Getting to Know Your Brain Chemicalsby Jerry Kennard, Ph.D. Medical Reviewer
Many of our moods depend on our nervous system. Too much or too little of the chemicals that speed things up or slow things down and the whole thing can go out of kilter. The basis of many of our medications is to correct these imbalances. In this Sharepost I'm taking a look at just a handful of the essential neurotransmitters and the way they work?
Glutamate and GABA can be thought of as mainstay neurotransmitters. They slog away in high concentrations within the brain where one (glutamate) is the throttle and the other (GABA) acts as the brake. Glutamate has an important role in learning and memory but too much and it can lead to agitation, impulsive behavior and even violence. GABA has the opposite effect. It increases our levels of tranquility by inhibiting too much nerve activity. Some of the most frequently used drugs for anxiety enhance the action of GABA.
Serotonin is all about serenity and hopefulness in moods. The latest generation of SSRI drugs, such as Prozac, aim to increase levels of serotonin within the brain. Low levels of serotonin are associated with depression.
Dopamine is our arousal and stimulation neurotransmitter. We associate dopamine with rewards as it controls our appetite for sex, eating, pleasure and even creative thinking. Too little dopamine can lead to depression but too much can lead to dependence on the agent doing the stimulating. Cocaine, for example, increases dopamine levels in the brain's reward circuit and, for a period, can produce intense pleasure. Long-term use seems to result in neural degeneration from overproduction of dopamine.
Endorphins are both hormones and neurotransmitters and they can pack a punch. We have at least 20 different types of endorphin some of which are more powerful than morphine. We tend to release endorphins when we're under stress or in pain. The higher the level of endorphin the less pain we feel and the more relaxed, even euphoric, we can become. Foods like chocolate or chilli peppers enhance the secretion of endorphins. Perhaps it isn't surprising that we associate chocolate with comfort and pleasure.
Noradrenaline (norepinephrine) is the main neurotransmitter of the sympathetic nervous system. We associate this with our fight-or-flight mechanism and moderation of other physical actions such as heart rate and blood pressure. Too little noradrenaline and we become sleepy and lethargic. Too much and our thoughts run away with us, we become twitchy and nervous, our hands and feet go cold and our blood pressure climbs.