Stress and EEG

Abstract

Many people suffer from stress in their everyday life. While there is a close relationship between stress and mental health, psychological stress (and associated emotions such as anger, anxiety, and depression), can also have effects on physical health. Indeed, chronic psychological stress can change the responsiveness of central-peripheral regulatory systems (Fuchs & Fluegee 1995; Fuchs, Uno, & Fluegge 1995), potentially rendering them less efficient or adaptive in terms of supporting health. Conditions such as chronic stress, depression, and anxiety have been found to be associated with abnormal autonomic nervous system (ANS) functioning (Cohen et al., 2000; Hughes & Stoney 2000). Accordingly, stress is one of the major factors contributing to chronic disorders (Decker et al., 1996; Lawrence & Kim 2000). Stress also influences the desire to work, performance at work, and one’s general attitude toward life (NIOSH, 1999). Within the industry sector, higher stress levels and stress-related disease lead to decrease in company performance and increase in medical expenses (Cooper, 1996; Manning, et al., 1996). In 2008 in Korea, there were 1,967 deaths associated with occupational cases. Almost half of these deaths (974, or 49.5%) could be ascribed to heart or brain blood vessel disease (Ministry of Labor, 2008). This is not surprising given that stress is implicated in 75% of all heart and brain blood vessel diseases (Belkic, et al., 2004). It is thus apparent that stress can increase social and economic losses and decrease a country’s competitiveness (Driskell & Salas, 1996). Therefore, precautionary measures to reduce stress and adequate management of this condition are essential for both individual health and the welfare of society at a broader level. This chapter reports on relationships among psychological stress, the EEG (Electroencephalogram), ECG, and salivary cortisol in people suffering from chronic stress. We hypothesized that chronic stress will have negative effects on the central-ANS and physiological responsiveness. There are many bio-signal channels by which stress can be potentially quantified, including ECG, EEG, and the skin conductance response (SCR) (Kohlish & Schaefer 1996; Gevins et al., 1998). Even so, determining the stress level of any given individual can be difficult. Related to this is debate concerning the extent to which the EEG can be used to reliably measure stress. However, this chapter presents data showing that there are significant correlations between EEG measures and other indices of stress, including the ECG and salivary cortisol. Also, it revealed relationships between high beta Source: Convergence and Hybrid Information Technologies, Book edited by: Marius Crisan, ISBN 978-953-307-068-1, pp. 426, March 2010, INTECH, Croatia, downloaded from SCIYO.COM