The Italian technical/administrative recommendations for telemedicine in clinical neurophysiology.

Recent advances in technology, information technology, Internet networks, and, more recently, fiber optics in industrialized countries allow the exchange of a huge amount of data, in real time, across the globe. The acquisition of increasingly sophisticated technologies has made it possible to develop telemedicine, by which the specialist's evaluation can be carried out on the patient even remotely. In Italy, this very useful tool, although possible from a technological and information technology point of view, has not been developed because of the lack of clear and univocal rules and of major administrative obstacles related to the Italian Public Health System. To promote telemedicine implementation in Italy, the Italian Society of Clinical Neurophysiology and the Italian Society of Telemedicine together with the National Centre for Telemedicine and New Assistive Technologies of the Italian Higher Institute of Health prepared these inter-society recommendations. Because of potential forensic value of these recommendations, they were prepared considering the current regulations and the General Data Protection Regulation and will provide the basis for a Consensus Conference planned to discuss and prepare National Telemedicine Guidelines.

Transcallosal inhibition dampens neural responses to high contrast stimuli in human visual cortex.

Visual cortical areas in the two hemispheres interact via the corpus callosum, but the precise role of the callosal pathway in visual processing remains controversial. Here we have investigated the function of transcallosal projections in human primary visual cortex (V1). Visual evoked potentials (VEPs) triggered by grating stimuli of different contrasts were recorded before and after functional inactivation of the occipital cortex of one hemisphere via off-line low-frequency repetitive transcranial magnetic stimulation (rTMS; 0.5 Hz stimulation for 20 min). VEPs were recorded in V1 before (T0), immediately after (T1) and 45' following the completion of rTMS (T2). We found that low-frequency rTMS had an inhibitory effect on VEPs amplitudes at all contrasts in the treated side. Remarkably, reduction of VEP amplitudes in the inhibited hemisphere at T1 was accompanied by an increase in VEP amplitudes in the contralateral side only at mid-high contrasts (50-90%). This disinhibitory effect was observed with both central and hemifield stimulation. No changes in VEP amplitudes were observed when rTMS was applied to a cortical site more anterior with respect to V1. These data provide the first evidence that a mechanism of transcallosal inhibition dampens neural responses at high contrasts in human visual cortex.