Burst High Frequency Stimulation Integrated with On-Off Control for Suppressing 4-AP Induced Seizures

摘要

High frequency stimulation is effective in reducing seizure frequency in both animal experiments and clinical trials. In a previous study, immediate suppression of seizures in hippocampus by stimulation at the lesion focus or the com missural tract was conducted. Although the results showed that high frequency stimulation could suppress seizures, it also induced some side effects, such as the after-discharge and conversion of seizure pattern. These side effects would reduce the usefulness of electrical stimulation. In order to improve the efficiency of high frequency stimulation and avoid the side effects, a novel technique, burst stimulation integrated with on-off control, was proposed and tested in animal experiments. Two recording electrodes were inserted into bilateral septal areas of the hippocampus and a stimulation electrode was put on the ventral commissural tract. After seizures were induced by 4-aminopyridine treatment, burst stimulation integrated with on-off control was applied to suppress seizures in an interval of 5 seconds. The effects of burst duration were evaluated. The cumulative charge and stimulation time and the effort saving were calculated as the indices of control performance. The results showed that burst stimulation could suppress the seizures and a smaller duration of burst stimulation could keep the seizure suppressed with less effort. In conclusion, burst stimulation integrated with on-off control could improve the efficiency of high frequency stimulation. It not only prolonged the duration of suppression but also avoided the side effects of high frequency stimulation. In addition, by decreasing the specified burst duration, the control effort and the cumulative charge for maintaining the neural activity in the normal range were also reduced.