Neuro Ii - Unit I - Motor Systems Lec 2

Front 1

Neuro II - Unit I - Motor Systems Lec 2

Back 1

Neuro II - Unit I - Motor Systems Lec 2

Front 2

Look @ pic 1, just to get an overall idea

Back 2

Look @ pic 1, just to get an overall idea

Front 3

Indirect CTL of LMNs

---Pic 2---

1. What are 2 subcortical structures that influence activity of the motor cortex and therefore LMNs & Mvt?

2. But, Cerebellum and Basal nuclei (ganglia) do not project directly to cortex, they first project somewhere else, where is that place?

3. Overall path?

Back 3

1. Cerebellum & Basal Nuclei (AKA: Basal Ganglia = Caudate, Putamen, Globus Pallidus, etc...)

2. Ventral anterior & ventral lateral nuclei of thalamus

3. Cerebellum and basal nuclei -->
ventral ant & ventral lat thalamic nuclei -->
motor cortex

Front 4

Indirect CTL of LMNs - Cerebellar Anatomy

---Pic 3---
1. Cerebellum interconnected to brainstem via what 3 large bundle of axons?

2. Name 3 parts of cerebellum?

Back 4

1. Superior, Middle, Inferior Cerebellar Peduncles

2. Cerebellar Cortex, White matter, deep cerebellar nuclei in white matter

Front 5

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Cortex Structural Anatomy

---Pic 3---
1. Cerebellar cortex folded into ridges called what?

2. What fissure marks posterior border of anterior lobe?

3. Posterior lobe extends b/t what 2 fissures?

4. Floculonodular lobe lies posterior to what fissure?

Back 5

1. Folia

2. Primary fissure

3. Anterior Fissure, Posterolateral Fissure

4. Posterolateral fissure

Front 6

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Cortex Functional Anatomy

1. 3 Functional Areas of Cerebellum?

2. Each Functional area of cerebellum assoc w/ different nuclei - name them!

Back 6

1. Vermis and Cortex Lateral to it (Paravermis / Intermed Cortex) (Spinocerebellum / Paleocerebellum)
Lateral Hemispheres (Lat to Vermis) (Neocerebellum) (Cerebrocerebellum)
Floculonodular Lobe

2. Vermis and Cortex lateral to it (Paravermis / Intermed Cortex / Spinocerebellum) (Paleocerebellum) = Globose & Emboliform Nuclei
Lateral Hemispheres (Neocerebellum) (Cerebrocerebellum) = Dentate Nucleus
FN Lobe = Fastigial Nucleus

Front 7

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Vestibulocerebellum

1. Vestibulocerebellum (Archicerebellum) is the name given to what 2 components of the cerebellum?

2. 2 Fnctns of Vestibulocerebellum (Archicerebellum)?

3. Path for Vestibucerebellum (Archicerebellum)?

Back 7

1. Flocculonodular lobe, Fastigial nucleus

2. Adjustment of posture and gait,
by CTL-ing neck, trunk, prox limb muscles,
in response to vestibular inputs

3. Sensory from Vestib Ganglion & BS Vestib Nuclei -->
Purkinje Cells of FN Lobe Cortex -->
Fastigial Nucleus -->
BS Vestib Nuclei & BS Retic Formation-->
LMNs in Neck, Trunk, Prox Limb

Front 8

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Vermis and Cortex Lateral to it (Paravermis / Intermed Cortex) (Spinocerebellum / Paleocerebellum)

1. 2 Functions of Spinocerebellum?

