Analysis of slow dynamics of kinematic structure estimation after physical disorder: Constructive approach toward phantom limb pain

摘要

A recent cutting-edge research line in medical field is phantom limb pain, which is caused by slow dynamics in human kinematic-structure with physical disorder. In this study, we analyze the mechanism of phantom limb pain using a computational model that estimates a body link-structure using a non-parametric Bayes approach. The computational model, which is called Dirichlet process Gaussian mixture model with latent joints (DPGMM-LJ), simultaneously estimates a body map and a body link-structure using only tactile information obtained in its body. To analyze the slow dynamics of phantom limb pain, we performed the experiment to confirm the changes of the body map and the body link-structure estimated by DPGMM-LJ. The experiment was performed in a virtual environment using a simple body model while its body part was lost. As tactile information at a lost body part, we set four experimental conditions: the information becomes zero, the information becomes white noise. The slow dynamics of phantom limb pain is discussed by the experimental result.