In the normal mammalian ear, sound vibrates the eardrum, causing the tiny bones of the middle ear to vibrate, transferring the vibration to the inner ear fluids. The vibration propagates from the base of the cochlea to its apex along the cochlear partition. As essential as this concept is to the theory of hearing, the waveform of cochlear partition vibration has yet to be measured in vivo. Here...

INTRODUCTION  Few cases of cochlear implantation (CI) in neurofibromatosis type 2 (NF2) patients had been reported in the literature. The approaches described were translabyrinthine, retrosigmoid or middle cranial fossa. OBJECTIVES  To describe a case of a NF2- deafened-patient who underwent to vestibular schwannoma resection via RLA with cochlear nerve preservation and CI through the round w...

UNLABELLED Cochlear implants are the best treatment for congenital profound deafness. Pediatric candidates to implantation are seen as vulnerable citizens, and the decision of implanting cochlear devices is ultimately in the hands of their parents/guardians. The Brazilian Penal Code dictates that deaf people may enjoy diminished criminal capacity. Many are the bioethical controversies around co...

Most models of the cochlea developed during the last decade have explained frequency selectivity and sensitivity of the cochlea at threshold by the use of power amplification of the acoustic wave on the basilar membrane. This power amplification has been referred to as the cochlear amplifier (CA). In this paper, a method to measure the cochlear amplifier gain as a function of position along the...

It has traditionally been assumed that cochlear implant users de facto perform atypically in audiovisual tasks. However, a recent study that combined an auditory task with visual distractors suggests that only those cochlear implant users that are not proficient at recognizing speech sounds might show abnormal audiovisual interactions. The present study aims at reinforcing this notion by invest...

The mammalian auditory sensory epithelium, the organ of Corti, is a highly ordered cellular structure that comprises two types of auditory hair cells and several types of nonsensory supporting cells. During embryogenesis, a stereotyped sequence of cellular and molecular events is required for its development. These processes are assumed to be regulated by multiple growth and transcription facto...

This investigation examined the effects of loud sound of different frequencies and intensities on cochlear blood flow as measured by the laser Doppler flowmeter. Cochlear blood flow was measured in anesthetized guinea pigs during a 1 h exposure to either a 2, 4, or 12 kHz pure tone or high-pass noise (10-40 kHz) at 90, 103, or 110 dB SPL. Cochlear function was assessed using the compound action...

BACKGROUND The occurence of cholesteatoma and cochlear implant is rare. Secondary cholesteatomas may develop as a result of cochlear implant surgery. Primarily acquired cholesteatoma is not typically associated with congenital sensorineural hearing loss or cochlear implant in children. The occurrence of congenital cholesteatoma during cochlear implant surgery has never been reported before, par...

Cochlear implant devices are designed to provide sound sensation and improved speech understanding to people who are profoundly hearing impaired. Best speech recognition could be achieved by using multi-channel, multi-electrode cochlear implant devices. In a multichannel cochlear prosthesis, channel interaction and tissue damage are important issues to be solved. Speech processing and modidatio...

The conventional theory about the snail shell shape of the mammalian cochlea is that it evolved essentially and perhaps solely to conserve space inside the skull. Recently, a theory proposed that the spiral's graded curvature enhances the cochlea's mechanical response to low frequencies. This article provides a multispecies analysis of cochlear shape to test this theory and demonstrates that th...