Born 1946 in Tokyo, based in Kanagawa prefecture (Japan).

During the nationwide student protests, Hikosaka was at Tama Art University, and became one of the Bikyoto artists who produced exhibitions inside the barricaded university. Building on his works from that time, in the 1970s his "Floor Event" exhibitions involved pouring large amounts of latex onto a tatami-mat room at his home. He also created his Wood Painting series during this period. Inspired by Lacan's psychoanalysis, he constructed a theory of art analysis, presenting it through his blog. Hikosaka's deep interest in history led to conceiving his continuous Art Studies symposium. In 2009, he became a Specially Appointed Professor at Rikkyo University. Recent projects, such as his 《Imaginary Museum of the Imperial Palace》 (2010) have come about through links with people in the field of architecture. Hikosaka took refuge in Kyoto following the 2011 Tohoku earthquake and tsunami, but he drew graffiti in the form of pictorial versions of the characters for restoration or resurrection on the walls for a meeting area tower in a camp for temporary homes in Minamisoma, Fukushima prefecture. This is the only temporary housing to incorporate art from the design stage. Hikosaka also collected waka poems by people affected by the disaster, publishing them as March 11 Man'yoshu FUKUSHIMA—Tower of the Resurrection (2012).