Indoor odor exposure effects on psycho-physiological states during intellectual tasks and rest

The responses of five human subjects to two indoor airborne odors (mint and cypress) were examined to determine the effect of perceived air quality and odor type and duration on several psycho-physiological variables during periods of rest and while performing intellectual tasks. An olfactometer system was installed in a climate chamber at the University of Tokyo, with the nozzle located on a desk just to the right of the task-performance screen. The odor concentration presented to the subject was adjusted to keep the perceived odor intensity constant at level 2 (weak) as established in a pretest. Subjects performed a simulated office task, 12 min of Sudoku (number placing puzzle), or rested for 7 min. The task and the rest periods were repeated six times each (except for first and last rests) during one day's exposure. Odor exposures during tasks and rest involved one of the two odors for either a short or long period. During the 3 min between a task and rest, subjects rated their perceptions of odor int...