EEG-responses caused by environmental noise during sleep their relationships to exogenic and endogenic influences.

At a certain level of intensity acoustical stimuli occurring during the night lead to sleep disorders. Whereas presumed after-effects (decrease of performance, functional and organic diseases) can as yet not be related to noise, it is evident that the primary effects which can be recorded immediately after stimulus onset are caused by noise. Because of the small number of experimental trials carried out in different investigations, the results of each single paper can only be tentative. Therefore--concerning awakening reactions and less than a change of at least one sleep stage--the data from publications of comparable method and evaluation have been summarised. With these data all calculations have been repeated. The results and influence of several exogenic and endogenic factos are demonstrated. Becuase of the different methods used only 10 out of 60 publications have been used. In spite of this restriction of data, at least as far as trends are concerned, they appear to be consistent; numerical results should at this stage only be regarded as tentative.