An Interactive Physio-psychological Model on Understanding Stress among Individuals Performing Sedentary Computer Tasks

The overall purpose of this thesis was to investigate the acute physiological and psychosocial responses exposed to stress-induced workloads among computer users with and without neck pain.;The pilot study examined the effects of physical and mental workload in three computer tasks on muscle activity and cardiovascular measures. 14 healthy, pain-free adults were asked to complete three tasks of 15 minutes each. The tasks were copy-typing, typing at progressively faster speeds, and mental arithmetic plus fast typing. Median muscle activity was examined in 5-minute intervals during each task and each rest period, and statistically significant differences in the time factor and time x task factors were found in the bilateral cervical erector spinae and upper trapezius muscles. Heart rate (HR) and blood pressure (BP) showed significant differences during tasks compared to baseline. The aims of the main study were to investigate the responses of the objective measures in the muscular system, neurophysiological system, and cardiovascular system. 46 adult university students were categorized into the Pain-Free Group (n = 23) or the Neck Pain Group (n = 23). Each participant was required to perform five tasks: a self-paced copy-typing task, a fast copy-typing task, a fast copy-typing Stroop color test (CWT), a verbal CWT, and a prolonged CWT using a standardized computer workstation. The overall results indicated that the combined high-physical and high-mental workloads elicited consistent trends of greater increases in activity of various physiological measures compared to high-physical or high-mental workloads alone. Brain activity seemed to be more sensitive in response to all three types of workload variation, whereas muscular activity seemed to be more responsive to physical workload or physical-plus-mental workload. HRV showed more variable response patterns in the Neck Pain Group. The Neck Pain Group experienced significant increases in feelings of discomfort and anxiety; in contrast they also accompanied by poorer behavioral performance.;In conclusion, the study confirms the important association between physiological and psychosocial responses in people with and without neck pain. The results also support the phenomenon that individuals with chronic pain have pain-related cognitive impairment and maladaptive physiological responses.