Influence of modafinil on somatosensory input processing in the human brain-stem.
OBJECTIVE
Since high frequency oscillations (HFOs) evoked by upper limb stimulation are susceptible to arousal fluctuation, we verified whether administration of modafinil, a vigilance promoting drug, modifies such responses at different levels of the somatosensory system.


METHODS
HFOs were obtained in 6 healthy volunteers by 500-700 Hz filtering of right median nerve somatosensory evoked potentials, before and 2 hours after the administration of 100 mg modafinil. Raw data were further submitted to brain electrical source analysis.


RESULTS
Modafinil significantly increased subcortical HFOs, as well as the strength of a dipolar source at the base of the skull.


CONCLUSIONS
Our data suggest that modafinil exerts its action also at the level of the brain-stem, where it interferes with the processing of somatosensory ascending inputs.
Department of Neurosciences, Cathodic University, L. go A. Gemelli 8, 00168 Rome, Italy. dellamarca@rm.unicatt.it
Giacomo
G
Della Marca
Domenico
D
Restuccia
Marco
M
Rubino
Toni
T
Maiese
Pietro
P
Tonali
D000328:Adult; D001559:Benzhydryl Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D001933:Brain Stem / Q000187:drug effects* / Q000502:physiology*; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000009:adverse effects; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects*; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000502:physiology; D000077408:Modafinil
D001559:Benzhydryl Compounds; D000697:Central Nervous System Stimulants; D000077408:Modafinil