Answer:
The NCF and PAG are brainstem nuclei involved in a network mediating anti- and pro-nociception, as largely shown from animal data (Fields and Basbaum, 1999 for a review, [Porreca et al., 2002] and [Gebhart, 2004]). Human imaging studies have shown that the PAG and NCF are activated during visceral and somatic pain (Dunckley et al., 2005) and that the NCF plays a key role in the development of experimental secondary hyperalgesia via possible facilitatory pro-nociceptive mechanisms (Zambreanu et al., 2005). The NCF and PAG have been shown to be important in brainstem modulation of pain in humans (Zambreanu et al., 2005), and connections to these nuclei provide an anatomical basis for results of recent studies involving pain control and perception ( [Lorenz et al., 2003], [Valet et al., 2004] and [Wager et al., 2004]). The NCF has recently been shown to be critical for the generation of secondary hyperalgesia in humans
Step-by-step explanation:
The NCF and PAG are brainstem nuclei involved in a network mediating anti- and pro-nociception, as largely shown from animal data (Fields and Basbaum, 1999 for a review, [Porreca et al., 2002] and [Gebhart, 2004]). Human imaging studies have shown that the PAG and NCF are activated during visceral and somatic pain (Dunckley et al., 2005) and that the NCF plays a key role in the development of experimental secondary hyperalgesia via possible facilitatory pro-nociceptive mechanisms (Zambreanu et al., 2005). The NCF and PAG have been shown to be important in brainstem modulation of pain in humans (Zambreanu et al., 2005), and connections to these nuclei provide an anatomical basis for results of recent studies involving pain control and perception ( [Lorenz et al., 2003], [Valet et al., 2004] and [Wager et al., 2004]). The NCF has recently been shown to be critical for the generation of secondary hyperalgesia in humans