Cerebellar shomunculus

Homunculus, the cerebellum

Cerebellar homunculus.

The body has a double somatotop representation in the spinocerebellar portion of the cerebellum; 1/ in the anterior lobe and 2/ in the posterior lobe.

1/ The homunculus map seen here shows a largely reasonably cohesive whole body with the head facing backwards and the feet forward.

2/ Here the body is depicted as two separated halves with the head directed forward and the feet backwards; Thus, conversely, the map in the lobus anterior.

In both cases, the trunk, shoulders and hips, as well as the head are represented by bark areas in the vermis. More distal parts of the extremities have their representations in the intermediate hemisphere part.

The somatotopic representation with respect to sensory inflow and motor influence is considered to broadly coincide .

Note that in both representations, the right half of the body is "depicted" in the right hemisphere half and the left in the left half; Thus, reverse obsolescences compared to the cerebrum where the homunculus map in one cerebrum hemisphere represents the opposite half of the body.

It should also be noted that the somatotopic representation is far from accurate. One speaks of a " fractured somatotopia" in the cerebellar cortex! An example of this is that within one and the same limited section of bark, information from the jaw, and from different parts of the anterior and posterior limbs, is mixed with each other.