Measuring emotions in traffic

This paper contains the text of a presentation held at the European Science Foundation Congress ‘Towards Safer Road Traffic in Southern Europe' (May 31st – June 2nd, 2001, Ankara , Turkey). In this paper, methods to measure emotions are reviewed and possible applications for traffic research are discussed. Several studies show that emotions have effects on all kinds of cognitive processing. Therefore it is likely that a number of driving tasks is affected by emotions as well. As yet, not much is known about the way in which driving behaviour is affected by emotions and what the consequences for traffic safety are. When doing research on this topic, one should first be able to recognise and measure an emotion. Therefore this paper presents three categories of methods to measure emotions. The first category is observing overt behaviour. Overt behaviour aims to measure actions or action tendencies, for example by listening to vocal patterns, looking at facial expressions, or watching bodily gestures. An investigation into horn honking behaviour is an example of the use of this method in traffic. The second category is formed by physiological measures, for example heart rate and skin conductance. In traffic, this measure can be used, for example by measuring heart rate while driving. The third category is self-reported behaviour, for example interviews, diaries or questionnaires. This measure can be used while driving, for example by asking subjects how they feel at a particular moment. It can also be used after driving, for example by asking subjects to fill in a questionnaire about the emotions felt while driving. Of each category of measures, examples are given of past use of these measures in traffic research. Also, implications for further research are discussed.