11/25/2011. TÁMOP – 4.1.2-08/2/A/KMR-2009-0006 1 Development of Complex Curricula for Molecular Bionics and Infobionics Programs within a consortial* framework**
Consortium leader
PETER PAZMANY CATHOLIC UNIVERSITY
Consortium members
SEMMELWEIS UNIVERSITY, DIALOG CAMPUS PUBLISHER
The Project has been realised with the support of the European Union and has been co-financed by the European Social Fund ***
**Molekuláris bionika és Infobionika Szakok tananyagának komplex fejlesztése konzorciumi keretben
***A projekt az Európai Unió támogatásával, az Európai Szociális Alap társfinanszírozásával valósul meg.
Faculty of Information Technology
BASICS OF NEUROBIOLOGY
MOTOR SYSTEMS
www.itk.ppke.hu
Neurobiológia alapjai
(Motoros rendszerek)
ZSOLT LIPOSITS
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CHARACTERISTICS OF THE MOTOR SYSTEMS
EXTRAFUSAL STRIATED MUSCLE FIBERS AND ALPHA MOTONEURONS THAT INNER- VATE THEM FORM THE MOTOR UNIT. THE SOMATO-MOTONEURONS ARE DISTRIBUTED IN THE BRAIN STEM AND THE SPINAL CORD. COLLECTIVELY, THEY ARE CALLED AS LOWER MOTONEURONS
LOWER MOTONEURONS ARE CONTROLLED BY UPPER MOTONEURONS. THE TERM REFERS TO DESCENDING PATHWAYS (CORTICOSPINAL, RUBROSPINAL, TECTOSPINAL, VESTIBULOSPINAL, RETICULOSPINAL TRACTS) THAT REGULATE THE LOWER MOTO- NEURONS EITHER BY A DIRECT OR AN INTERNEURON-MEDIATED MANNER
THE MAIN MOTOR SYSTEMS INCLUDE THE MOTOR CORTEX, THE CEREBELLAR
MACHINERY AND THE BASAL GANGLIA. THE LATTER TWO SYSTEMS ARE CHANNELED TO THE FRONTAL MOTOR CORTEX VIA THE VENTRAL LATERAL NUCLEUS OF THE
THALAMUS
THE MAIN CORTICAL MOTOR SYSTEM USES THE CORTICOBULBAR AND CORTICO-
SPINAL TRACTS FOR EXECUTION OF VOLUNTARY MOVEMENTS. LESION OF THE UPPER MOTOR NEURON PATHWAYS RESULTS IN SPASTIC PARALYSIS, EXAGGERATED STRETCH REFLEX AND SOME ABNORMAL REFLEXES. CEREBELLAR DISORDERS CHANGE THE RATE, DIRECTION, RANGE AND FORCE OF MOVEMENTS. LESIONS OF THE BASAL GANGLIA ARE MANIFESTED IN DYSKINESIA
www.itk.ppke.hu
THE MOTOR CORTEX
THE MOTOR CORTEX IS COMPRISED OF THE PRECENTRAL GYRUS, AS THE PRIMARY MOTOR CENTER, THE SUPPLEMENTARY MOTOR CORTEX AND THE PREFRONTAL MOTOR CORTEX AND CERTAIN PARIETAL LOBE REGIONS. THE MUSCLE GROUPS OF THE BODY ARE REPRESENTED IN A SOMATOTOPIC FASHION IN THE PRIMARY
MOTOR CORTEX (MOTOR HOMUNCULUS) PRECENTRAL GYRUS
SUPPLEMETARY MOTOR CORTEX
PREMOTOR CORTEX
NOTE THE LARGE REPRESENTATIONS OF THE HAND AND THE TONGUE
11/25/2011. TÁMOP – 4.1.2-08/2/A/KMR-2009-0006 5
THE CORTICOBULBAR AND CORTICOSPINAL PROJECTIONS
THE DESCENDING CORTICOBULBAR MOTOR FIBERS SUPPLY MOTONEURONS OF THE BRAIN STEM, WHILE THE CORTICOSPINAL PROJECTION THAT SPLITS AT THE LEVEL OF THE MEDULLA FEEDS THE LOWER MOTONEURONS OF THE SPINAL CORD VIA THE LATERAL AND ANTE- RIOR CORTICOSPINAL TRACTS. NOTE THE
BILATERAL INNERVATION OF THE TRIGEMINAL MOTOR NUCLEUS IN THE PONS. THE CROSSING OF THE MAJORITY OF CORTICOSPINAL AXONS IN THE MEDULLA IS HIGHLIGHTED BY PINK SHADOW
www.itk.ppke.hu
COURSE OF THE DESCENDING PYRAMIDAL PATHWAY
F
INTERNAL CAPSULE
SPINAL CORD MEDULLA MIDBRAIN
PONS
MEDULLA AT CROSSING SITE
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CORTICOSPINAL PROJECTION WITHIN THE INTERNAL CAPSULE
FIGURE A DEPICTS THE DOWNSTREAM COURSE OF CORTICOSPINAL FIBERS. NOTE THE CONVERGENCE (HIGHLIGHTED IN GREEN) TOWARD THE INTERNAL CAPSULE.
