Sensorimotor functions of the cerebellum

EXCI-355 Neural Control of Human

Movement

Producing adapted movements

Plan

Cerebellar structuresConnectivityMovement implicationsPathology

Textbooks

Neuroscience, Purves et al.

Principles of Neural Science, Kandel et al.

Functions of the cerebellum

Motor correction: adjusting movement on the fly based on sensory and proprioceptive input

Motor learning: Improving performance of motor sequences with repetition

Balance, coordinating muscle systems across the body

Figure 19.1 Overall organization and subdivisions of the cerebellum (Part 1)

Know your cerebellum!

Figure 19.1 Ventral organization and subdivisions of the cerebellum (Part 2)

Figure 19.1 Overall organization and subdivisions of the cerebellum (Part 3)

Figure 19.2 Brainstem and diencephalon components related to the cerebellum

Pontine nuclei – cortical inputInferior olive – movement error/correctionCuneate & Clarke – proprioceptive input

midbrain

pons

medulla

Figure 19.3 Functional organization of the inputs to the cerebellum (Part 1)

Ascending vs. descending connectivity

Cerebellum

Cortex

Brainstem

Descendinginput

Descendinginput

Ascending input

Ascending input

DescendingprojectionsDescendingprojections

Ascending projectionsAscending projections

Summary of inputs to the cerebellum

Descending (from cortex) Motor cortex: Movement commands Premotor cortex: Planning/selecting movement Relayed via pontine and red nuclei

Ascending input (sensory information) Proprioceptive information Vestibular information

Figure 19.3 Functional organization of the inputs to the cerebellum (Part 2)

Regions of the cerebral cortex that project to the cerebellum

Cortical inputs: premotor and motor areas in the frontal cortex, and sensory areas in the parietal cortex

F P

OT

Figure 19.1 Functional organization of cerebellar hemispheres

Cerebrocerebellum: Motor planning and coordination

Spinocerebellum: Control of ongoing body and limb movements

Vestibulocerebellum: Posture, balance, eye movements

Figure 19.4 Somatotopic maps of the body surface in the cerebellum

Sensory inputs remain topographically mapped

Nearby cerebellar areas control adjacent body parts

Figure 19.5 Functional organization of cerebellar outputs

Figure 19.6 Functional organization of the major ascending outputs from the cerebellum (Part 1)

Outputs of deep cerebellar nuclei: Exit the cerebellum

through the superior cerebellar peduncle

Project direct to subcortical targets

Through the thalamus to motor cortex

Figure 19.6 Functional organization of the major ascending outputs from the cerebellum (Part 2)

Figure 19.8 Functional organization of the major descending outputs from the cerebellum

Summary of efferent projections from the cerebellum

Ascending: Back to motor and premotor cortex

Descending: Superior colliculus: eye movements Reticular formation: planning/correcting

movement Vestibular nuclei: balance

Activity

The cerebellum cares about the opposite side of the body _____

The cerebellum gets information from the spinal cord _____

The cerebellum gets information from the cerebral cortex _____

The cerebellum is organized of a cortex part and a nuclear part _____

Activity

The cerebellum cares about the opposite side of the body __F___

The cerebellum gets information from the spinal cord __T___

The cerebellum gets information from the cerebral cortex __T___

The cerebellum is organized of a cortex part and a nuclear part __T___

Figure 19.14 The pathology of neurological diseases provides insights into the function of the cerebellum

What part of cerebellum is damaged?

Figure 19.1 Overall organization and subdivisions of the cerebellum (Part 1)

How might this damage give rise to the deficit seen?

http://www.youtube.com/watch?v=0jYaeRzYF94

Figure 19.4 Somatotopic maps of the body surface in the cerebellum

Sensory inputs remain topographically mapped

Nearby cerebellar areas control adjacent body parts

Which part of cerebellum do you think is affected?

http://www.youtube.com/watch?v=5eBwn22Bnio

Which hemisphere is lesioned?

Conclusions

The cerebellum helps in motor coordination by parallel computations

Is involved in motor planning and execution Damage to the cerebellum:

Causes ipsilateral deficits Interferes with smooth, coordinate movement