The term ventrolateral periaqueductal gray refers to one of four longitudinal cell columns in the periaqueductal gray that surrounds the cerebral aqueduct in the midbrain tegmentum. Revealed best by stain for nitiric oxide synthase (NADPH-diaphorase), it is found in the human, macaque, rat ( Carrive-2012 ), and mouse ( Franklin-2008 ). Located ventral to the lateral periaqueductal gray column and ventrolateral to the cerebral aqueduct, it also stains lightly. The other two columns are the lightly staining dorsomedial periaqueductal gray and the heavily staining dorsolateral periaqueductal gray. Functionally all four columns belong to the motor periaqueductal gray of the behavior control column ( Swanson-2004 ). For other components of the motor periaqueductal gray click below: Models Where It Appears > Functional CNS Model - Rat.