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Background: Non-invasive magnetic stimulation therapies have become a widespread neuromodulation method utilized in the treatment of mood disorders. Although these methods have shown efficacy in the treatment of psychiatric disorders such as bipolar affective disorder and depression, a few studies have been done on Parkinson's disease (PD). Objective: This study was executed to demonstrate the effectiveness of focused transcranial magnetic stimulation (fTMS) for the treatment of PD. For this aim, a new stimulation coil design with the semi-hexagonal core was used to concentrate magnetic flux in the particular innervation nucleus. Several TMS protocols were tested to stimulate the STN region of 6-OHDA lesioned rats to determine the most effective treatment. Results: The progress of treatment was investigated by recording and analyzing the neurophysiological activity of the primary motor cortex and locomotor behaviors. After 6-OHDA injection, sharp increases in the energy and power spectral density of beta and low- gamma band were caused. Also, the motor activities of rats reduced, and the degree of catalepsy increased significantly. By completing the proposed 1Hz r-TMS treatment, the amount of energy and power density in these bands diminished and came close to the baseline. Furthermore, debilitating motor fluctuations were reverted considerably. Conclusion: Experimental results reveal that after 40 days of the non-invasive procedure, both oscillatory activity and the locomotor behavior produce remarkable changes. The 1Hz r-TMS showed acceptable performance in a reduction of symptoms in the PD. The outcomes of the animal trials have raised some hopes to employ the findings of this study in human clinical research.

Background: Growing wireless communication market is forcing the engineers to design portable and cheaper devices. This could be completed by reducing power consumption and saving battery life. Objective: In this study, a bandpass filter with a central frequency of 80 MHz with the ability to digitally tune the central frequency was designed and simulated. OTA-C blocks (gm-C) were utilized to implement the filter. For this purpose, instead of using a fixed capacitor, we use an array of voltage-variable capacitors that are placed in the form of a capacitor bank. Results: The proposed filter was implemented at the transistor level with 180 nm CMOS technology and simulated with the RF H-spice software. In the proposed filter, the bandwidth of 20 MHz was digitally tuned by 1 MHz increments. The average power consumption at the center frequency of 80 MHz was equal to 24.23 mW. Conclusion: The practical analysis of the digitally tuning filter technique and the simulation results are explained. A comparison of the performance parameters of the simulated filter with state-of-the-art filters indicates that the proposed filter can change its bandwidth over a wide range with the lower power consumption and the lower noise.

This research is executed to measure the transcranial magnetic stimulation (TMS) systems resolution. For the first time in this study, voxel resolution is proposed and exploited to evaluate TMS systems accuracy. To reach this goal novel procedure in four steps is presented. First, a small recording electrode is implanted in the targeted point of the brain, and then stimulation session is started. Induced potential in micro coil is measured and digitalized. Then the transcranial stimulation coil and test object are moved by micromanipulator and next measuring stage starts. The manipulator will sweep the 512 μl by step of 400 µm in 3-D spaces. Ultimately the measured resolution for particular stimulation coil/core is calculated. The prototype of suggested process is fabricated and tasted by in vitro and in vivo experiments. The experimental outcomes and finite element analysis results proved that the offered procedure is a powerful investigational device to measure TMS systems resolution.