[Noise, sleep and behavior]

The negative effects of noise on sleep and behaviour have been related to three mechanisms: a physiological arousal (above a certain threshold of noise), an aversive reaction and an interference with non auditive neurophysiological and mental processes. The perturbation of verbal communication and the effects of sleep are the directly observable consequences. The negative effects of noise above a certain threshold on sleep have been demonstrated both in experimental conditions and in real life. They concern length, EEG pattern, and subjective quality and produce an increase of irritability and tiredness. There is no habituation. In all populations studied, strong discomfort is expressed by 50% of the subjects living in an area with an Ldn of 75 dB in the case of air traffic noise, the same results being obtained with ground traffic for a 5-15 dB higher level. Objective expressions of discomfort: use of aural protections, closing the windows, staying indoor, changing residence, increase linearly with the intensity of noise. Noise influences the incidence of stress-related disorders: hypertension, related cardio-vascular diseases, psychosomatic and psychological disorders. It has been shown by the use of different techniques (epidemiological studies based on the frequency of medical contacts, on the diagnoses made by general practitioners, on the use of specific drugs, and on the examination of the whole population) that the prevalence increases in relation with the level of noise in the vicinity of airports.(ABSTRACT TRUNCATED AT 250 WORDS)