Try this out. See, if this get's the blood running to your brain. But, do not do this standing up or operating a machine. You must be sitting down.
1. Take 20 deep breaths.
2. On, the 20th breath, take in as much air as you can. Hold it with your head tilted back and eyes looking up.
3. When you start to get a feeling in your head, release the air, and lean forward with your head toward the ground. Basically, the position is your head between your knees. Or, for safety reason, you might want to lay down.
Now, that's a high. Oxygen rushing toward your brian.
This technique can make your pass out. And, I don't know if it's even good for you. Personally, I feel it very good for the brian.
If, you feel that the feeling is strong. When you release your air, lay down as soon as possible.
If you try this out let me know what kind of feels come over you. Some times, I get a strong vibration feeling all over my body, and it bring a feeling of pleasure.