Yoshitaka Nakajima, PhD, President, Sound Corporation

A new hearing test for spectral-temporal resolution

Yoshitaka Nakajima, PhD, President, Sound Corporation

- Definition of business and contribution to society (whose products / services are provided)
Aiming at manufacturers of health check-ups that perform hearing tests and governments that provide public health services, early detection of hearing and brain disorders that may appear with age, etc. This will promote social participation of the elderly lengthening their healthy life expectancy.
This can contribute to the development of a new hearing aid utilizing an algorithm different from common acoustic processing.
- Technology outline (functions / performance, establishment status, presence / absence of existing technology and what are the advantages)
In a listening experiment with mosaic speech that changed the time resolution and the frequency resolution of speech signals independently, we found that, if either the time resolution or the frequency resolution is fixed and the other is sharpened, the intelligibility increases. This was confirmed. It has been considered that not only the simple sensitivity of the auditory system but also the time resolution and/or the frequency resolution are deteriorated in the elderly people. However, a stable measurement method for this has not been established. If mosaic speech is used, a simple hearing test can be performed.
- Marketability (how large and how many users can be expected in Japan and overseas)
Presbycusis / 15 million
Dementia / 4.67 million (2012 Ministry of Health, Labor and Welfare) expected to be 7 million in FY2018
- Proposer / team career / award history (what kind of experience / knowledge you can achieve)
Our company is a Kyushu University-based venture based on Nakajima's collaboration with researchers in Kyushu University, for which he worked until March, 2020.
It is a company that can transform the technical seeds centered around Kyushu University into evidence-based value that is useful to the society.

Yoshitaka Nakajima graduated in psychology from the University of Tokyo in 1978, and received a PhD in design at the Kyushu Institute of Design in 1999. After working for Osaka University, he worked for the Kyushu Institute of Design from 1984 to 2003, and technically moved to Kyushu University, which was merged with the Kyushu Institute of Design in 2003. He was appointed to professor in 2000. His research fields include auditory perception, time perception, music perception, phonology, and speech signal processing. He retired from Kyushu University in March 2020, and appointed to professor emeritus. He founded Sound Corporation with Akinori Oyama in April 2020.