11. Motor II - the CEREBELLUM, feedback and feedforward Flashcards
FUNCTION of the CEREBELLUM
CALIBRATES the PRECISION OF ACTION
- functions as an ERROR DETECTOR
had Feedback (if movement goes wrong to inhibit in the future) and Feedforward processing to IMPROVE ACCURATY of FUTURE MOVEMENTS
LACK of FUNCTION in the CEREBELLUM leads to..
CLUMSINESS
- ATAXIA (disordered movement)
or
- DYSMETRIA (badly measured movement)
what are the ASCENDING TRACTS
DORSAL COLUM
SPINOCEREBELLAR TRACT
SPINOTHALAMIC TRACT
(sensory)
what are the DESCENDING MOTOR TRACTS
*CORTICOSPINAL
(pyramidal corticospinal tract)
RETICULOSPINAL
VESTIBULOSPINAL
TECTOSPINAL
where is the CEREBELLUM LOCATED is an OUTGROWTH of what
the METENCEPHALON / PONS
the CORTICAL SURFACE of the Cerebellum is expanded by FOLDS called..
FOLIA
CEREBELLUM is estimated to have 10X MORE NEURONS than the Cerebral cortex.
largely due to its HIGH DENSITY of which cells
GRANULAR CELLS
CEREBELLUM is POSTERIOR to the PONS and which VENTRICLE
4TH VENTRICLE
which PEDUNCLE connects CEREBELLUM to the PONS and what feedback is it for
MIDDLE CEREBELLAR PEDUNCLE
aka BRACHIUM PONTIS
- for INPUT from CORTEX
where is the CEREBELLUM in relation to the MIDBRAIN and what are they CONNECTED by
INFERO-POSTERIOR to midbrain
- SUPERIOR CEREBELLAR PEDUNCLE
aka BRACHIUM CONJUNCTIVUM
SUPERIOR CEREBELLAR PEDUNCLE / BRACHIUM CONJUCTIVUM is for what between CEREBELLUM and MIDBRAIN
OUTPUT TO THALAMUS (& RED NUCLEUS)
- Decussates
where is the CEREBELLUM in relation to the MEDULLA and what are they CONNECTED by
SUPERO-POSTERIOR to medulla
- INFERIOR CEREBELLAR PEDUNCLE
aka RESTIFORM BODY
INFERIOR CEREBELLAR PEDUNCLE / RESTIFORM BODY is for what between CEREBELLUM and MEDULLA
INPUT FROM SPINAL CORD PROPRIOCEPTIVE CENTRES
- from DORSAL SPINOCEREBELLAR TRACT
which connection of the CEREBELLUM to the BRAIN STEM is for INPUT FROM DORSAL SPINOTHALAMIC TRACT from spinal cord PROPRIOCEPTIVE centre
INFERIOR PEDUNCLE from MEDULLA
which connection of the CEREBELLUM to the BRAIN STEM is for OUTPUT to the THALAMUS
SUPERIOR PEDUNCLE to the MIDBRAIN
MIDDLE CEREBRAL PEDUNCLE AKA
BRACHIUM PONTIS
what happens to the Feedback fibres between the CEREBELLUM and CEREBRAL CORTEX in Middle peduncle INPUT and Superior Peduncle OUTPUT
DECUSSATE
- upper part of the BRAIN controls OPPOSITE SIDE of the body
but CEREBELLUM helps coordination of movement on the SAME SIDE
which fibres have UNCROSSED INPUT to CEREBELLUM
DORSAL SPINOCEREBELLAR TRACTS from spinal cord via the INFERIOR PEDUNCLE (restiform body) from Medulla to Cerebellum
CEREBELLAR SYNDROMES are on the same or opposite side of the body?
