Stability of neuronal electrical activity pattern evoked by two inputs stimulation

Rat hippocampal dissociated culture on multi electrodes array dish (MED) is useful as minimalized brain model to investigation of principles of brain information processing. Rat hippocampal neuronal cells were cultured on MED with 64 microelectrodes and they reconstructed a complex network. We analyzed stability of neuronal electrical activity pattern after two distinct electrical stimuli. Distances between averaged spike pattern and spike pattern after electrical stimulation for summarizing the activity pattern to temporal axis direction and trial (sweep) axis direction. The distances of the analysis for summarized to temporal axis direction increased immediately after stimulation and after it, recovered to standard level. Moreover, stabilizing points emerge every 100 ms on both analysis for summarizing the activity pattern to temporal axis direction and trial axis direction. These results suggest that the neural network buttress by electrical stimulation and it be complex by two-point inputs.