| cerebellar peduncles | The cerebellum is attached to the brain stem by three pairs of tracts
called the _____________ which consist of numerous pathways
connecting the cerebellum with several other centers in the nervous
system. |
| “hemispheres," “vermis” | The body of the cerebellum is divided into two ___________
connected at the midline by the ________. |
| (i) The anterior lobe ,
(ii) The posterior lobe , and
(iii) the flocculonodular lobe. | Two of these fissures ; the primary
fissure and the posterolateral fissure,
are deeper than others , dividing the
cerebellum into 3 anatomical lobes : |
| The vermal zone, The intermediate (or paravermal) zone, The lateral zone | The cerebellum is functionally divided into longitudinal functional zones (3) |
| Vermal Zone | ___________ which occupies the vermis and is the most medial
part of the cerebellar cortex |
| The intermediate (or paravermal) zone | ______________ of the cerebellar
hemisphere, lying on each side of the vermis, occupying the medial
regions of the cerebellar hemispheres. |
| The Lateral Zone | ________________ of the cerebellar hemisphere, lying just lateral
to the intermediate zone. In humans this region occupies the greater
portion of the cerebellar hemisphere. |
| (i) The vestibulocerebellum.
(ii) The spinocerebellum.
(iii) The cerebrocerebellum. | The different regions of the cerebellum are functionally organized into three major divisions: |
| The Medial System and the Lateral System | An alternative classification of the descending motor tracts is based on the
sites of termination of these tracts in the spinal cord defines the two areas as: |
| composed of tracts which terminate primarily on the ventromedial neurons.
innervate the trunk (axial) muscles and the proximal (girdle) muscles of the limbs
more concerned with postural control | The Medial System: where does it terminate, what does it innervate and what does it mainly control? |
| composed of tracts which terminate primarily on the dorsolateral neurons (or their associated interneurons)
innervate the distal muscles of the limbs.
more concerned with controlling fine voluntary movements of the extremities. | The Medial System: where does it terminate, what does it innervate and what does it mainly control? |
| 1) the corticobulbospinal tract, (= Pyramidal tract, others are Extrapyramidal)
2) the vestibulospinal tracts,
3) the rubrospinal tract,
4) the reticulospinal tracts,and
5) the tectospinal tract. | There are five important sets of descending motor tracts, named according to
the origin of their cell bodies and their final destination: |
| The Vestibulocerebellum region of the cerebellum is composed of the | flocculonodular lobe |
| “vestibulocerebellum” gets it's name from.... | This brain area has a close functional relationship with the vestibular system; so it has been named the |
| What part of the cerebellum is this:
1) To control the activity of the motor pathways (the vestibulospinal and
reticulospinal tracts) concerned with regulation of the TON AND CONTRACTILITY OF THE ANTIGRAVITY MUSCLES in response to vestibular
sensory signals, and is therefore largely concerned with REGULATION OF EQUILIBRIUM.
2) To regulates movements of the eyeballs during head movements to maintain stable vision. | What does The Vestibulocerebellum do? |
| Most of the sensory information reaching these regions of the cerebellum
arrives from the spinal cord, thus they have been named the... | “spinocerebellum” |
| The “dorsal spinocerebellar tract” (DSCT)provide the cerebellum with sensory signals from muscle spindles, Golgi tendon organs, joint receptors, and cutaneous touch and pressure receptors. These signals inform the cerebellum about the present state of......? | These tracts provide the cerebellum with sensory signals from muscle
spindles, Golgi tendon organs, joint receptors, and cutaneous touch and
pressure receptors. These signals inform the cerebellum about the present
state of muscle contraction, position of the body, and movements of its
different parts. |
| What are two ways that the dorsal and ventral spinocerebellar tracts differ? | 1) The Ventral spinocerebellar tract only deals with the golgi tendon organs (not spindles)
2) The VSCT double crosses into the OPPOSITE SIDE OF THE BODY, in the spinal tract and in the cerebellum. |
| Together with internal models, _________ can serve to enable the brain to predict the effects of an action. | efference copies |
| An _______ _______ is used to generate the predicted sensory input which estimates the (somato)sensory consequences of a motor command (top row). | efference copy |
| ______, or motor, nerve fibres carry impulses away from the central nervous system | Efferent |
| _______, or sensory, fibres carry impulses toward the central nervous system | Afferent |
| Sensory information from the ______ ______ areas about the present
postural state of the body , while that from the ______ _____ informs the
cerebellum about the spatial position of the body in relation to the
surrounding environment | Somatic sensory, visual areas |
| What is the purpose of the "somatic system". | The ______ ______ is the part of the peripheral nervous system that is responsible for carrying motor and sensory information both to and from the central nervous system (CNS). |
| The _____is the principal region of the cerebellum concerned with
postural adjustment | vermis |
| _______ means lesions of CNS above the level of midbrain
(rubrospinal tract is intact) | Decorticate |
| __________ means lesions of CNS at a level between superior
colliculi and inferior colliculi (rubrospinal tract is not intact) | Decerebrate |
