Motor Control and the Basal Ganglia Flashcards
What is the main function of the cerebellum?
Acts as a functional comparator; It receives information from the sensory system located in the muscles, ‘bows’ to the vestibular system, and the visual system and compares the information with
How is the Cerebellum connected to the the rest of the brain?
Connected to the posterior aspect of the brainstem, by the superior middle and inferior cerebella peduncle.
(A peduncle is a bundle of nerve fibres).
The superior peduncle connects the cerebellum to the ____?
The Superior peduncle connects the cerebellum to the midbrain.
The middle peduncle connects the cerebellum to the ____?
The middle peduncle connects the cerebellum to the pumps.
The inferior peduncle connects the cerebellum to the ____?
The inferior peduncle connects the cerebellum to the medulla.
How many hemispheres does the cerebellum have?
2
What connects the 2 hemispheres of the cerebellum?
A narrow median vermis
What is the vermis?
Responsible for the control of the muscles on the long axis of the body.
Which parts cerebral hemispheres control which limbs/movements?
- Intermediate zone
- Most lateral zones
They control the distal limbs, in what’s called the intermediate zone and the sequential movement in the most lateral zones.
What main lobes make up the cerebellum?
- Anterior
- Posterior
- Flocculo-nodular lobe
What divides the anterior and posterior lobes of the cerebellum?
Primary fissure.
What divides the Posterior and Flocculo-nodular lobe?
Overall nodal fissure.
What divides/separates the Superior and inferior surfaces?
Deep horizontal fissures
What is the Cerebrocerebellum?
(aka “Neocerebellum”)
What is its function, where does it connect?
And where does it Communicate with in the brain?
Its one of the 3 different regions of the cerebellum, they’re divided according to evolution and their connections.
- “Neocerebellum” as its the most recent in terms of evolution.
- Involved in motor planning and cognitive functions.
- And “connects” to the thalamus (ventrolateral nucleus)
- The most / highest specialised part of the cerebellum.
What is the Spinocerebellum?
What is its function, where does it connect?
And where does it Communicate with in the brain?
Its one of the 3 different regions of the cerebellum, they’re divided according to evolution and their connections.
- Spinocerebellum aka “paleocerebellum”
- Its function is related to posture.
- It connects to the red nucleus in the midbrain.
What is the Vestibulocerebellum?
What is its function, where does it connect?
And where does it Communicate with in the brain?
Its one of the 3 different regions of the cerebellum, they’re divided according to evolution and their connections.
- Vestibulocerebellum aka “Archicerebellum”.
- Function relates to the control of balance.
- Connects to the vestibular nuclei in the brain.
What is the cerebral cortex?
A covering of grey matter that’s more superficial than the white matter, the grey matter is arranged into 3 layers, so the cortex is also divided into 3 layers.
What are the 3 layers of the cerebral cortex?
And which cells do they each contain?
- Molecular layer; Contains stellate and basket cells
- Purkinje cell layer; Contains the cell body of the Purkinje cells
- Granule cell layer; contains Golgi cells
What are the Climbing and Mossy fibres in the white matter beneath the cerebral cortex?
They are the 2 main lines of input to the cortex, and they are excitatory to the Purkinje cells.
What is the significance of card no.19?
about the mossy and climbing fibres and how they interact with the cerebral cortex
They have an input not only to the cells in the cortex but also to the central nuclei. There is a delay where that info is elaborated to the purine cells and then its related to the nuclei.
The significance of this is that the mossy & climbing fibres have a excitatory activity on the deep cerebellar nuclei, and the same info is processed by the purkinje cells that have an inhibitory effect on the nuclei.
Does a lesion on one hemisphere of the cerebellum give rise to symptoms on the same or opposite side of the body?
Same side, they are ipsilateral as the fibres from the cerebellum do not cross over.
Where does the efferent information from the nuclei in the cerebral cortex go?
Go to the brain and spinal cord.
What nuclei are present on the cerebellum?
Laterally –> medially
- Dentate nucleus
- Emboliform nucleus
- Globose nucleus
- Fastigial nucleus
What is the Thalamus?
The thalamus is a nucleus (of cell bodies, grey matter) in the brain and is medial to the internal capsules.
Related to the control of movement as it relays information to the cortex and to other structures, and receives info from these structures as well as being involved in ascending and descending pathways.
