DRD2 and schizophrenia: The salience dysregulation in schizophrenia (Winton-Brown et al., 2014) appears linked to hyperactivity in the meso-limbic DA neurons (Grace, 2017) and to deficient brakes on D2R protomer signaling in its inhibition of the ventral-striato-pallidal anti-reward system involving inter alia multiple A2AR-D2R heteroreceptor complexes.