Research into brain injuries has been ongoing, but tended to focus more on direct impacts. In the last 70 years there has been more research into rotational brain injuries, and in the 1990s and 2000s scientific, evidence based proposals were made to reduce these. The Multi-Directional Impact Protection System is an implementation of these, and it's effectiveness has been validated by independent research.
There is lots of research into brain injury. While much of it has focused on direct impact leading to scull fracture, the effects of sudden head rotation have been studied since the 1940s. These (pay-walled papers) are typical
Such studies progressed to proposals, such as
[In] 2008 ... Swedish neurosurgeon Hans Von Holst, along with mechanical engineer Peter Halldin, developed a new technology called MIPS (Multi-Directional Impact Protection System).
A couple of (non independent) articles are
Mips has been received with acclaim
There has been at least one study of their effectiveness
But not everyone is convinced regarding helmet effectiveness. For a helmet skeptic's view see
Certainly, more independent validation would be good, and in future better designs could appear. At present MIPS seems to set the brain protection benchmark.