As many industrial workers are involved with mental work, for example, monitoring, inspection, or computer data entry etc., concerns for mental load evaluation are increased.
This study provides that eyeblink can be used as a method of mental load evaluation. Four subjects without color blindness are asked to perform the monitoring task of binary choice type under five levels of mental load(signal rate). In each task, eyeblink rate and eyeblink interval time were measured from the subjects. The results indicate that eyeblink rate does decrease with an increase in mental load. In addition it was found that both eyeblink interval time and eyeblink interval time variation increased for an increase in mental load. It is concluded that change of eyeblink rate, eyeblink interval time and eyeblink interval time variation are regarded as generalized response to the imposition of a load.
