Analysis of Brain Activity during Local Hot-Cold Stimulus Using Near-Infrared Spectroscopy (Analysis of Brain Activity during Hot Stimulation)

Methods such as the Predicted Mean Vote and Standard New Effective Temperature were developed to evaluate thermal comfort. However, radiation and convection of heat due to factors such as sunlight or air cycle are stronger in automobiles than in indoor environments. Moreover, the thermal environment in automobiles is non-uniform and locally inhomogeneous, which makes evaluating thermal comfort in automobiles difficult. We aim to evaluate the local thermal environment by analyzing brain activity. The final goal is to develop an air conditioning control system in automobiles using a brain machine interface. Herein, we describe analysis of brain activity during local hot stimulation. We measured oxyhemoglobin (oxyHb) levels in the prefrontal cortex and the primary somatosensory cortex while subjects touched aluminum plates that were heated or cooled to different temperatures. The results show that oxyHb changes in the prefrontal cortex vary according to the temperature of the aluminum plates.