Mental stress assessment - a comparison between HRV based and respiration based techniques

Quantitative mental stress measurement is becoming important due to increasing stress in daily routine. There are many academically used methods based on Heart Rate Variability (HRV) for measurement of stress, yet the sensitivity of these methods is questioned in real life setting. Inhalation and exhalation during breathing is related to the sympathetic (SNS) and parasympathetic nervous system (PNS) balance. Stress being the disturbance of the SNS and PNS, changes the patterns of breathing. In this paper we present a comparative study of stress measurement methods including a novel respiration based method and their dependency on factors such as health condition. Data was collected from a population of 253 subjects using wearable sensors.