ECG-Based Concentration Recognition With Multi-Task Regression.

Abstract

Recognition of human activities and mental states using wearable sensors and smartphones has attracted considerable attention recently. In particular, prediction of the stress level of a subject using an electrocardiogram sensor has been studied extensively. In this paper, we attempt to predict the degree of concentration by using heart-rate features. However, due to strong diversity in individuals and high sampling costs, building an accurate prediction model is still highly challenging. To overcome these difficulties, we propose to use a multitask learning (MTL) technique for effectively sharing information among similar individuals. Through experiments with 18 healthy subjects performing daily office works, such as writing reports, we demonstrate that the proposed method significantly improves the accuracy of concentration prediction in small sample situations. The performance of the MTL method is shown to be stable across different subjects, which is an important advantage over conventional models. This improvement has significant impact in real-world concentration recognition because the data collection burden of each user can be drastically mitigated.