Part of the underside of the brain that includes the anterior frontier/caudal area of the midbrain (telencephalon).
Basal forebrain includes the nucleus accumbens (ventral striatum), ventral pallidum, septal region, substantia innominata with nucleus basalis Meynert (acetylcholine-producing), the caudal nucleus of the striated and Broca's diagonal band with nuclei and tuberculum olfactorium with contents.