopping prescription medications during the study period * Participant has a history of neurologic diseases (i.e. stroke, brain tumor, cerebrovascular, etc.) * Participant has a history traumatic brain injury within the past 12 months * Must not have any other mental illness or mood disorder Perimenopause Study: Inclusion Criteria: * Assigned female at birth. * Age 40 to 55 * Must have newly variable menstrual cycles or report identifying as perimenopausal * Reliable ability to complete online study surveys Exclusion Criteria: * Using hormonal birth control * Pregnant or lactating/breastfeeding * History of seizures * Implanted devices * Current or previous diagnosis of any heart conditions * Abnormal ear anatomy * Non-removable piercings on the ear * Recent ear infection * Taking SSRIs * Taking steroids * Taking hormone therapy * If the participant anticipates starting or stopping prescription medications during the study period. * Participant has a history of neurologic diseases (i.e. stroke, brain tumor, cerebrovascular, etc.) * Participant has a history traumatic brain injury within the past 12 months * have a hysterectomy In both studies we will confirm that participants are symptomatic shortly following enrollment.