Neuroscience has an extreme heavy load to carry - every research in the field - from non-invasive, invasive, to natural realms are being explored and studied upon worldwide - and this takes months and years, through a carefully studied research. For every individual is unique, for all of us are like a snowflake, no two individuals are alike, so quite an accomplishment and feat it is.
Furthermore - it's not all genetics, mitochondrial, DNA, drug and/or alcohol abuse by the parent(s), there's also chemical and drug exposures, even going all the way up to "perfect parents" with no history of any background - finding that foods that they've been eating which contained toxins of all sorts, mercury, pollution, lead, poisoning, and even common everyday foods - peanuts, MSG, and so much more to add - that could possibility harm the unborn baby or even be damaging during the conception. Then you have those who had at one time or another who had done illegal drugs or were substance abusers or were both; and it carried over to the unborn baby which resulted damages to the development.
Then there are man-made damages; in which were caused to the child/teen/adult - such as head trauma which resulted injury or injuries - ranging from a motor vehicle accident to as simple as falling off from a chair.
In addition, there are diseases and illnesses that can create further problems, especially to a child. In addition, there's cases of what was "dormant" (gone away) after the child has become matured, then later on as an adult, suddenly it returns back to haunt them.
So much more, unknown reason, from all different directions and angles, many possibilities - a huge vast field for a Neuroscience field to accomplish and tackle.
For what appears to everyone as "Slow Going", when indeed is far from the truth, for if one looked outside at night and see all the stars in the Universe, Astronomers are still finding more unaccounted for! The brain is an amazing and yet, unique, fragile, and delicate, but awesome wonder - but it must be handled with care and approached in a very special way as not to endanger anyone's lives.
It takes months and years of careful studies and researches to come up with findings and conclusions, for 1 or 2 a case does not make when there are millions out there, however when there's 300 to 400 with positive response and results, that a case makes - and further research and studies proceed in such manner, such process is done in stages until they can prove that it, itself - works, before it is ever deemed finalized.
Patience is the key, but everyone loathes Epilepsy so much - the pressure is upon the Neuroscience to 'hurry up' and 'get going', however one cannot push into the depth of the brain, the very central nervous system that runs the human body - as implied, it must be handled with extreme care!
One day, it will come ... for indeed Neuroscience has progressed so much, far more than people have realized, however, I must put the emphasis on how much load is upon their shoulders that they must carry and what I have posted is only a trivial tidbit of the vast universe that they are undergoing!