Dopamine is a neurotransmitter (chemical messenger) synthesized by your body and brain cells from the dietary intake of an amino acid called tyrosine. This amino acid is found in protein-rich foods such as chicken, milk-based products & meat. Dopamine is also a precursor to two other important neurotransmitters called adrenaline and noradrenaline (also called : epinephrine and norepinephrine). Your brain -nervous system- uses these neurotransmitters to send various messages in the form of electronic impulses throughout your body, thus regulating all of the body's functions.
Dopamine regulates a variety of functions within your brain & body. How? Well, it has many functions but most commonly it helps to regulate blood flow through the arteries (involved in hypertension issues), modulates additions & eating habits, contributes to high cognitive functioning and learning (involved in ADHD issues), regulates motor activity (involved in Parkinson disease), etc...
Serotonin is an other neurotransmitter released by brain's neurons, more specifically in the pineal-gland. Various effects of serotonin seem not related. That's why this neurotransmitter one of the most complex in the body. Serotonin is synthesized by the body through an amino acid called l-tryptophane, found in protein-rich foods such as chicken, milk, turkey and also bananas. Adequate sleep, exercise and certain drugs can all significantly raise serotonin levels in the body.
Serotonin has a profound effect on mood. That's why it called "the happiness molecule". Increased serotonin's levels lead to the capacity to withstand everyday stress and a cheerful disposition. Many studies have found that depression syndroms can highly result from chronically low serotonin levels. There are many other mental & brain disorders linked to low serotonin levels including anorexia, social anxiety, phobias, obsessive-compulsive disorder, bulimia, body dysmorphic disorder and bipolar disorder .
Noradrenaline and adrenaline -also called Norepinephrine & epinephrine- are catecholamines that play significantly major functions in regulation of the "inner world" of the body by the nervous system (brain). Norepinephrine (synonymous with noradrenaline), the main neurotransmitter of the sympathetic nervous system, is responsible for reflexive and tonic variations in cardiovascular tone. Adrenaline -synonymous with epinephrine- is a key determinant of global challenges or responses to metabolic homeostasis, such as manifestations of emotional distress, and of privation of glucose.
GABA is a neurotransmitter -chemical messenger- that is widely distributed in the brain. In contrast to glutamate or adrenaline, the natural function of GABA is to decrease the activity of the neurons to which it binds. It controls the anxiety or fear experienced when neurons are overexcited, often caused by a higher glutamate activity. When an abundance of stress and tension occurs in the brain, it can be caused by an excess of glutamate, adrenaline or noradrenaline. To counterbalance this extra, the nervous system produces inhibitory brain chemical (neurotransmitters) -one of which is GABA- that have inhibitory effects upon the brain system.
Acetylcholine is an other neurotransmitter which plays a critical part in logicial & verbal reasoning, the formation of memories, and the ability to learn and concentrate. It is a neurotransmitter that is highly involved in Alzheimer's disease. This chemical messenger also offers significant protective benefits and it may also limit the neurological decay associated with nervous system degenerative diseases (such as Alzheimer's).
Glutamate is linked to increased learning and memory. The brain requires a perfect balance between glutamate and gaba levels (as seen above) in the brain to facilitate learning and memory. Overall nervous system functions depend on optimal levels of GABA and glutamate. There should be adequate amounts but not an overabundance or a deficiency.