Background Akinetic Mutism (AM) is a clinical condition of lacking of almost all motor functions including speech, gestures, and facial expression.1 Two subtypes of AM are distinguished. Apathetic AM involves mesencephalic and diencephalic regions, whereas hyperpathic AM is associated to anterior cingulate gyrus and adjacent frontal lobes.2 AM has been observed in different pathological conditions, but it has never been described in Huntington’s disease (HD), a neurodegenerative disease caused by cytosine-adenine-guanine (CAG)-repeat expansion in the huntingtin gene.
Case History We described AM in T.A., a 27-year-old Ukrainian male with genetically confirmed HD. T.A. developed HD symptoms in his late teenage years with likely juvenile onset of the disorder. PET scan showed reduced FDG uptake in bilateral striatum and in bilateral frontal and parietal regions. We assessed AM in T.A. with dedicated tasks, in addition to a neuropsychological examination to explore cognitive abilities. Neuropsychological examination showed poor performances on inhibitory control skills, selective and sustained attention abilities, and on anterograde verbal memory tasks. Moreover, T.A. showed diminished motivation with preserved consciousness level and inability to respond to auditory or visual commands.
Conclusions Our findings would be consistent with the hypothesis that hyperpathic AM in T.A. is related to frontal/executive dysfunctions, and would contribute to refine the hyperpathic AM in HD.
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- Akinetic Mutism
- Neuropsychological assessment