2. Path?

Back 8

1. Adjustment of posture and gait by CTL-ing neck, trunk, prox limb muscles in response to proprioceptive input

2. Sensory from Ant & Post Spinocerebellar (for body) & Cuneocerebellar (for limbs) Tracts -->
Spinocerebellum

Vermis --> Fastigial Nucleus (like Vestibulocerebellar Tract)

Intermed Cortex -->
Globose & Emboliform Nuclei -->
Cross Over to ContraLat Red Nucleus & Ventral Lat Nucleus of Thal

Red Nucleus -->
Cross Over to Contralat Rubrospional Tract -->
LMNs that CTL of upper Limbs

Ventral Lat Nuc of Thal -->
Motor Cortex -->
UMNs -->
Corticospinal Tract -->
LMNs that CTL Trunk & Limbs

Front 9

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Neocerebellum (Cerebrocerebellum)

1. Neocerebellum / Cerebrocerebellum are alternate terms for what?

2. Cerebrocerebellum modulates contraction of what muscle groups?

3. Cerebrocerebellum impt in learned motor behaviors, esp what type?

4. Neocerebellum / Cerebrocerebellum provides neural substrate for what?

5. Path?

Back 9

1. Lat hemisphere & dentate nucleus

2. Agonist - Antagonist Muscle Groups

3. small, individual mvtts (instrument) and limb balance (throwing ball)

4. Complex mvts of limbs and face

5. Cerebral Cortex -->
Pons -->
Cross Over via Middle Cerebellar Peduncle to Neocerebellum (Cerebrocerebellum)

Neocerebellum (Cerebrocerebellum) Purkinje Cells -->
Dentate Nucleus -->
Superior Cerebellar Peduncle -->
Cross Over Red Nucleus & Motor Thalamic Nuclei

Red Nucleus cross over -->
Rubrospinal Tract -->
LMNs that CTL Upper Limb

Motor Thalamic Nuclei -->
Frontal, Premotor, Supplemental Motor Cortex -->
Planning & Executing Mvt

Front 10

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Other Misc BS Structures that infl. cerebellum

1. This structure receives input from cerebral cortex and sends projections to all parts of cerebellum?

2. This structure has many inputs to cerebellar nuclei and mossy fibers in the cerebellar cortex?
A. Fnctn?

Back 10

1. Inferior olivary complex

2. Reticular formation
A. Modeulate overall activity in Cerebellum

Front 11

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Cerebellar Pathologies

1. Lesions of Floculonodular Lobe & Vermis demonstraet what 7 sympsoms?

Back 11

1. Truncal Ataxis
Gait Ataxia
Widebased, Swaying stance
Inability to walk heel-to-toe
Inability to stand heel-to-toe
Nystagmus
Dizziness

Front 12

Indirect CTL of LMNs - Cerebellar Anatomy - Cerebellar Pathways for Indirect CTL of LMNs - Cerebellar Pathologies

1. Lesions of Lat Hemisphere & Dentate Nucleus cause 6 symptoms that, when grouped, are called what?

2. List the 6 Symptoms and what they are?

3. Are these signs ipsilat or contralat to lesions?

Back 12

1. Dyssynergia

2. Decomposition of Mvt: No smooth transitions in muscle contractions in mvt towards goal

Dysmetria: Past Pointing

Intention Tremor: Tremor when attempting to touch something, none @ rest

Dysdiadochokinesis: Can't perform Rapid, Repetitive or Alternating Mvts

Dysarthritic Speech: slow, garbled, weak speech

Nystagmus / probs in binocular targeting of eyes

3. Ipsilat

Front 13

Indirect CTL of LMNs - Basal Nuclei Anatomy

---Pic 4---

1. These 2 basal nuclei are together called the neostriatum?

2. This basal nucleus is AKA Paleostriatum?
A. 2 parts?

3. These 2 basal nuclei are AKA Lenticular Nucleus?

4. This nucleus is where caudate nucleus and and putamen merge?

5. What 3 nuclei form a zone inferior to the lenticular nuclei and lat to hypothal?

Back 13

1. Caudate & Putamen

2. Globus Pallidus
A. Intermal (Medial) & External (Lateral) Segments

3. Putamen & Globus Pallidus

4. Nucleus Accumbens

5. Basal Nucleus of Meynert, Substantia Innominata, Olfactory Tubercle

Front 14

Indirect CTL of LMNs - Basal Nuclei Anatomy

1. Neostriatum (caudate and putamen) composed of what type of neurons?
A. These Neurons will be clustered into 1 of what 2 domains?

