Since the first French flight in space in 1982, the CNES has developed a wide range of instruments, especially in the field of Neurosciences. The design of these instruments has considerably evolved from rather simple equipment up to much more sophisticated tools that are being specially tailored for these missions. Four major phases can be identified: -a simple adaptation of an echographe leading to the first neurosciences experiments (the ARAGATZ'88 mission), -the ILLUSIONS and VIMINAL instruments used during the ANTARES'92 and ALTAIR'93 missions, -the COGNILAB instrument developed for the CASSIOPEE'96 mission, to be re-used in 1997 and in 1999, -a preliminary design of the 1999 mission payload, including virtual reality concepts, in a modular design to adapt to the European COF. Aside from the evolution of scientific requirements, the experience gained during the flights led to progressive improvements in the different technical parts, including visual system, body restraint systems, accessories, such as a force feedback joystick, computer and software, etc. This paper describes the technical evolutions in the CNES Neurosciences program.