Motor imagery (MI) brain–computer interface (BCI) and neurofeedback (NF) with electroencephalogram (EEG) signals are commonly used for motor function improvement in healthy subjects and to restore neurological functions in stroke patients. Generally, in order to decrease noisy and redundant information in unrelated EEG channels, channel selection methods are used which provide feasible BCI and NF implementations with better performances. Our assumption is that there are causal interactions between the channels of EEG signal in MI tasks that are repeated in different trials of a BCI and NF experiment. Therefore, a novel method for EEG channel selection is proposed which is based on Granger causality (GC) analysis. Additionally, the machine

Finding differences between the brain signals of professional visual artists and non-artists during mental imagery of four paintings brought up the idea of using neurofeedback to resemble the patterns of the brain activity of non-artists to those of professional visual artists. To this end, the protocol for increasing the beta band activity and inhibiting the alpha band activity in channel T5, was utilized to train 12 non-artist subjects (7 subjects in the experimental group and 5 subjects in the sham group). To train the brain activity of the subjects, the fuzzy adaptive neurofeedback training procedure was used in which a variable scoring index and a mental fatigue index were defined to determine the success rate of the subjects and to

Electrochemotherapy (ECT), the combination of electric pulses (EPs) and an anticancer drug, is a type of cancer treatment method. We investigated the effect of 217-Hz magnetic fields (MFs) similar to that generated by GSM900 mobile phones, as intervening factors, on proposed mechanisms of ECT including permeability, tumor hypoxia and immune system response. The 4T1 cells were exposed to extremely low-frequency (ELF)-MFs at 93, 120 or 159 ?T intensities, generated by Helmholtz coils 10?min, and then put in individual groups, comprising no treatment, chemotherapy, EPs or ECT. The cell viability was evaluated. Then, two treatment protocols were selected for in vivo experiments. The mice with 4T1 tumor cells were exposed to ELF-MFs 10?min/day u

Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation technique that is affordable and easy to operate compared to other neuromodulation techniques. Despite this method is promising in treating neurological diseases and enhancing cognitive functions, the precise mechanism of the effect of this sub-threshold stimulation has not been understanded well. Understanding the mechanism is important in designing the proper protocol and system for the brain's electrical stimulation. The aim of this paper is to identify this mechanism with the neural modeling approach. As the results of some physiological studies have shown that under tDCS, sudden calcium signaling associated with calcium signaling of astrocyte cells in th

Electrochemotherapy (ECT) is a new and promising treatment strategy for cancer treatment. The aim of this work is to investigate the effect of 900?MHz radiofrequency electromagnetic fields (RF-EMFs) on the mechanisms of ECT (low voltage, high frequency) including cell permeability in vitro, and tumor hypoxia, immune system response in vivo, and on volume of tumors treated with ECT (70?V/cm, 5?kHz). The 4T1 cells were exposed to RF-EMFs at 17, 162, or 349??W/cm2 power densities, using GSM900 simulator, 10?min. The cells were then put in individual groups, comprising of no treatment, chemotherapy, electric pulses (EPs), or ECT. The cell viability was evaluated. The mice with 4T1 tumor cells were exposed to RF field 10?min/day unt

Background: Over the last decades, there has been an increasing trend in using cell phones which are exposing us to Radio-Frequency (RF) and Extremely Low Frequency (ELF) magnetic field with various known and unknown biological effects. This protective study aimed to investigate the impact of environmental 217 Hz (as an ELF) magnetic fields generated by mobile phones on angiogenesis as an essential factor in tumor growth, in vitro and in vivo. Material and Methods: Magnetic fields with amplitudes of 0.5, 6, 22, 44, 65 & 159 ?T were exposed on Human umbilical vein endothelial cells (HUVECs) and proliferation and viability of cells were measured. 3D angiogenesis assay was done by culturing HUVEC-covered microbeads in collagen gel and counting

Background: In the present study, we investigated the application of pulsed magnetic field (MF) (3.5 T, 1 Hz, 8 square-wave/160 ?s) permeabilization on murine breast adenocarcinoma cells when administering bleomycin (BLM) in vivo. Objective: This cross-over study aims to find a noninvasive method to facilitate penetration of hydrophilic anti-cancer drugs through the cancerous cells membrane into the cytosoll in order to minimize the side effects of the chemotherapy treatments of tumors.Material and Methods: In this cross-over study, a total of 50 female Balb/c mice were tumorized via homograft. After about 2 weeks, magnetic pulses (3.5 T, 1 Hz, 8 square-wave/160 ?s) were applied to tumor-bearing mice 3 min after intratumoral BLM solution in

High selectivity and low impedance are preferred properties for neural microelectrodes. The localized and controlled release of drugs from the nanostructured coatings may reduce brain tissue responses for chronic recordings. Here, polypyrrole (PPy) nanotube was chemically synthesized inside an alumina template. The formation of nanotube was confirmed by scanning electron microscopy (SEM) of the cross-section of templates. Then, PPy nanotube was loaded with dexamethasone (Dex) as a dopant during the polymerization process up to 93%. Successful loading of Dex molecules into the PPy nanotube was verified by the Fourier-transform infrared spectroscopy (FTIR). Gold nanoparticles were synthesized via the reduction of Au3+ ions on the

Differences in brain signals between skilled and non-skilled individuals led to the idea of using neurofeedback (NFB) in order to imitate brain activity patterns in skilled individuals, reinforce performance of novice people, and ultimately help them in terms of achieving skills in a faster manner. This study shed light on visual skills and aimed at designing a NFB training protocol specifically enhancing the performance of novice visual artists. For this purpose, a set of features (energy, mean and standard deviation of wavelet and cepstral coefficients, wavelength, the first zero crossing of autocorrelation function, correlation and fractal dimensions, approximate and sample entropy and scaling exponent) of EEG signals recorded from two g

Irreversible electroporation (IRE) is a process in which the cell membrane is damaged and leads to cell death. IRE has been used as a minimally invasive ablation tool. This process is affected by some factors. The most important factor is the electric field distribution inside the tissue. The electric field distribution depends on the electric pulse parameters and tissue properties, such as the electrical conductivity of tissue. The present study focuses on evaluating the tissue conductivity change due to high-frequency and low-voltage (HFLV) as well as low-frequency and high-voltage (LFHV) pulses during irreversible electroporation. We were used finite element analysis software, COMSOL Multiphysics 5.0, to calculate the conductivity change

Background: Increasing technological advances in the field of biological signal recording, along with diverse available data storage and sharing facilities, has made it much easier for researchers to access extensive biological data for use in their studies. Today, data once recorded in a study can be repeatedly reused by other researchers through access to shared databases. Access to biosignal pools, on the one hand, can save considerable energy and reduce costs by preventing duplicate studies. On the other hand, it improves opportunities for meta-analysis and in-depth studies using diverse datasets with greater statistical power, which provides more reliable results, as well as new insights into biological issues. However, the lack of som

Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation technique that is affordable and easy to operate compared to other neuromodulation techniques. Despite this method is promising in treating neurological diseases and enhancing cognitive functions, the precise mechanism of the effect of this sub-threshold stimulation has not been understanded well. Understanding the mechanism is important in designing the proper protocol and system for the brain's electrical stimulation. The aim of this paper is to identify this mechanism with the neural modeling approach. As the results of some physiological studies have shown that under tDCS, sudden calcium signaling associated with calcium signaling of astrocyte cells in th