Estimation of subjective stress via finger plethysmogram

It could be very important and useful to enable human stress to be estimated on basis of quantitative values via objective analysis. There have been several approaches to estimate the stress so far. Most of them need a lot of time to measure or calculate it, and what is more, they might cause physical or mental burden for human subjects. The purpose of our study is to propose and develop a method to estimate subjective stress through a simple approach which doesn't cause much burden for users. In this paper we propose a method, which is called TPAf (Turning Point Amplitude via finger plethysmogram). Original TPA is a kind of heart rate variability analysis and needs to attach sensors on his/her breast. Our experimental results indicated that it has a certain relationship between subjective stress and TPAf. A method based on TPAf could be efficient to estimate subjective stress.