New research partly funded by an RNID Discovery Research Grant suggests that cochlear implant devices could be made smaller or last much longer without recharging – without reducing how well users understand speech in noisy environments.
The study, led by Dr Lidea Shahidi, Dr Bob Carlyon and Dr Tobias Goehring at the University of Cambridge, tested a sound processing approach that could cut the power used by cochlear implants by up to 42%. Crucially, the researchers found that these energy savings did not come at the cost of poorer speech understanding in background noise.
Why longer‑lasting cochlear implants could improve daily life
Cochlear implants help people with severe or profound deafness to hear by sending electrical signals directly to the auditory nerve. To do this, implants break sound down into different channels and deliver rapid pulses of electrical stimulation. The way a cochlear implant does this is known as its ‘Sound Processing Strategy’.
While cochlear implants can be life‑changing, many users still find it difficult to understand speech in noisy places such as cafés, workplaces or classrooms. At the same time, many improvements to sound processing require more power, which can limit battery life or require larger batteries and more frequent charging.
Finding ways to reduce background noise and cut power use without harming listening performance could make a real difference for the one million people worldwide who use a cochlear implant.
About the study
The team evaluated a technique known as the Temporal Integrator Processing Strategy (TIPS). This method simplifies the pattern of electrical signals sent by the implant by removing signals that are unlikely to be heard by the user.
In this study, the researchers tested TIPS under more realistic listening conditions than previous work. Participants took part in experiments that compared TIPS with standard, clinically used sound processing strategies while listening to speech in different types of background noise.
What the results show
The results were mixed – but encouraging.
On average, TIPS did not improve speech understanding in noise, but crucially it also did not make it worse, even in challenging listening environments. There were individual differences between participants, with some people showing small improvements.
What stood out most was energy efficiency. Depending on the configuration used, TIPS reduced power consumption by between 21% and 42%.
What this research could mean for future cochlear implants
Energy saving could have major implications for the future of cochlear implant technology. Using less power could allow devices to:
- last longer between charges
- use smaller or lighter batteries
- free up energy for more advanced processing, such as AI‑based noise reduction
Although this study did not show clear improvements in speech understanding for all participants, the findings are encouraging. They suggest that sound‑processing strategies that simplify cochlear implant signals can save substantial energy without reducing listening performance.
The researchers are now continuing to refine the strategy, with the long‑term goal of combining better sound quality with lower power use, which could significantly improve everyday life for cochlear implant users.
The study has been selected as an Editor’s Choice paper in the journal, Ear & Hearing, highlighting its importance to the field.
