Question

What is the most common neurotransmitter?

Answer 1

The most prevalent transmitter is glutamate, which is excitatory at well over 90% of the synapses in the human brain. The next most prevalent is Gamma-Aminobutyric Acid, or GABA, which is inhibitory at more than 90% of the synapses that do not use glutamate.

Answer 2

Glutamate is the most common neurotransmitter in the brain.