Contributions of the Cerebellum & Basal Nuclei in Motor Control (Part 2)

Balance between excitation & inhibition at the deep nuclear cells: - Activity by the _____ cortex or ______ ______ produces rapid movement. Initially, the deep nuclear cells are ______. ·- Then, inhibition from the ______ cells decreases the activity of the deep nuclear cells. - This ______ muscle movement & prevents "______."

- Activity by the motor cortex or brain stem produces rapid movement. Initially, the deep nuclear cells are stimulated. ·- Then, inhibition from the Purkinje cells decreases the activity of the deep nuclear cells. - This damps muscle movement & prevents "overshoot."

Turn on/off of cerebellar output signals: - At the onset of movement= cerebellum provides turn on signals for _______ muscles and turn off signals for ______ muscles. - At the end of movement= cerebellum provides turn off signals for _______ muscles and turn on signals for the ______. - This involves input to the cerebellum from the ______ (motor command) & ______ (actual movement).

- At the onset of movement= cerebellum provides turn on signals for agonist muscles and turn off signals for antagonist muscles. - At the end of movement= cerebellum provides turn off signals for agonist muscles and turn on signals for the antagonist. - This involves input to the cerebellum from the cortex (motor command) & periphery (actual movement).

Bottom line= Deep nuclear cells receive stimulation from climbing & mossy fibers and inhibition from Purjinke cells. They receive this input in a pattern that allows rapid initiation of movement (stimulation) but prevents overshoot (inhibition).

- Bottom line= Deep nuclear cells receive stimulation from climbing & mossy fibers and inhibition from Purjinke cells. They receive this input in a pattern that allows rapid initiation of movement (stimulation) but prevents overshoot (inhibition).

Function of the Cerebellum in Overall Motor Control Vestibulocerebellar functions: - Control of ______ during rapid movement. - Vestibulocerebellar functions controlled by the ______ lobes & nearby ______.

- Control of equilibrium during rapid movement. - Vestibulocerebellar functions controlled by the flocculonodular lobes & nearby vermis.

Function of the Cerebellum in Overall Motor Control Spinocerebellar Functions: - ______ ______ control. - Spinocerebellar function is controlled by the _______ & _______ zones of the posterior and anterior lobes.

- Distal limb control. - Spinocerebellar function is controlled by the vermis & intermediate zones of the posterior and anterior lobes.

Clinical Abnormalities of the Cerebellum Dysarthria - Failure of motor progression in ______ because the formation of words depends on rapid and orderly succession of individual muscle movements in the ______, ______, and ______ system. - Vocalizations are jumbles with some syllables loud and some syllables weak (some held for long intervals and some held for short intervals).

- Failure of motor progression in talking because the formation of words depends on rapid and orderly succession of individual muscle movements in the larynx, mouth, and respiratory system. - Vocalizations are jumbles with some syllables loud and some syllables weak (some held for long intervals and some held for short intervals).

Function of the Cerebellum in Overall Motor Control Cerebrocerebellar Functions: - Functions with ______ cortex to plan ______ voluntary limb movement. - Controlled by the ______ zones of both hemispheres.

- Functions with cerebral cortex to plan sequential voluntary limb movement. - Controlled by the lateral zones of both hemispheres.

Clinical Abnormalities of the Cerebellum Intention Tremor - Movements ______ when approaching intended mark. - Failure of cerebellar system to "_______" the motor movements.

- Movements oscillate when approaching intended mark. - Failure of cerebellar system to "damp" the motor movements.

Clinical Abnormalities of the Cerebellum Past Posturing - Specific form of ______. - Movement goes ______ its intended point. - Results when the ability of the cerebellum to ______ ______ movement fails.

- Specific form of dysmetria. - Movement goes beyond its intended point. - Results when the ability of the cerebellum to turn off movement fails.

Clinical Abnormalities of the Cerebellum Dysmetria: - Subconscious motor control system cannot ______ how ______ movements will go. - Movements ordinarily _______ their intended mark. The conscious portion of the brain ______. - Dysmetria results in ______, which is ______ movements.

