this is impressive.
His brain`s obviously on windows drivers with that latency…
cool vid though 
I was wondering about that too,
only possibility I could think of is being recorded may have made his brain more active.
I would guess that it takes quite a lot of thought to get your overall brainwave freq going up and down like that, so it`s not like you think up and you get a sudden response.
I guess the tech will improve over time though and be able to focus more on neurons firing rather than just overall brainwaves.
he used a toy from Mattel to get the “brain input” which already does all the job for him. I think he just connected the powermeter of the toy to the vintage synth. Probably it would be much more difficult to do with a modern one.
I’m also not sure this toy actually works with brainwaves: being headphone-shaped, it could even measure blood pressure, heat or something else which increases with thinking; this would also explain the delay
From what I can tell in the first video, he is using the fan voltage of the mindflex for VC on the Moog.
This is a feature of modern midi controllers that support foot controllers.
Earlier I read through a lot of comments on hackaday, Mindflex | Hackaday
The ear clips are apparently being used for grounding.
The chip is built from Neurosky, Neurosky has a few versions, the developer version with free API is $200 with a license of 1 year.
http://www.neurosky.com/mindset/devtools.html
But, looking through the agreement the 2nd year is $1,500