Multimodality evoked potentials in sporadic amyotrophic lateral sclerosis: a statistical approach.

The involvement of sensory pathways in patients suffering from amyotrophic lateral sclerosis (ALS) is well reported in histopathological studies. Several laboratories have also used evoked potentials to evidentiate subtle dysfunctions of sensory systems in such patients. However, conflicting results have been presented in studies using evoked potentials. In the present experiment we have evaluated multimodality evoked potentials in subjects with sure diagnosis of sporadic ALS, by means of the Bonferroni multiple comparisons procedure. Our principal findings are: a) no statistical difference between patients and controls in BAEP and VEP recordings; b) a reduction of N13 amplitude and a prolonged P22 latency in SEP recordings. Due to the sources of N13 and P22, these latter alterations, however, do not implicate the involvement of somatosensory pathway. In conclusion, the current investigation does not provide an electrophysiological support for the involvement of sensory systems in the sporadic ALS.