Kernicterus: In this section, there is deposition of yellow pigment in the subthalamus, thalamus, basal ganglia and hippocampus. This pigment deposition is associated with degeneration. Kernicterus is seen primarily in premature infants. At least three factors appear to be operating in the pathogenesis of this condition: hyperbilirubinemia, immature liver function and immature blood-brain barrier function. Other areas of the brain may be similarly affected.