Complex cognitive disruption in motor neuron disease.

We describe 14 patients having been diagnosed as suffering from motor neuron disease (MND). These patients underwent a detailed and sequential neuropsychological evaluation, with particular care of neurolinguistic assessment. Their results have been compared to those obtained by a group of healthy volunteers. The most obvious disclosure was the finding of 4 cases of frontal dementia in the MND group. Apart from that, we demonstrated subtle though evident frontal disruption signs, evidenced by an alteration in language planning, language comprehension, morphosyntactic operations, planning, attention deficit, and abstract reasoning disturbances which got worse during the 15 months of follow-up in all the other subjects. We suggest that a specific and sensitive neurolinguistic and neuropsychological test battery could detect signs of disruption of cognition present even in the sporadic form of MND. We discuss the results with a review of the literature.