Back 14

1. Medium, Spiny Neurons
A. Matrix, Striosome

Front 15

Indirect CTL of LMNs - Basal Nuclei Connections to Thalamic & Midbrain Nuclei

1. This nucleus is connected to the basal nuclei, and is impt for limb mvts?

2. These 2 parts of Midbrain are a source of impt input to basal nuclei?
A. Substantia Nigra divided into what 2 parts?
B. Where are these located?

Back 15

1. Subthalamic Nucleus

2. Substantia Nigra & Ventral Tegmental Area
A. Reticular Component (SNr) & Compact Zone (SNc)
B. Reticular Component (SNr) = Adj to Crus Cerebri
Compact Zone (SNc) = Dorsal ot Reticular part

Front 16

Indirect CTL of LMNs - Basal Nuclei Neurochemistry

1. Major neurotransmitter of neostriatum (caudate & putamen?

2. What types of neurons are used by the neostriatum (caudate & putamen) efferently?
A. Release what inhibitory NT?
B. GABA is also the inhib NT throughout what nuclei?

3. Most common excitatory NT of Basal Nuclei?

4. What NT is used by the pars compacta of the Substantia Nigra?

Back 16

1. ACh

2. Medium Spiny Neurons
A. GABA
B. Basal Nuclei

3. Glutamate

4. Dopamine

Front 17

Indirect CTL of LMNs - Basal Nuclei Paths Overview

1. Basal Nuclei usually receive info from ____ & send info to ____..

2. Overall fnctn?

3. List 5 pathways and their specific jobs?

Back 17

1. Many Cortical Areas, Frontal Cortex

2. Determine behavior necessary to achieve a particular goal of mvt

3. Motor Loop: Volitional Mvt
Oculomotor Loop: CTLs Coordinated mvt of eyes
Dorsolat & prefrontal loop: Integrate mvt based on higher cognitive aeras
Limbic Loop: Places behavior into appropriate emotion / social context

Front 18

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Paths - Motor Loop

1. Remember, the Motor Loop is responsible for what type of mvt?
A. Unique mech of CTL'ing volitional mvt?

2. 2 Parts of Motor Loop?

3. Direct Loop Path?

4. Indirect Loop Path?

Back 18

1. Volitional
A. Disinhibiting motor thalamic nuclei

2. Direct & Indirect Loops

3. Neocortex -->
Putamen of Neostriatum -->
Inhib of Basal Nuclei Internal Globus Pallidus (GPi) &
Substantia Nigra Pars Reticulata (SNr)
-->
No more Inhibition of Motor Thalamus (Vent Ant, Vent Lat, Intralam Nuc) -->
Stim of Motor Cortex -->
Volitional Mvt

4. Neocortex -->
Putamen of Neostriatum -->
Inhib of GPe -->
Inhib of Subthalamic Nuc -->
Inhib of Basal Nuclei Internal Globus Pallidus (GPi) &
Substantia Nigra Pars Reticulata (SNr) -->
Inhibition of Motor Thalamus (Vent Ant, Vent Lat, Intralam) -->
NO MORE STIM of Motor Cortex -->
NO MORE Volitional Mvt

Front 19

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Paths - Motor Loop

1. Note, Indirect loop is longer than direct loop, what is the consequence of this?

2. Substantia Nigra Pars Compacta (SNc) sends dopaminergic input to Putamen of both direct and indirect pathways, and usually increases or decreases Volitional Mvt?
A. Effect on Putamen in Direct Loop?
B. Effect on Putamen in Indirect Loop?

