transmit impulses to dorsal root
A delta-small diameter, thinly mylenated, fast pain characterized as sharp or prickling, localized, located on skin surface
C Fibers- slow pain- small diameter, unmylenated, less localized, do not trigger withdrawl reflex, associated with increased tissue damage
-Substaintia gelantinosa- lamina II of dorsal horn, pain modulation, gated mechanism.
-(anteriolateral) Contralateral tract- pain travels on opposite side of body.Pain crosses at midline at spinal cord level. Any damage to tract will result in contralateral loss of sensation.
-Dorsal-Column-medial lemniscus- conveys touch, pressure and corsses at midline of medulla. Contralateral sensation.