Various studies have shown that ozone therapy can reverse the effects of a stroke, but the ozone must be administered within about 3 hours of the stroke. The reason is that much of the damage from strokes occurs from enzymes released after the stroke. The ozone destroys these destructive enzymes.
Still the ozone could help with increasing brain function so I would still recommend it.
The most effective way of getting ozone in to the brain is through the ear. The person lays on their side and places the output tube from the machine near the opening of the ear so the ozone blows in to the ear canal under low pressure. Ozone weighs more than air so it will sink in to the ear canal. This is why the person lies on their side. It is also a good idea to have a fan blowing gently in your face to keep the ozone away from your face. Inhaling high concentrations of ozone is not good. Recommended length of time for use is 20 minutes three to 4 times daily.
I discuss the different types of ozone units here:
http://curezone.com/forums/fm.asp?i=1495716#i
Overall cold corona units are the best. But they are also the most expensive and hardest to find units. On average they will run $1500 to $15,000. Many manufacturers I have seen claim their units are cold corona when in fact they are hot corona. Unfortunately it is impossible to say what they are without actually looking at the internal workings to see how they are made.
For what you you will be doing through you can get by with a hot corona unit, which are readily available. These can be used externally and with an air source instead of oxygen as long as you stick to external use and do not use a high power. If you do have an oxygen source even for a hot corona this is still better.
I do not know of any manufacturers of true cold corona devices off hand. I see them on Ebay once in a while.