- Expertise：Violin, Viola
While studying at Toho Gakuen School of Music, Toyoshima began performing as a soloist on both the violin and viola, as well as performing chamber music and as a concertmaster. In 1986 he was appointed principal concertmaster for the New Japan Philharmonic. As soloist, he has performed together with the many Japanese and international orchestras. At present he is concertmaster of the Hyogo Performing Arts Center Orchestra, solo concertmaster of the New Japan Philharmonic, and concertmaster laureate of the Kyushu Symphony Orchestra, a member of Alti String Quartet.