(1) Background: Ultrasound has been used for noninvasive stimulation and is a promising technique for treating neurological diseases. Epilepsy is a common neurological disorder, that is attributed to uncontrollable abnormal neuronal hyperexcitability. Abnormal synchronized activities can be observed across multiple brain regions during a seizure. (2) Methods: we used low-intensity focused ultrasound (LIFU) to sonicate the brains of epileptic rats, analyzed the EEG functional brain network to explore the effect of LIFU on the epileptic brain network, and continued to explore the mechanism of ultrasound neuromodulation. LIFU was used in the hippocampus of epileptic rats in which a seizure was induced by kainic acid. (3) Results: By comparing the brain network characteristics before and after sonication, we found that LIFU significantly impacted the functional brain network, especially in the low-frequency band. The brain network connection strength across multiple brain regions significantly decreased after sonication compared to the connection strength in the control group. The brain network indicators (the path length, clustering coefficient, small-worldness, local efficiency and global efficiency) all changed significantly in the low-frequency. (4) Conclusions: These results revealed that LIFU could reduce the network connections of epilepsy circuits and change the structure of the brain network at the whole-brain level.

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Neural interface is man-made information pathway through which biological nerve system could communicate directly with electromechanical devices including computer, robot and even cyborg. This paper introduces a novel neural interfacing electrode array capable of bidirectional information transmission and multi-signals recording. The novel flexible electrode array with 32 channels enables close-looped control and feedback neural interfacing researches with the capability of both electrical stimulation and simultaneous recording of electroencephalogram (EEG), electromyogram (EMG), electroneurogram (ENG) signals. The electrochemical impedance spectroscopy (EIS) measurement of the electrode array was carried out to evaluate the electrode array electrochemical performance in the electrophysiology frequency range. Electrical stimulation to peripheral nerve was performed with various stimulation configuration of ENG electrode site pairs to produce distinct activation patterns. Muscle action potentials of the gastrocnemius of the hind limb indicated different configuration of electrode site pairs could generate distinct stimulating effect. In addition, three groups of in vivo experiments were conducted to demonstrate the recording ability of the electrode array for nerve signals. The data from 32 channels verified the effectiveness of this flexible electrode array in simultaneous recording of EEG/EMG/ENG in vivo.