Making use of auditory models for better mimicking of normal hearing processes with cochlear implants: first results with the SAM coding strategy

Stimulation based on auditory modeling, or SAM, is a new speech-processing strategy for cochlear implants that we developed recently at Fraunhofer IDMT. SAM incorporates active cochlear filtering along with the mechanoelectrical transduction of the inner hair cells, so that several psychoacoustic phenomena are accounted for inherently. SAM was tested with a group of five CI users: We investigated speech perception in quiet and in the presence of noise or reverberation, pitch discrimination abilities (for pure tones and sung vowels), and consonant discrimination. We also asked for subjective quality rating for speech and music snippets. Tests were repeated with the everyday strategy of the implantees and results were compared. This paper presents the test results in detail and compares outcomes with those of the previously published simulation studies. Results are encouraging, although more tests would be needed to increase statistical significance.