FIGURE B ILLUSTRATES THE PYRAMIDAL TRACT IN THE GENU OF THE CAPSULE WEDGED BETWEEN THE ANTERIOR AND POSTERIOR THALAMIC PROJECTIONS. THE OPTIC RADIATION IS SHOWN IN GREEN
ANTERIOR THALAMIC PROJECTION
POSTERIOR THALAMIC PROJECTION
OPTIC RADIATION PYRAMIDAL TRACT
A B
www.itk.ppke.hu
LATERAL VESTIBULAR NUCLEUS F
ILLUSTRATION OF SOME DESCENDING UPPER MOTONEURON SYSTEMS
PONTINE RETICULAR FORMATION
LATERAL
CORTICOSPINAL TRACT
ANTERIOR
CORTICOSPINAL TRACT
MEDULLARY RETICULAR FORMATION
IN ADDITION TO PATHWAYS SHOWN IN THE FIGURE, THE SUPERIOR COLLICULI,
THE NUCLEUS RUBER, THE INFERIOR OLIVE, NORADRENERGIC AND SEROTONERGIC CELLS GROUPS OF THE BRAIN STEM ALSO SEND PROJECTIONS TO THE CORD
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NEURONAL LINKS AND LOCAL CIRCUITS OF THE STRIATUM
THE PUTAMEN PART OF THE CAUDATE NUCLEUS RECEIVES INFORMATION FROM THE THALAMUS, CEREBRAL CORTEX, MESENCEPHALON AND
SUBSTANTIA NIGRA. GLUTAMATE INPUTS FROM THE THALAMUS AND CORTEX ARE EXCITATORY, THE DOPAMINE INNERVATION FROM THE SUBS- TANTIA NIGRA IS SUPPOSED TO BE INHIBITORY.
THE INPUTS ARE RECEIVED BY SPINY ENKE- PHALIN- AND SUBSTANCE P-ERGIC NEURONS.
THEY TRANSMIT THE PROCESSED INFORMATION TO THE GLOBUS PALLIDUS (PALLIDUM) THAT IS THE MAIN EFFERENT STRUCTURE OF THE
SYSTEM. IT SENDS PROJECTIONS TO THE
SUBSTANTIA NIGRA AND DIFFERENT NUCLEI OF THE THALAMUS. THE THALAMUS FEEDS THE INFORMATION BACK TO THE CORTEX
ENKEPHALIN
www.itk.ppke.hu
ROLE OF THE STRIATUM IN THE MOTOR SYSTEM
4
8 7 5
2
3
1
1. CEREBRAL CORTEX 2. PUTAMEN
3. PALLIDUM
4. SUBSTANTIA NIGRA
5. SUBTHALAMIC NUCLEUS 6. THALAMUS (VL)
7. THALAMUS (INTRALAMINAR) 8. PEDUNCULOPONTINE NUCLEUS
6
NOTE, THAT THE INFORMATION PROCESSED IN THE STRIATUM IS TRANSMITTED TO THE CEREBRAL CORTEX. THE CORTEX INCORPORATES THE STRIATAL MESSAGE AND CONVEYS THE
OUTGOING MOTOR INFORMATION VIA THE CORTICOSPINAL TRACT
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ROLE OF CEREBELLUM IN CONTROL OF MOVEMENT
1 2
3
4
7 8
11
A
B 10
9
1. CEREBRAL CORTEX 2. PONTINE NUCLEI 3. INFERIOR OLIVE 4. THALAMUS (VL) 5. RED NUCLEUS
6. RETICULAR FORMATION 7. VESTIBULAR NUCLEI 8. VESTIBULAR GANGLION 9. VESTIBULOCEREBELLUM 10. SPINOCEREBELLUM 11. NEOCEREBELLUM
5
6 I. CORTICOSPINAL
II. RUBROSPINAL III. RETICULOSPINAL IV. VESTIBULOSPINAL
II.
III.
IV.
C
A. GLOBOSE NUCLEUS B. FASTIGIAL NUCLEUS C. DENTATE NUCLEUS
INTEGRATION OF THE DIFFERENT MOTOR SYSTEMS
www.itk.ppke.hu
CORTEX MOTOR CORTEX
STRIATUM
THALAMUS VA/VL
PONS S. NIGRA
CEREBELLUM
N. RUBER
SPINAL CORD
VESTIBULAR NUCLEI INF. OLIVE
RETICULAR FORMATION
LOWER
MOTONEURON MUSCLE
PALLIDUM