IPSILESIONAL
- on the SAME SIDE of the body as the cerebellar LESION
what is the OLDEST part of the CEREBELLUM
VESTIBULOCEREBELLUM
aka FLOCCULONODULAR LOBE
aka ARCHICEREBELLUM
(dangling at bottom)
VESTIBULOCEREBELLUM aka FLOCCULONODULAR LOBE
aka ARCHICEREBELLUM is for what function
BALANCE & EYE MOVEMENT
- connects to vestibular system and vestibular Nuclei (in brainstem)
2nd oldest part of the Cerebellum that is found in the midline area is the SPINOCEREBELLUM aka PALEOCEREBELLUM. it connects to the SPINAL CORD via..
MEDIAL DESCENDING and LATERAL DESCENDING PATHWAYS
via the THALAMUS
(somatotopic, ipsilateral)
what is the LARGEST PART of the Cerebellum that connects to the FRONTAL LOBE anterior to the primary motor cortex (via THALAMUS)
CEREBO-CEREBELLUM aka NEOCEREBELLUM
CEREBELLAR FOLIA contains what in the CENTRE/CORE?
and what are the LAYERS going out
centre WHITE MATTER
-> GRANULE CELLS (GRANULAR LAYER)
-> PURKINJE CELLS and their DENDRITIC TREES (Purkinje Layer)
-> MOLECULAR LAYER (contains axons of the granule and purkinje cells)
STAIN used to see histology of Cerebellum
H&E
INPUT from which fibres form SYNAPSES with GRANULE CELLS in the Granular Layer
MOSSY FIBRES
(from brain stem nuclei and spinal cord)
INPUT from where forms SYNAPSES with PURKINJE CELLS
INFERIOR OLIVARY NUCLEUS
- comes from the OLIVE of the MEDULLA
connects to purkinje via CLIMBING FIBRES
PURKINJE CELLS (large) have a vast DENDRITIC TREE in the Molecular Layer.
how do the GRANULAR CELLS INTERACT with MANY purkinje cell DENDRITIC TREES
- Axons enter MOLECULAR LAYER
- form Long PARALLEL FIBRES which are perpendicular to the plane of the purkinje cells (dendritic trees)
GRANULE CELLS make how many CONNECTIONS with PURKINJE CELLS?
INFERIOR OLIVARY NUCLEUS (of Medulla) makes how many CONNECTIONS with PURKINJE CELLS
Granule cells: MANY
ION: ONLY ONE CONNECTION
GRANULE CELLS receive INPUT from…
MOSSY FIBRES
(non-ION inputs)
what is the OUTPUT from the PURKINJE CELL
INHIBITORY AXON sent to DEEP CEREBELLAR NUCLEUS to the BRAINSTEM
to descending motor tracts
which INPUT is an ERROR SIGNAL, sent when a MOVEMENT goes WRONG (signals a motor error)
INFERIOR OLIVARY NUCLEUS inputs
(from MEDULLA)
what is known as LONG-TERM DEPRESSION
the CO-FIRING of both GRANULE and ION fibres (parallel and climbing fibres)
SUPPRESSES THE PURKINJE CELL
Synapses weaken so in the future would need more excitation to stimulate
- involves Ca2+ Signalling
how does INFERIOR OLIVARY NUCLEUS connect to PURKINJE CELL
via..
CLIMBING FIBRE
1 connection
how does GRANULAR CELL connect to PURKINJE CELL
via..
PARALLEL FIBRE
what involves CA2+ SIGNALLING
LONG TERM DEPRESSION
where CO-FIRING SUPPRESSES PURKINJE CELL
INPUT of the INFERIOR OLVIARY NUCLEUS (MEDULLA)
ERROR SIGNAL
LIMB MOVEMENT accuracy by which tract
SPINOCEREBELLUM
EYE MOVEMENT and BALANCE accuracy by which tract
VESTIBULOCEREBLLUM
what are FOLIA
FOLDS on the CORTICAL SURFACE of CEREBELLUM
what is BRACHIUM CONJUNCTIVUM
SUPERIOR CEREBELLAR PEDUNCLE
that connects Cerebellum to the MIDBRAIN
(decussate)
INPUT from MEDULLA (SPINOCEREBELLAR TRACT) is decussated or uncrossed
UNCROSSED
