Characteristic Extraction of Mental Disease Patients by Nonlinear Analysis of Plethysmograms

Abstract

We measured the pulse waves of 196 mentally ill patients and 113 healthy students. Using heartbeat changes, we calculated the values of their sympathetic nerves, parasympathetic nerves, and autonomic nerve balance. In addition, we calculated the largest Lyapunov exponents (LLE) by non-linear analysis of plethysmograms. Values were analyzed by group. The results revealed a significant relationship between LLE and the autonomic nerve balance. The sympathetic nerve values in the patient group were significantly higher than those in the student group, whereas the LLE values were significantly lower. Furthermore, we illustrated the dynamic change in the results for single participants over several testing times. The measurement of pulse waves is easy and economical and does not put a strain on the subject. Additionally, these values can provide information that is more accurate than medical examination obtained from an interview. Our study contributed to the existing methodology in this field, and future data collection and measurement will be carried out. We hope that our study will be useful for neurologists and psychotherapists in their detection and treatment of mental illness.

Toward the development of a cost-effective e-depression detection system

“…Nonlinear dynamical analysis methods described in the foregoing sections were applied to extract the bio-signal features of the mental and control subjects. The experimental data used in this study is the same data recently studied in [23]. The dataset consists of 195 patients diagnosed with depression and 113 students considered as the control subjects.…”

“…In our previous study [23], the LLE and autonomic n erve balance (ANE) values, which were implemented in the commercial software Lyspect, were used for the detection of depression using the finger pulse waves. The concept of autonomic nerve balance [27] stems from the fact that the human nervous system has two major parts: the voluntary and the autonomic systems.…”

Indication of Mental Health from Fingertip Pulse Waves and Its Application

“…In order to investigate the possibility of identifying physiological patterns characteristic of mental illness sufferers, we conducted measurement from subjects of mentally ill patients and healthy people [29, 30]. The former group was composed of 43 people, selected from a total of 195 patients each of whom was diagnosed with a certain mental illness.…”

Smartphone-based Device for Checking Mental Status in Real Time

“…For the results of our recent studies, specifically, the method of measuring and analysing fingertip pulse waves have been applied to various research subjects concerning detection of mental changes (Oyama-Higa et al, 2008;Wang et al, 2012) and check-up for mental and cognitive disorders, such as dementia (Oyama- Higa and Miao, 2006;Oyama-Higa et al, 2008;Pham et al, 2015) and depression (Oyama-Higa et al, 2008;Hu et al, 2011;Pham et al, 2013).…”