Wearable biosensing devices for mental health, wellness, and stress management.

Data gathering for diagnostic purposes often relies on psychological instruments and validated tests applied individually through in person interviews. Such an approach is limited since it relies on a subjective perception of the individual as well as their abilities to recall information concerning their behaviors, thoughts, and feelings. Thus, the accuracy of the assessment tends to be unreliable and prone to bias, stigma, as well as subjective interpretations. Moreover, psychological instruments (such as questionnaires) are often created and validated for a specific population. However, socio-demographic differences, along with cultural, environmental, and educational aspects, are factors that strongly influence the reliability of tests and their results. On the other hand, wearable technology has a promising potential to address such limitations, being well suited for mental health applications. Wearables are capable of capturing physiological and behavioral measures from human users, reducing subjectivity in this process. Wearable biosensing devices are also particularly useful for capturing users' data longitudinally in a non-invasive and unobtrusive way. Physiological data from wearable sensors includes pulse rate, skin conductance, skin temperature, cortisol levels, and respiration rate. Wearable sensors can also detect behavioral data such as sleep patterns, physical activity, and social interactions. These data points combined have proven to be highly effective in detecting an individual's stress, attention, and mood. Hence, studies in mental health, wellness, and stress have increasingly adopted wearable technologies. This chapter provides a comprehensive review of wearable devices and their widespread application for mental health, wellness, and stress management. We cover various form factors, sensors, data analysis techniques and real-world applications. We conclude with a discussion about the best practices, design considerations and future directions to deploy wearable applications that are ethical and fair for users.