In my opinion, all you can really do is get a solid diet and make sure you're getting ample rest... same as with any overtraining conditions. Stimulants will probably burn you out even faster, though you may feel better temporarily. The CNS is a weird thing but time, rest, and good general nutrition is the only thing I know to aid in recovery of it.
Here's a thread that was posted a long time ago in S&P. The question is near identical to yours. Although, nothing was really cleared up as far as nutrition goes... ENTROPY's post on page 2 is still more than worth the read.
Food and nutrient for the central nervous system.