Circuit-Guided Neuromodulation for Anorexia Nervosa

The goal of this clinical trial is to find out whether personalized, non-invasive brain stimulation can temporarily change communication within brain networks related to restrictive eating in adults with anorexia nervosa. The main questions this study aims to answer are: * Does personalized transcranial magnetic stimulation (TMS) change functional connectivity within a brain network related to restrictive eating compared with sham stimulation? * Do different types of TMS affect measures related to inhibitory control, body image, eating-disorder symptoms, mood, and anxiety, and are they safe and well tolerated? Participants will: * Attend four study visits, separated by at least one week. * Complete clinical and psychological assessments and undergo brain magnetic resonance imaging (MRI). * Receive three stimulation conditions in random order at separate visits: intermittent theta-burst stimulation (iTBS), continuous theta-burst stimulation (cTBS), and sham stimulation. * Complete brain MRI scans and research tasks so that the effects of the three stimulation conditions can be compared. Researchers will compare the effects of iTBS and cTBS with sham stimulation on brain connectivity and other study measures. This is an exploratory proof-of-concept study designed to test whether personalized brain stimulation can engage the targeted brain circuit. It is not designed to determine whether TMS is an effective treatment for anorexia nervosa, and direct clinical benefit to participants is not expected.

Inclusion Criteria: * Age between 18 and 65 years, inclusive. * Established diagnosis of anorexia nervosa according to DSM-5 criteria, confirmed by the Structured Clinical Interview for DSM-5 (SCID-5) at Visit 1. * Capacity to provide written informed consent, as assessed by the investigator at Visit 1. * Fluency in European Portuguese sufficient to complete the study assessments. Exclusion Criteria: * Current manic or psychotic episode. * Major or minor neurocognitive disorder. * Neurodevelopmental disorder, including attention-deficit/hyperactivity disorder (ADHD) or autism spectrum disorder (ASD). * Any medical or psychiatric condition requiring immediate hospitalization at the time of enrollment. Psychiatry day hospital care does not constitute an exclusion criterion. * History of a structural lesion of the central nervous system. * Presence of electrical or metallic implants incompatible with TMS or MRI, including cochlear implants, deep brain stimulators, vagus nerve stimulators, cardiac pacemakers, implantable cardioverter-defibrillators, intracardiac lines, or aneurysm clips or coils, in accordance with the manufacturer's contraindications. * Personal history of epilepsy or unexplained loss of consciousness. * Any contraindication to TMS or MRI. * Pregnancy or breastfeeding at the time of enrollment. * For participants of childbearing potential, lack of use of an effective method of contraception throughout the study period.