The Electrode Registration System Based on the Scale ICP

The registration of EEG electrodes with a head model is the initial step for advanced EEG data analysis such as inverse problem solution and various high-resolution mapping. This paper presents a real-time system for registering the point set of EEG electrodes to head model reconstructed from an anatomic MRI. In this system, a friendly interface is designed for user to select the desired reference points using mouse click conveniently, and these selected reference points are adopted for the Iterative Closest Points (ICP) based registration routine. Considering the possible bias introduced by the mismatch scale between two point-sets, we used an improved ICP algorithm, i.e., Scaling Iterative Closest Point (SICP), to perform the registration. The comparison between the original ICP and SICP demonstrates that SICP could robustly register the electrode points to the head model even if the two points are of large scale difference.