[The study on local field potentials in rat's primary motor cortex during pressing paddle behavior].

Objective: The local field potential (LFP) is a summation of dendritic potentials. The main objective of the present work is to view the features of LFP in M1 during the experimental rat pushed a paddle with the right forelimb.

Methods: Four rats were trained to press a paddle with the right forelimb for water. Then Two bundle micro-electrode with four channels were implanted into the rat's left and right primary motor cortex (M1)(AP + 3.0 mm, ML +/- 1.6 mm, H-1.6 mm) with stereotaxic apparatus. After three days recovery, 8-channel Deep-EEG and the pulse signal of paddle pressed were recorded during the rats were in operant chamber, and at the same time, the behavior were also recorded with video recorder.

Results: The LFP in left M1 were defined as the substance between two channel deep-EEG. It is found that low frequency, high amplitude signal appear aligned with the paddle pressed pulse signals. With threshold detect method, about 80% press-paddle behavior could be detected.

Conclusion: The result indicates that LFPs in this position in M1 are relative to forelimb's movement, and a powerful brain-computer interface system maybe developed with the LFPs.