|M.Sc Student||Yael Einav|
|Subject||On the Relationship between Arousal Measures of the|
Sympathetic System and Mental Effort
|Department||Department of Industrial Engineering and Management||Supervisor||Professor Emeritus Gopher Daniel|
We investigated changes in sympathetic nervous system activation, in response to variations in continuous and discrete demands in a simulated flight mission, using a newly developed system recording Peripheral Arterial Tone (PAT).
16 subjects performed a computer-simulated agricultural flight task. They were required to fly over a specific lane of a simulated field (continuous task) and change lanes in response to flags, which appeared at varying intervals (discrete task). The difficulty of the task was manipulated by varying the airplane control (single- vs. dual-axis control), and changing the velocity of flight (80, 120, 160, 200, 240 ft/sec) while the difficulty of the discrete task was manipulated by varying the amount of lateral change signaled by the flag (no change vs. 3 lanes of change).
PAT amplitude values were lower- high load (-10%) in the difficult level of the continuous task (higher velocities) and were further attenuated following the appearance of the flag only when a change in the flight position was required (additional constriction of -10%). In dual-axis control load measurements were higher then in one-axis control. Also, compared to Iani, Gopher and Lavie (2002), we obtained smaller changes in reaction to the continuous task and longer reaction to the discrete task. These results support the existence of a reduced marginal response to added load, as is expected in a psycho-physiological function. The results also support the merit of PAT as an on-line joint measure of continuous and discrete demands of a task.