["Central Recruitment" with unilateral conductive deafness (author's transl)]

Feldmann described a recruitment with conductive deafness using simultaneous tones for loudness-balancing. On 20 patients with unilateral conductive deafness a loudness-balance-test was performed in 4 different ways. The results were strongly method-influenced: 1 There was a substantial hysteresis between ascending and descending loudness-balancing. 2 The choice of the reference ear, i.e. the ear on which the intensity steps are fixed, appeared to be very important. Different results were obtained when the intensity steps were fixed on the good ear (and thus adapting for equal loudness on the bad ear) compared to the results when the intensity steps were fixed on the other ear.- With continuous tones, and when fixing the intensities on the good ear, a recruitment can be measured with conductive deafness, but it is only method-depending. For a reliable recruitment-diagnosis with the Fowler-test strictly defined test-conditions, considering method-depending influences, are necessary.