Back 19

1. Motor Cortex for volitional mvt receives an rapid "on-off" input from motor thalamus

2. Increases
A. Excitatory
B. Inhibitory

Front 20

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Paths - Motor Loop

1. Note, Indirect loop is longer than direct loop, what is the consequence of this?

2. Substantia Nigra Pars Compacta (SNc) sends dopaminergic input to Putamen of both direct and indirect pathways, and usually increases or decreases Volitional Mvt?
A. Effect on Putamen in Direct Loop?
B. Effect on Putamen in Indirect Loop?

Back 20

1. Motor Cortex for volitional mvt receives an rapid "on-off" input from motor thalamus

2. Increases
A. Excitatory
B. Inhibitory

Front 21

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. Dysfunction of basal nuclei produce abnormal movements, why?

2. Dysfunction of basal nuclei causes what 2 types of abnormal mvts?

3. 2 Diff types Hypokinetic Mvts?
A. What is Bradykinesia? 2 Causes?
B. What is Akinesia?

Back 21

1. Imbalance b/t direct & indirect paths of motor loop

2. Hypokinetic & Hyperkinetic

3. Akinesia & Bradykinesia
A. Slow mvt; Dec motor cortex output, simultaneous contraction of agonists and antagonists
B. Complete loss of volitional mvt

Front 22

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. 3 Diff types Hyperkinetic Mvts?
A. Etiology of Hyperkinetic Mvts?

2. Ballismus
A. What?
B. Etiology?

Back 22

1. Ballismus, Choreiform mvts, Athetoid mvts
A. Probs w/ indirect pathway -->
Inc Direct Pathway -->
Excessive volitional Mvt

2.
A. Uncontrolled flinging of upper & lower limbs
B. Destruction of ContralLat Subthal Nucleus -->
Inhib of GPi -->
No inhib from GPi to Motor Thalamus -->
Increased Output to Motor Cortex -->
Excessive Volitional Mvts

Front 23

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. Choreiform Mvts
A. What?
B. Etiology?

2. Athetosis
A. What?
B. Etiology

Back 23

1. Choreiform Mvts
A. Jerking, "Dance-like" limb mvts; Facial / Oral Ticks
B. Loss of Neostriatum --> Dec Indirect Path and Inc Direct Path

2.
A. Slow, writhing mvts of limbs, trunk, neck, face
B. Loss of Neostriatum --> Dec Indirect Path and Inc Direct Path

Front 24

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. Parkinson's
A. Etiology?
B. 9 Motor Signs?

2. 3 Non-Motor Signs?

3. 2 Tx Options?

Back 24

1. Parkinson's
A. Loss of Dopaminergic Input to Putamen -->
Dec Direct Path & Inc Indirect Path
B. Akinesia, Bradykinesia, Tremor @ Rest, "Lead-Pipe" Rigidity, Resistance to passive mvt in flexion / Ext, Rache-like / Cogwheel rigidity, Dec eye mvts, lack of facial expression, loss of postural control

2. Dec cognitive, intellectual, emotional capacity

3. Pharmacological restoration of dopaminergic activity
Surgical destruction of basal nuclei

Front 25

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. Huntington Chorea
A. Etiology?
B. Motor Sign?
C. 2 Non-Motor Signs?

Back 25

1. Huntington Chorea
A. Autosomal Dom degeneration of cholinergic neurons of neostriatum Indirect Pathway
B. Choreiform Mvts --> can't perform volitional mvts
C. Dec cognitive and emotional capacity

Front 26

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies
1. Tardive Dyskinesia result of what?

Back 26

1. Pharmacologic intervention in dopaminergic pathway of brain

Front 27

Indirect CTL of LMNs - Basal Nuclei - Basal Nuclei Pathologies

1. Wilson's hepatolenticular disease
A. Etiology?

2. Sydenham chorea
A. Etiology?

Back 27

1. Wilson's
A. Autusomal recessive dysfunction in copper metabolism -->
Striatum lesions -->
Motor Deficits

2. Sydenham chorea
A. Rheumatic fever -->
Motor disturbances in kids