Spatiotemporal electrical activity patterns in snail brain neuronal networks

Spatiotemporal electrical activity patterns were investigated in the ring ganglion of the pond snail Lymnae stagnalis using a needle type electrode array. Spontaneous electrical activity was observed simultaneously from several neurons in normal solution. Some neurons with the electrical activity of a period of 20 sec which is similar period of Lymnae respiratory rhythm were observed. The electrical activity patterns drastically changed in high potassium ion solution. The huge amplitude periodic and synchronized electrical activity with a period of 5 sec was observed from several electrodes. These results suggest that the high potassium ion solution collapse the respiratory rhythms and introduce a new rhythm which a large population of neurons participate.