All Categories - EAR Lab

New paper showing differences between rate and place coding in the first and second cochlear turns

12/9/2018

Landsberger, D. M., Marozeau, J., Mertens, G., and Van de Heyning, P. (2018). "The relationship between time and place coding with cochlear implants with long electrode arrays," The Journal of the Acoustical Society of America 144, EL509-EL514.

Download here.

New paper comparing Analog to Pulsatile stimulation with a cochlear implant

11/1/2018

Curious about the sound differences between these three different ways of presenting 100 Hz on a single electrode of a cochlear implant? If so, read our new paper:

Stupak, N., Padilla, M., Morse, R. P., and Landsberger, D. M. (2018). "Perceptual Differences Between Low-Frequency Analog and Pulsatile Stimulation as Shown by Single- and Multidimensional Scaling," Trends in Hearing 22, pdf

New paper suggests that alternating polarity of pulses requires less current to maintain loudness than a constant polarity order.

8/14/2018

We have a new paper out that demonstrates a method of reducing power requirements to reach a comfortable loudness with a cochlear implant. If implemented in a cochlear implant sound processing strategy, it could potentially lead to significant battery savings.

Todd, A. E., and Landsberger, D. M. (2018). "The effect of polarity order and electrode-activation order on loudness in cochlear implant users," The Journal of the Acoustical Society of America 144, EL112-EL118. pdf

Removing Background Talkers: New Demo of SEDA iOS Noise Reduction Algorithm Prototype

7/25/2018

We have built the very first prototype of the SEDA noise reduction algorithm for Apple iOS devices. SEDA is designed to remove background noise consisting of other people talking. This version of the algorithm runs real-time with a latency of approximately 15 ms.

We are in the process of formally evaluating the prototype. While these results are not yet in, we think the algorithm sounds like it works well. Take a listen to an example yourself in the above video.

We can remove the noise of other people talking in the background to help cochlear implant users understand speech in noise!

12/9/2017

Roozbeh Soleymani of the EAR Lab has developed a noise reduction algorithm named SEDA which is specifically designed to reduce "multi-talker babble" noise (i.e. the noise of other people talking in the background. Average improvement for CI users was between 7 and 18 percentage points more words (depending on the signal to noise ratio) on the very difficult IEEE sentence test. Additionally, all CI users rated the sound quality of speech processed with our SEDA noise reduction as having a better sound quality than without it.

Speech intelligibility of IEEE sentences in multi-talker babble with (blue) and without (red) SEDA processing averaged across 7 subjects. The purple dashed line indicates performance for the subject in quiet, representing the best possible score for that subject.

For more information, check out the article (downloadable below) or the SEDA webpage.

Soleymani, R., Selesnick, I. W., and Landsberger, D. M. (2018). "SEDA: A tunable Q-factor wavelet-based noise reduction algorithm for multi-talker babble," Speech Communication 96, 102-115. pdf

New paper suggests that musical pitch information is not adequately provided by temporal information for cochlear-implant or normal-hearing listeners.

11/22/2017

We have a new paper out in Trends in Hearing. In this paper, we played a song (Happy Birthday) using temporal information only to both cochlear-implant (CI) and normal-hearing (NH) listeners. Both groups were insensitive to changes in tuning (i.e. if the melody was played in or out of tune) when played using only temporal information. However, listeners were highly sensitive to changes in tuning when played using pure tones (i.e. with both temporal and place information). These results suggest that temporal coding of pitch is insufficient to convey proper musical intervals. Furthermore, listeners with a CI in one ear and NH in the other performed like NH listeners with the NH ear and CI listeners with the implanted ear, suggesting that the limitations in CI performance are not related to CI listeners’ lack of familiarity with music perception.

Todd, A. E., Mertens, G., Van de Heyning, P., and Landsberger, D. M. (2017). "Encoding a Melody Using Only Temporal Information for Cochlear-Implant and Normal-Hearing Listeners," Trends in Hearing 21. pdf

New Paper on Research Interfaces for Cochlear Implants

11/11/2017

We've got a new paper out on the use of research interfaces with cochlear implants. Its also my first paper with Ruth Litovsky, Matt Goupell, and Alan Kan.

Litovsky, R. Y., Goupell, M. J., Kan, A., and Landsberger, D. M. (2017). "Use of Research Interfaces for Psychophysical Studies With Cochlear-Implant Users," Trends in hearing 21. pdf

A cool note from the Listen Lab at the University of Washington.

11/11/2017

We received this really cool "Thank You" note from Matt Winn and the Listen Lab at the University of Washington. I love the handshake / high five between the Listen Lab mascot (left) and the Ear-Lab mascot (right). I've been meaning to post this for quite a while now.

Back from APSCI 2017 (Asia Pacific Symposium on Cochlear Implants)

9/26/2017

Back from a quick trip to Cyprus. David Landsberger gave a key-note talk on pitch perception. Now two weeks at home and off to Los Angeles!

New Paper: Determining the Minimum Number of Electrodes That Need To Be Pitch Matched to Accurately Estimate Pitch Matches Across the Array.

7/15/2017

We've got a new paper out from our collaboration with Justin Aronoff and Julia Stelmach from the Binaural Hearing Lab at the University of Illinois.

In this paper, we found that nine pitch matches are sufficient for accurately determining pitch matches across the array. This requires approximately 7 min of testing, indicating that accurate pitch matching can be accomplished in a clinically feasible timeframe.