(Neurotransmitters ) ▶Glutamate and aspartate. These amino acids are the major excitatory neurotransmitters in the CNS. ▶Gamma-aminobutyric acid. (GABA) is the major inhibitory neurotransmitter in the brain. ... ▶Serotonin. ▶Acetylcholine. ▶Dopamine. ▶Norepinephrine.