Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 8 3 2013 09 15 149 51 Esmaeel Ghoreishi Department of Neurology, Ardebil University of Medical Sciences, Ardebil, Iran Gholam Ali Shahidi Department of Neurology, Iran University of Medical Sciences, Tehran, Iran Mohammad Rohani Department of Neurology, Iran University of Medical Sciences, Tehran, Iran Mohammad Nabavi Department of Allergy and Immunology, Iran University of Medical Sciences, Tehran, Iran Mahbubeh Aghaei Iran University of Medical Sciences, Tehran, Iran Fahimeh Haji Akhoundi Iran University of Medical Sciences, Tehran, Iran 2015 10 14 Objective: Hashimoto encephalopathy (HE) is known as a steroid-responsive encephalopathy associated with autoimmune thyroiditis or nonvascular inflammation-related autoimmune meningoencephalitis. The average age of onset of HE is approximately 50 years; and it is more common in women. The onset of HE may be acute or subacute. The course of most HE cases is relapsing and remitting, which is similar to that of vasculitis and stroke. Methods: In this article, we present a previously healthy 32 years old; veterinarian male with palatal myoclonus, as a rare presentation of this disorder, and review the neurologic aspects of hashimoto encephalitis . Results: The clinical presentation of HE is characterized by progressive cognitive decline tremor, transient aphasia, seizures, abnormal gait, sleep disorder and stroke-like episodes . Myoclonus, either generalized or multifocal, and tremor, often of the bilateral upper extremities, is the most frequently observed involuntary movements in HE. Conclusion: The rapidly progressive cognitive dysfunction and encephalopathies observed. https://ijps.tums.ac.ir/index.php/ijps/article/view/119 https://ijps.tums.ac.ir/index.php/ijps/article/download/119/115