The importance that early auditory stimulation has on the infant's plastic brain with regard to optimal listening and language development is well-known. 1,2 During the first year of life, infants with normal hearing start to pay attention to the acoustic features of the speech they are surrounded by. They also develop phonology and acquire the statistical patterns that are important for word segmentation. 3 Children with congenital hearing loss are now identified earlier because of universal hearing screening programmes for newborn infants. 4 The recommended practice for newborn infants with hearing

Otosclerosis is a common disorder that leads to conductive hearing loss. Most patients with otosclerosis also have tinnitus, and surgical treatment is known to improve hearing as well as tinnitus. Some patients however experience worsening of tinnitus after the operation, but there are no known factors that allow surgeons to predict who will be at risk. In this prospective observational study on 133 patients undergoing stapedotomy, we show that postoperative air conduction thresholds at very high stimulus frequencies predict improvement of tinnitus, as assessed with proportional odds logistic regression models. Young patients were significantly more likely to experience reduction of tinnitus and patients whose tinnitus became better were also more satisfied with the outcome of the operation. These findings have practical importance for patients and their surgeons. Young patients can be advised that surgery is likely to be beneficial for their tinnitus, but a less positive message should be conveyed to older patients.Otosclerosis is a common disorder 1,2 , where one of the ossicles in the middle ear, the stapes, gradually fuses with surrounding bone, producing conductive hearing loss. This hearing impairment can be treated surgically 3 , commonly by replacing the diseased stapes with a prosthesis that improves sound transmission through the middle ear to the sensory cells in the inner ear. The usual result is great enhancement of low-frequency hearing 4 . At frequencies below 1000 Hz, the average improvement is around 30 dB, which substantially enhances speech perception and frequently means patients no longer need hearing aids.Despite being a generally successful procedure that improves hearing in a large majority of patients, stapes surgery is associated with some risk. The risk for complete hearing loss on the operated ear is very low, on the order of 1% 5 . However, many studies have shown that the benefit from surgery declines with stimulus frequency and at 6 and 8 kHz, some loss of both air and bone conduction thresholds is commonly seen [6][7][8][9] . In two previous studies 10,11 , where the frequency range of audiometry was extended beyond the standard 8 kHz, a mean threshold loss ranging from 9 to 23 dB was evident across the frequencies 10-14 kHz, despite robust improvement of low-frequency hearing. The relevance of changes in hearing thresholds at these very high stimulus frequencies is unclear, although tinnitus patients often have elevated thresholds at 10 kHz and higher, which may correlate with the pitch of their tinnitus 12 .

A new method was developed for continuous measurement of the middle ear pressure during a 24-h period. The equipment consisted of a piezo-electric pressure device and a digital memory. To allow continuous pressure recordings during normal every-day activities the equipment was made light and portable. The measurement accuracy of the equipment as well as the base-line and temperature stability were tested and found to meet to our requirements satisfactorily. In 4 volunteers with different middle ear conditions, a small perforation was made through the tympanic membrane. A rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Tubal function tests were made to establish the equipment's ability to monitor fast pressure changes. The tests were well in accordance with other methods of direct pressure measurements. The equipment was carried by the volunteers for 24 h to monitor any slow or rapid dynamic pressure changes in the middle ear. Four continuous 24-h measurements are presented. The method was found to be suitable for valid measurements of dynamic pressure changes in the middle ear during normal every-day activities. It may become a useful instrument in the search for a better understanding of the development of chronic middle ear disease.