Modulation of dorsolateral prefrontal cortex (DLPFC) through repetitive transcranial magnetic stimulation (rTMS) during capsaicin induced pain: effects on nociceptive control and motor cortical circuits

Sequenziamento temporale ed elaborazione neurale: una prospettiva psicofisiologica

TWO CASES OF NON-ALCOHOLIC WERNICKE ENCEPHALOPATHY SUCCESSFULLY TREATED BY THIAMINE REPLACEMENT: DIAGNOSTIC AND THERAPEUTIC CONSIDERATIONS

Wernicke’s encephalopathy (WE) is an acute neurologi- cal disorder, due to a lack of thiamin (vitamin B1) which is observed mainly in alcoholic patients. Unfortunately, the syn- drome is underestimated in clinical practice and most often recognized only on autopsy, especially among non-alcoholics. The common clinical picture include mental status changes, ocular dysfunction, and gait ataxia. Treatment consists of timely thiamine replacement through intravenous infusion. We describe the case of two patients who developed a non-alcoholic WE post-surgical, regressed completely after intravenous infusion of thiamine. These cases suggest intere- sting diagnostic and therapeutic implications.

Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) during capsaicin-induced pain: modulatory effects on motor cortex excitability

Evidence by functional imaging studies suggests the role of left DLPFC in the inhibitory control of nociceptive transmission system. Pain exerts an inhibitory modulation on motor cortex, reducing MEP amplitude, while the effect of pain on motor intracortical excitability has not been studied so far. In the present study, we explored in healthy subjects the effect of capsaicin-induced pain and the modulatory influences of left DLPFC stimulation on motor corticospinal and intracortical excitability. Capsaicin was applied on the dorsal surface of the right hand, and measures of motor corticospinal excitability (test-MEP) and short intracortical inhibition (SICI) and facilitation (ICF) were obt…

Modulation of pain perception by transcranial magnetic stimulation of left prefrontal cortex.

Evidence by functional imaging studies suggests the role of left dorsolateral prefrontal cortex (DLPFC) in the inhibitory control of nociceptive transmission system. Repetitive transcranial magnetic stimulation (rTMS) is able to modulate pain response to capsaicin. In the present study, we evaluated the effect of DLPFC activation (through rTMS) on nociceptive control in a model of capsaicin-induced pain. The study was performed on healthy subjects that underwent capsaicin application on right or left hand. Subjects judged the pain induced by capsaicin through a 0–100 VAS scale before and after 5 Hz rTMS over left and right DLPFC at 10 or 20 min after capsaicin application in two separate gr…

Effects of cerebellar TMS on motor cortex of patient with focal dystonia: a preliminary report

Recent evidence suggests a role for cerebellum in pathophysiology of dystonia. Here we explored, the cerebellar modulation of motor cortex in patients with focal upper limb dystonia. Eight patients and eight controls underwent a transcranial magnetic stimulation protocol to study the cerebellar-brain-inhibition (CBI): a conditioning cerebellar stimulus (CCS) was followed 5 ms after by the contralateral motor cortex stimulation (test stimulus: TS). We explored the effects of CBI on MEP amplitude, short intracortical inhibition (SICI) and intracortical facilitation (ICF) measures. At baseline no differences in TS-MEP amplitude, SICI or ICF were found between patients and controls. Cerebellar-…