Brain function and thought patterns are intimately related to neurotransmitters, the chemical messengers that carry signals between neurons, or nerve cells, and other cells within the body. Neurotransmitters are essential for various physical and psychological functions including mood, anxiety, fear, joy, and happiness. They are also involved in regulating heart rate, sleep, and appetite.
There are two classifications of neurotransmitters that are named based on their effect on the brain: excitatory and inhibitory. Excitatory neurotransmitters have an excitatory effect on the neurons. They cause the neuron to fire an electrical signal called an "action potential" up the cell. Some common excitatory neurotransmitters are epinephrine, norepinephrine, dopamine, acetylcholine, and serotonin.
How Are Neurotransmitters Produced in the Body?Most neurotransmitter production begins with an amino acid from the diet or another chemical that's already present in the body. Different amino acids are precursors for different neurotransmitters and the receptors to which they bind. Enzymes and various nutrients are required to convert these amino acids into neurotransmitters. B vitamins, vitamin D, minerals, and other compounds play a critical role in brain health to manufacture all neurotransmitters.
It's worth mentioning that genetic variants can stop the production of these enzymes needed to make neurotransmitters.
AcetylcholineOne of the primary roles of acetylcholine in the central nervous system is to promote cognition, memory, and arousal. It's also involved in peripheral nervous system function and is used to activate muscles.
A deficiency in acetylcholine would look like a decrease in visual and verbal memory as well as frequent memory lapses. Individuals needing acetylcholine support might notice a decline in creativity or comprehension. Difficulty calculating numbers or recognizing objects and faces are also indicative of an acetylcholine issue.
CatecholaminesEpinephrine and norepinephrine are in a class of neurotransmitters called catecholamines. Technically, dopamine also falls into the catecholamine class, although dopamine will be discussed separately because of its different physiological effects. Additionally, take note that epinephrine and norepinephrine are also called adrenaline and noradrenaline.
Epinephrine and norepinephrine are involved with the body’s “fight-or-flight” response. When released into the bloodstream, they increase heart rate, pupil dilation, and shunt blood to muscles. In the brain, they stimulate receptors for mental speed, focus, and concentration. Likewise, a catecholamine deficiency might look like a reduction in mental alertness, speed, concentration, and cognition.
DopamineDopamine has various functions in the brain including motor coordination, mood, attention, learning, along with motivation and reward. It's largely associated with the pleasure system of the brain.
Individuals with dopamine imbalances may experience feelings of worthlessness or hopelessness, or self-destructive thoughts. They often have an inability to handle stress and may feel angry while under stress. They sometimes desire isolation or have a lack of concern for loved ones.
SerotoninAlso known as the “happiness neurotransmitter,” serotonin is found in both the central and peripheral nervous systems and is involved with mood, sleep, temperature regulation, and appetite. In fact, roughly 80 to 90 percent of the body’s serotonin production occurs in the gut.
Those with serotonin deficiencies often feel a loss of pleasure in their hobbies, interests, relationships, and favorite foods. They might have trouble falling asleep at night. Individuals with serotonin deficiencies sometimes have a strong dependency on others. Often, they can experience feelings of paranoia, rage, unprovoked anger, or sadness for no reason. Women with serotonin problems often suffer from premenstrual syndrome.