• Field H1, is the
thalamic fasciculus, a horizontal white matter tract composed of the
ansa lenticularis,
lenticular fasciculus, and
cerebellothalamic tracts between the subthalamus and the thalamus. These fibers are projections to the ventral anterior and ventral lateral thalamus from the
basal ganglia (
globus pallidus) and the
cerebellum. H1 is separated from H2 by the
zona incerta. • Field H2 (synonymous with
lenticular fasciculus) is also made up of projections from the
pallidum to the thalamus, but these course the subthalamic nucleus (dorsal). • Field H (sometimes called field H3) is a large zone of mixed
grey and white matter from the
pallidothalamic tracts of the lenticular fasciculus and the ansa lenticularis which combine in an area just in front of the
red nucleus. The grey matter from this field is said to form a
prerubral nucleus. ==Nuclei campi perizonalis==