- Subconscious motor control system cannot predict how far movements will go. - Movements ordinarily overshoot their intended mark. The conscious portion of the brain overcompensates. - Dysmetria results in ataxia, which is uncoordinated movements.

Function of the Cerebellum in Overall Motor Control Spinocerebellar Functions: - This coordinates ______/ ______ muscles. - Allows ______ movement of distal limbs. - ______ movement & prevents ______.

- This coordinates agonist/ antagonist muscles. - Allows smooth movement of distal limbs. - Damp movement & prevents overshoot.

Clinical Abnormalities of the Cerebellum Nystagmus - _______ of the eye muscle. - Common when _______ lobe damaged.

- Tremor of the eye muscle. - Common when flocculonodular lobe damaged.

Clinical Abnormalities of the Cerebellum Dysdiadochokinesia -Inability to perform ______ movements. - Motor control system fails to ______ where the different parts of the body will be at a given time. - The succeeding movement may begin much to early or much too late, so no orderly "______ of ______" can occur.

-Inability to perform rapid movements. - Motor control system fails to predict where the different parts of the body will be at a given time. - The succeeding movement may begin much to early or much too late, so no orderly "progression of movement" can occur

Function of the Cerebellum in Overall Motor Control Cerebrocerebellar Functions: Another important function of the lateral zones is to provide appropriate _______ of each succeeding movement.

Another important function of the lateral zones is to provide appropriate timing of each succeeding movement.

Balance between excitation & inhibition at the deep nuclear cells: At rest, the amount of ______ exceeds the amount of ______. This generates a _______ and ______ level of continuous output from the ______ _____ cells.

At rest, the amount of excitation exceeds the amount of inhibition. This generates a constant and moderate level of continuous output from the deep nuclear cells.

There are other inhibitory cells: ______ cells & ______ cells in the molecular layer. They produce lateral inhibition of ______ cells, which "______" the movement.

Basket cells & stellate cells in the molecular layer. They produce lateral inhibition of Purkinje cells, which "sharpens" the movement.

Bottom Line= The deep nuclear cells provide output from the cerebellum. They get excited by the climbing fibers coming from the brain & periphery and the mossy fibers coming from the brain stem, cortex, or cord. They are inhibited by the Purkinje cells.

Bottom Line= The deep nuclear cells provide output from the cerebellum. They get excited by the climbing fibers coming from the brain & periphery and the mossy fibers coming from the brain stem, cortex, or cord. They are inhibited by the Purkinje cells.

Function of the Cerebellum in Overall Motor Control Vestibulocerebellar functions: Can ______ the body position ahead of feedback from the _______ movement. Gives feedback to the ______ to make ______ corrections ahead of actual feedback from periphery.

Can project the body position ahead of feedback from the actual movement. Gives feedback to the periphery to make anticipatory corrections ahead of actual feedback from periphery.

Purkinje Cells "Learn" to Correct Motor Errors: Initial performance of motor activity (doing it for the first time) you have ______ turn on/off. This causes incorrect ______. If you repeat the activity several time, you get more ______ turn on/off and this causes the correct ______.

Initial performance of motor activity (doing it for the first time) you have imprecise turn on/off. This causes incorrect movement. If you repeat the activity several time, you get more precise turn on/off and this causes the correct movements.

Neuronal Circuit of the Functional Unit: Output from the functional unit comes from the ______ ______ ______. · These deep nuclear cells receive excitatory input from the ______ & ______. · They receive inhibitory input from the ______ cells.

Output from the functional unit comes from the deep nuclear cell. · These deep nuclear cells receive excitatory input from the brain & periphery. · They receive inhibitory input from the Purkinje cells.

Function of the Cerebellum in Overall Motor Control Cerebrocerebellar Functions: Planning of sequential limb movements requires the lateral zones to communicate with both the ______ areas and ______ areas. · The plan beings in the ______ & ______ cortex and is transmitted to the ______ zones of the cerebellum. · The lateral zones send ______ signals which allow for the transition of sequential movements.

