a hereditary or later obtained disease, marked by a lack of capacity within the body to carry or use specific amino acids. This generally results from an inexistence of certain enzymes which are essential to performance or transporting amino acids and their common part throughout the cycle of metabolism. There are over eighty types of amino acid instabilities, a large amount of which impact the CNS.

AMINO ACID IMBALANCE: "An amino acid imbalance can cause several disturbances to human function, including but not limited to cognitive repercussions."