Neurotransmitters
Neurotransmitters are messenger molecules used by brain cells or neurons. They
are critical to brain functioning, and since the brain controls almost every
function in the body, they're vital to health too. Most mind-altering drugs work
by influencing neurotransmitter balance. Most mental and neurological illnesses
involve disruption of neurotransmitter balance.
There are different types of neurotransmitter:
- excitatory - when an excitatory neurotransmitter arrives at a neuron, it is more
likely to fire its output. The main excitatory neurotransmitter in the brain is
glutamate.
- inhibitory - by contrast inhibitory neurotransmitters tend to stop firing or
turn off output. The brain's main inhibitory neurotransmitter is GABA. Boosting
brain levels of GABA tends to be calming (e.g. alcohol does it!)
- neuromodulators - these work not directly as messengers but rather change or
modulate the way neurons to incoming signals. Examples include serotonin and
dopamine.
Amino Acids
All the major neurotransmitters either are, or are made from, amino acids. We
get our amino acids from protein in the diet.