This chapter reviews and evaluates major studies, reported in the existing literature, that have used psychophysiological techniques in the vehicle environment. It emphasises research conducted within vehicles during real-load or closed-circuit studies. Electrodermal (EDR) measures include all psychophysiological variables (PPV) that describe changes in the skin's electrical conductance. As arousal increases, skin resistance decreases. As for other PPV discussed here, EDR studies of driving behaviour may be classified into: (1) 'stimulus/situational variable studies, where differential psychophysiological activity is examined as a function (usually a correlation) of different types of stimuli in the traffic environment; (2) the use of psychophysiological techniques to discriminate between different subject groups or 'subject variables'. Other PPV techniques include: (1) electrocardiogram (ECG) measures of the heart's electrical activity; (2) electromyography (EMG) techniques to measure the electrical activities of specific groups of muscles; (3) electrooculography (EOG) measurements of eye movements; (4) electroencephalography (EEG) records of the brain's electrical activity. PPV techniques are continually evolving, as new PPVs, monitoring apparatus and analysis techniques are developed and tested in the search for a reliable physiological index of mental workload. But much further research will be needed before they become really useful.
Samenvatting