Zones
Zones
The DSCT and CCT
pathways convey unconscious proprioception regarding the
ipsilateral side of the body. The mesencephalic nucleus of V
(trigeminal) conveys such information from the face, and
these trigeminocerebellar axons form a minuscule part
of the middle cerebellar peduncle.
The most important thing that I want you to
know is that the DSCT and CCT project to the medial
and intermediate zones. These projections are
topographically organized. For instance, there is a
representation of the ipsilateral side of the body and head
in the anterior lobe (rostral to the primary fissure). You
can see that the trunk and neck are represented in the
medial zone. This input would be conveyed by both CCT
and DSCT fibers. The arm and leg are represented in the
intermediate zone via projections from both DSCT and
CCT fibers. There is a second, larger representation of the
ipsilateral side of the body and head in the posterior lobe,
and the topographic organization of DSCT and CCT inputs are
similar to the anterior lobe. There is a mirror image
representation of the body map in the anterior and posterior
lobes, such that the head representations lie next to each
other.