FineHearing

A strategy is a plan with a clear destination. With cochlear implants, “getting from here to there” means creating the most effective blueprint for the conversion of sound into electrical signals that the brain can understand.

For years, coding strategies have only been able to represent one part of the sound, known as the “envelope” while improvements to the “fine structure” of sound have been limited by technological advancement. FineHearing™ from MED‑EL overcomes these limitations.
The “envelope approach” to implant development allows most users to achieve good levels of speech understanding in a quiet environment.1 Unfortunately, focusing on the envelope portion of sound alone cannot provide the best results for more complex hearing tasks.

Without the fine structure information, which gives each sound its own unique quality (e.g., musical pitch), cochlear implant users often report difficulty enjoying music and focusing on speech in noisy environments.2 Special settings for certain situations, such as focused listening, music, or soft sounds have not been an effective or convenient solution. In addition, languages that rely largely on changes in tone, or tonal languages such as Mandarin Chinese, have also been particularly challenging for cochlear implant users.

Elements of Sound

Envelope

The envelope is the “loudness contour” of the sound signal and is essential for speech understanding.

 
 

Fine Structure

The fine structure contains the subtle details of a sound signal and enhances pitch and sound quality.

Studies demonstrate that fine structure is the main information carrier for music and sound localisation.3 With FineHearing technology and Complete Cochlear Coverage, users can benefit from enhanced sound coding that represents both parts of the sound, the envelope and the fine structure. Unlike traditional sound processing, MAESTRO uses a highly advanced algorithm, known as the Hilbert Transform, to provide high-definition digital signal processing that closely extracts the overall shape, or envelope, of an incoming sound with a high degree of accuracy. In addition, special patented electrical pulses are presented to the apex of the cochlea, using a unique pulse shape that carries the tone and quality information. In this way, the fine structure of the sound is also presented with great accuracy to provide unprecedented sound quality.

Fine Structure Processing, an implementation of FineHearing technology from MED‑EL, offers users a new level of sound quality,3 especially when listening to music, by offering both the envelope and the fine structure sound information.
  1. Helms J. Comparison of the TEMPO+ ear-level speech processor and the CIS PRO+ body-worn processor in adult MED-EL cochlear implant users. ORL Head Neck Surg 2001; 63: 31-40.
  2. Nopp P, Polak M. From electric acoustic stimulation to improved sound coding in cochlear implants. Accepted for publication in: van de Heyning P (ed), Cochlear Implant and Hearing Preservation, Karger.
  3. Smith et al. Chimaeric sounds reveal dichotomies in auditory perception. Nature; 2002; 416: 87-90.

© 2017 MED-EL