[Cognitive evoked potentials in remitting-relapsing and benign forms of multiple sclerosis]

The assessment of the cognitive impairment in the multiple sclerosis disease is one of the most relevant challenges nowadays. An essential objective is to obtain diverse approaches that allow valuing objectively this impairment and its correlation with physiological variables.

To analyze the possible modulations in physiological components of the information processing (ERPs) related with an attentional deficit in diverse classes of patients with multiple sclerosis.

17 patients with remitting-relapsing multiple sclerosis, 9 patients with benign multiple sclerosis and 19 healthy subjects participated in the study. Behavioral performance in a visuo-spatial task (Posner paradigm) and later, an auditory oddball test was carried out where electroencephalography signal was registered to obtain ERPs. Correlation analyses were calculated between patient variables (EDSS or disease duration) and psychophysiological variables.

A delay in the reaction time during the development of the Posner task and a delay in the latency of the component P3 during the realization of the oddball task were found in both groups of patient with multiple sclerosis.

The data obtained in this experiment confirm the presence of attentional impairment in patients with diverse forms of multiple sclerosis. The exclusive modulation of the P3 latency component suggests that the impairment in these patients, at the beginning of the disease, is localized at a central level of cognitive processing and is product of the demyelinating process.