The mental chronometry during simulated driving tasks in various conditions of Indonesian subjects

Reaction time or response time which is the time from the onset of a stimulus to the motor action performed as a reaction, has been an important measure in driving performance studies. The mental events occurred while responding to certain stimuli is called mental chronometry in experimental psychology. A subtractive method by subtracting the time required by various task performance experiments has been suggested to be the easiest way to analyse mental chronometry. While ethnic differences in task performance have been widely reported, the mental chronometry study involving Indonesian subjects is very limited. Therefore in this study we describe the process of mental chronometry in simulated driving tasks among Indonesian subjects. We performed two experiments, the first was to measure the reaction time to three visual display indicators in the form of analogue, digital and hybrid design, and the second was to measure the driving performance in brake and lane change task during fatigue and non-fatigue condition. In all of the experiments, the reaction time is the dependent variable measured. The analogue design was found to produce longer reaction time than both digital and hybrid design. In general, both brake and lane change reaction time produced longer reaction time than display indicator reaction time. Fatigue was found to lengthen reaction time during driving. Lane change reaction task as the most complicated task, affected by fatigue greater than brake reaction task. In general, fatigue lengthens reaction time greater in the more complex task. Thus, in order to prevent traffic accident, it is necessary to simplify the complicated tasks by making better system and environment design as well as the application of driving assistance system. Future studies using physical and physiological measurement methods involving larger number of subjects is necessary.