The basal nuclei utilize a wide range of neurotransmitters: GABA (gamma amino butyric acid) and dopamine are inhibitory neurotransmitters. Ach, norepinephrine, serotonin, and enkephalin are found in connecting pathways, both excitatory and inhibitory, to other areas, and there are multiple glutamate pathways which provide most of the excitatory signals within the basal nuclei.