Related Experiment Video
Updated: Jun 19, 2026

A Fine Motor Task to Study Joint Kinematics in a Preclinical Model of Neurodegenerative Disease
Published on: June 13, 2025
Semantic dementia combined with motor neuron disease
Sook Hui Kim1, Sang Won Seo, Seok Min Go
1Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong Kangnam-ku, Seoul, 135-710, Republic of Korea.
Abstract:
Up to 20% of patients with behavioural variants of frontotemporal dementia (FTD) also have motor neuron disease (MND); conversely, this comorbidity is rare in patients with language variants of FTD. A few patients have been reported with semantic dementia (SD) combined with MND. However, these patients demonstrated the clinical features of MND in the advanced stage. We report a patient with SD who also demonstrated MND symptoms in an earlier stage of the disease. A 61-year-old man visited our memory disorder clinic as a result of language disturbance and dysarthria of 8 months duration and facial recognition impairment of 3 months duration. Neuropsychological tests revealed anomic aphasia, prosopagnosia, and decreased semantic fluency. A brain MRI revealed significant atrophies localized in both anterior temporal lobes with a greater prominence on the right side. Clinical examination and electrophysiological studies confirmed a diagnosis of MND 17 months after the onset of the disease.
Related Concept Videos
Dementia l: Introduction
Parkinson's Disease: Overview
Neural Regulation
Alterations in Muscle Tone ll
Dementia
The progression of dementia is generally gradual.
Parkinson Disease ll: Pathophysiology

