I don't know if we've seen real benefits from NT yet, but I can say definitively that the electrodes the nurse connects to Ryan's head do stimulate his brain in some way.
I know this because the nurse found Ryan's Reset button.
After a week or more of what I thought was clear progress, Nurse Brainley announced she was going to start treating a different section of Ryan's brain - the P4, for those following along at home. This bit has something to do with socialization, so I was instructed to make note of whether Ryan became more or less interactive.
Answer: he instantly regressed by several months.
Suddenly, there were meltdowns in places we hadn't seen meltdowns since the winter. All at once, Ryan was declaring the single word "Tummy!" instead of "My tummy hurts/I'm hungry/There's something wrong somewhere and I'm going to localize the problem in my tummy."
And then the nurse went back to poking the previous region of Ryan's brain, and everything was fine again.
Don't mess with the reset button.