Planning of sequential limb movements requires the lateral zones to communicate with both the premotor areas and somatosensory areas. · The plan beings in the sensory & premotor cortex and is transmitted to the lateral zones of the cerebellum. · The lateral zones send return signals which allow for the transition of sequential movements.

Function of the Cerebellum in Overall Motor Control Cerebrocerebellar Functions: Rates of progression of both ______ and ______ input can also be predicted by the cerebellum.

Rates of progression of both auditory and visual input can also be predicted by the cerebellum.

Neuronal Circuit of the Functional Unit: The climbing fibers originate in the ______. They excite both the ______ cells & _____ _____ cells. · 1 AP in a climbing fiber cell causes a _______ spike in the ______. Complex spike= a strong spike followed by a trail of weakened secondary spikes.

The climbing fibers originate in the medulla. They excite both the Purkinje cells & deep nuclear cells. · 1 AP in a climbing fiber cell causes a complex spike in the Purkinje. Complex spike= a strong spike followed by a trail of weakened secondary spikes.

The ______ cells and the ______ ______ cells are the functional unit of the cerebral cortex.

The Purkinje cells and the deep nuclear cells are the functional unit of the cerebral cortex.

Purkinje Cells "Learn" to Correct Motor Errors: The ______ fibers bring input from the _______ about how precise the movement was. This alters the sensitivity of _______ cells and the Purkinje cells "______." The activity becomes more and more ______.

The climbing fibers bring input from the periphery about how precise the movement was. This alters the sensitivity of Purkinje cells and the Purkinje cells "learn." The activity becomes more and more precise.

Balance between excitation & inhibition at the deep nuclear cells: The deep nuclear cells receive excitatory input from the ______ & ______ fibers. The deep nuclear cells receive inhibitory input from the ______ cells.

The deep nuclear cells receive excitatory input from the climbing & mossy fibers. The deep nuclear cells receive inhibitory input from the Purkinje cells.

Function of the Cerebellum in Overall Motor Control Vestibulocerebellar functions: The flocculonodular lobes & nearby vermis are going to work with the ______ _____ to control equilibrium during rapid movement.

The flocculonodular lobes & nearby vermis are going to work with the vestibular apparatus to control equilibrium during rapid movement.

Function of the Cerebellum in Overall Motor Control Spinocerebellar Functions: The intermediate zone compares the ______ vs. _____ movement & sends corrective output: · Back to the ______ cortex via the ______. · To the ______ ______ to descend the ______ tract and control ______ ______ muscles.

The intermediate zone compares the actual vs. intended movement & sends corrective output: · Back to the motor cortex via the thalamus. · To the red nucleus to descend the rubrospinal tract and control distal limb muscles.

Function of the Cerebellum in Overall Motor Control Spinocerebellar Functions: The intermediate zone gets input from: · _______ cortex & ______ ______ about ______ movements. · They also get feedback from the ______ about ______ movements via the spinocerebellar tract.

The intermediate zone gets input from: · Motor cortex & red nucleus about intended movements. · They also get feedback from the periphery about actual movements via the spinocerebellar tract.

Neuronal Circuit of the Functional Unit: The mossy fibers originate in the ______, ______ ______, and the ______. · These fibers excite ______ ______ cells & ______ cells. · The granule cells send ______ nerve fibers to ______. These parallel nerve fibers synapse with each Purkinje cell. · The Purkinje cell AP is called a _______ spike (weaker, shorter duration).

The mossy fibers originate in the cortex, brain stem, and the cord. · These fibers excite deep nuclear cells & granule cells. · The granule cells send parallel nerve fibers to Purkinje. These parallel nerve fibers synapse with each Purkinje cell. · The Purkinje cell AP is called a simple spike (weaker, shorter duration).

There are 3 layers of the cerebral cortex—the _______ layer, the ______ cell layer, and the ______ layer. Beneath these cortical layers are the ______ ______ ______.

There are 3 layers of the cerebral cortex—the molecular layer, the Purkinje cell layer, and the granular layer. Beneath these cortical layers are the deep cerebellar nuclei.