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The cell membrane poration is one of the main assessed biological effects of nanosecond pulsed electric fields (nsPEF). This structural change of the cell membrane appears soon after the pulse delivery and lasts for a time period long enough to modify the electrical activity of excitable membranes in neurons. Inserting such a phenomenon in a Hodgkin and Huxley neuron model by means of an enhanced time varying conductance resulted in the temporary inhibition of the action potential generation. The inhibition time is a function of the level of poration, the pore resealing time and the background stimulation level of the neuron. Such results suggest that the neuronal activity may be efficiently modulated by the delivery of repeated pulses. This opens the way to the use of nsPEFs as a stimulation technique alternative to the conventional direct electric stimulation for medical applications such as chronic pain treatment.

Protein functions and characteristics can highly differ from physiological conditions in presence of chemical, mechanical or electromagnetic stimuli. In this work we provide a rigorous picture of electric field effects on proteins behavior investigating, at atomistic details, the possible ways in which an external signal can be transduced into biochemical effects. Results from molecular dynamics (MD) simulations of a single superoxidismutase (SOD) enzyme in presence of high exogenous alternate electric fields will be discussed.

Deep Brain Stimulation (DBS) is a clinically suitable technique for the treatment of the Parkinson's disease. Recently, also other neurological disorders such as Tourette syndrome, obsessive-compulsive disorder, epilepsy are being to be treated with DBS. However, the debate on its therapeutic mechanisms of action is still open. In order to a better understanding of such mechanisms, in this work the attention is focused on the DBS micro-stimulation. Indeed, a micro electrodes registration and stimulation is a fundamental step, during the surgical phase, to optimize the technique in terms of DBS lead positioning and DBS signal parameters. In this paper a dosimetric analysis with micro electrodes has been carried out, showing a more focused distribution of the electrical potential induced in the neuroanatomical tissues and changes of the excited/inhibited regions, respect to a macro electrodes stimulation.

A number of experimental investigations have evidenced the extraordinary sensitivity of neuronal cells to weak input stimulations, including electromagnetic (EM) fields. Moreover, it has been shown that biological noise, due to random channels gating, acts as a tuning factor in neuronal processing, according to the stochastic resonant (SR) paradigm. In this work the attention is focused on noise arising from the stochastic gating of ionic channels in a model of Ranvier node of acoustic fibers. The small number of channels gives rise to a high noise level, which is able to cause a spike train generation even in the absence of stimulations. A SR behavior has been observed in the model for the detection of sinusoidal signals at frequencies typical of the speech.

Endogenous noise has been shown to play a central role in the detection of an electromagnetic signal in the nervous system. In this work, following a biomedical perspective, an exogenous noise applied to a realistic feedforward network model has been considered. It will be shown that, if the exogenous noise is properly filtered and its level is adjusted, a clear optimization of network encoding of an electromagnetic signal, representative of an external stimulation, is obtained through the stochastic resonance paradigm.

Deep Brain Stimulation (DBS) has revealed a convincing clinical efficacy in Parkinson's diseases and essential tremor. Unfortunately, to date no clear understanding of the therapeutic mechanisms has been achieved. Characterization of the distribution of the electrical quantities inside the target areas of the central nervous system is one fundamental step ahead. Starting from the studies that so far addressed this issue, aim of this work is to quantify the role of some parameters, such as dimensions of the conducting domain and of boundary conditions, on the distribution of the fundamental electric quantities inside the brain target area.