[About the influence of body posture on the result of acoustical examinations (author's transl)].

Effect of socalled tonic reflexes on central processing of acoustic stimuli was studied by stimulating the patterns of tonic reflexes in 18 adults with normal hearing abilities. The parameters were: hearing threshold level, acoustical stapedius reflex and slow auditory evoked potential. Only in three positions-corresponding to the symmetrical tonic neck reflex (STNR) and tonic labyrinthine reflex in supine and prone position a hearing threshold shift of 1 dB could be observed. The level of the stapedius reflex showed an increase of 5 dB in one of these three positions. In the acoustical evoked slow potential only the amplitude but not the latency was influenced. In some cases we found an increase of amplitude, in others a decrease or even a complete suppression. In using ERA to evaluate possible auditory disturbances in children with cerebral palsy it seems necessary to consider these possible influences on the evoked potential.