N-acetylaspartate, or NAA, is the acetylated form of the amino acid aspartate, and it is present exclusively in the nervous system. Indeed, NAA is one of the most highly concentrated chemicals found in the brain of humans and animals, and yet the functions served by this brain-specific metabolite remain elusive, and controversial. Despite the uncertainties surrounding the functions of NAA in the development and operation of the nervous system, this molecule has attracted the attention of researchers and clinicians for two distinct reasons.

First, the acetyl proton on NAA gives off...