Sapporo radio personality Kazuya Yonezawa takes to the airwaves once a month, speaking to his listeners in a calm and low voice. But the 60-year-old's words aren't coming from his vocal cords.

They are being reconstructed by a speech synthesis software called Voistar.

Yonezawa has amyotrophic lateral sclerosis, the debilitating disease also known as Lou Gehrig's disease. ALS weakens the muscles and gradually deprives the body of all motor skills, including speech.