PTH and Cognitive impairment: The neurophysiological mechanisms underlying these complaints remain unclear.<h4>Purpose</h4>To assess cortical excitability and plasticity in HypoPT patients using transcranial magnetic stimulation (TMS) and to explore the effects of parathyroid hormone (PTH) therapy on these parameters.<h4>Methods</h4>We conducted a cross-sectional study including 32 HypoPT patients on stable conventional treatment without significant cognitive impairment and 16 age-matched healthy controls.