I am still reading the book "The Edge Effect" by Eric Braverman, MD.  This book focuses on the brain to improve health and longevity.  GABA is a neurotransmitter that helps to calm the brain.  According to the author, if you are experiencing a GABA deficiency, you may begin to feel anxious, nervous, or irritable.  Many of us experience these symptoms regularly due to stress, so of course, GABA would not be the only deficiency we may be experiencing.  Other indicators of a GABA deficiency from the book "The Edge Effect" are as follows:  Feelings of dread, blurred vision, protein cravings, cold or clammy hands, feeling of a lump in the throat, dizziness, TMJ, phobias, PMS, mood swings and more.  A lack of GABA can lead to numerous physical and mental health concerns.  If you find that you are struggling with personality, memory or attention issues, it may be worth checking out your GABA levels.  The author recommends adding foods with glutamine, which is a precursor of GABA to balance a GABA deficiency.  The following is the list of foods recommended:  Almonds, bananas, broccoli, brown rice, halibut, lentils, oats, oranges, potatoes, spinach, walnuts and whole wheat and whole grains.  Many times, if one neurotransmitter is deficient, others may also be deficient.  Many times, it is necessary to look at imbalances in the entire system in order to feel better, and improving our diets is a great place to start.  Have a great day!  Shanna