<prompt> Stimulation of which brain area can modulate the sensation of pain?Superior olivary complexLocus ceruleusPeriaquaductal grayAmygdala  <response>: Endogenous analgesic system periaqueductal gray PAG-projects to nucleus raphé magnus and rostral ventromedial medulla project to the dorsal horn of the spinal cord- release serotonin and norepinephrine Locus coerulus-Nor epinephrine Stress induced analgesia: release of endogenous cannabinoids such as 2-arachidonoylglycerol 2AG and anandamide acts on CB1Euphoria and CB 2 Painreceptors 