Before revision: Types Inhibitory amino acids (IAA) inhibitory amino acids (IAA) depress the activity of post-synaptic cells.
After revision: Amino acid Excitatory or inhibitory Aspartic acid Excitatory Cysteine Excitatory β-alanine Inhibitory GABA (adult human brain) Inhibitory (adult); excitatory (developing) Glycine Inhibitory Glutamic acid ExcitatoryTypes Inhibitory amino acids (IAA) inhibitory amino acids (IAA) depress the activity of post-synaptic cells.