1. Motor control Neurophysiology page 1
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

2. Motor control Contents Is nervous system (NS) necessary for behaviour?
Neurophysiology
Motor control
page 2
Contents
Is nervous system (NS) necessary for behaviour?
What was first? Sensory neurone or motor neurone?
NS phylogenesis with regard to motor control
Basic units that control movement in mammals
Logic of motor control. Fusimotor system.
Direct control by motor cortex
Basal ganglia = plans of actions
Cerebellum – a mystery?
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

3. Motor control Is nervous system necessary for behaviour?
Neurophysiology
Motor control
page 3
Is nervous system necessary for behaviour?
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

4. Behaviour was first, neurones were second
Neurophysiology
Motor control
page 4
Behaviour was first, neurones were second
Protists have no neurones, yet they display:
Active predation
Phototaxis
Gravitaxis
Chemotaxis
Mechanoresponsiveness
Single-cell organisms perform both sensory and
motor function
Cilia-driven locomotion
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

5. What was first? Sensory neurones or motor neurones?
Neurophysiology
Motor control
page 5
What was first? Sensory neurones or motor neurones?
(Sensory receptor)-like neurones controlling
non-neural motility of primitive ciliated
organisms => Sensory neurones were first
Sensory-motor
unit
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

6. Motor neurones have evolved along with muscle cells.
Neurophysiology
Motor control
page 6
Motor neurones have evolved along with muscle cells.
Muscle cells are controlled by motor neurones
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

7. Motor control Cnidaria Neurophysiology page 7
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

8. Motor control Molluscs – ganglia Pedal ganglia Neurophysiology page 8
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

9. F M H Output Motor control Vertebrate brain Neurophysiology page 9
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

10. Motor control Vertebrate brain Brain of the tiger salamander
Neurophysiology
Motor control
page 10
Vertebrate brain
Brain of the tiger salamander
C. J. Herrick
( )
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

11. Motor control Vertebrate brain Brain of the tiger salamander
Neurophysiology
Motor control
page 11
Vertebrate brain
Brain of the tiger salamander
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

12. Motor control Levels of mammalian motor control Motor cortex
Neurophysiology
Motor control
page 12
Levels of mammalian motor control
Motor cortex
Basal ganglia
Brain stem
Cerebellum
Spinal cord
Motor unit
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

13. Motor control Spinal cord Sensory & motor nerves
Neurophysiology
Motor control
page 13
Spinal cord
Sensory & motor
nerves
31 pairs of spinal nerves
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

14. Motor control Spinal cord α motor neurone γ motor neurone
Neurophysiology
Motor control
page 14
Spinal cord
α motor neurone
γ motor neurone
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

15. Motor control Muscle fibre Muscle Muscle fasciculus Muscle fibre
Neurophysiology
Motor control
page 15
Muscle fibre
Muscle
Muscle fasciculus
Muscle fibre
Myofibril
α motor
neurone
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

16. Motor control Motor unit = α motor neurone + extrafusal muscle fibres
Neurophysiology
Motor control
page 16
Motor unit = α motor neurone + extrafusal muscle fibres
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

17. Motor control Muscle structure Extrafusal fibres Intrafusal fibres
Neurophysiology
Motor control
page 17
Muscle structure
Extrafusal
fibres
Intrafusal
fibres
Muscle spindle
Alfa
motoneurone
Gamma
motoneurone
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

18. Motor control Proprioception Muscle spindle Sensory ending
Neurophysiology
Motor control
page 18
Proprioception
Muscle spindle
Sensory ending
Motor ending (γ)
Golgi tendon organ
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

19. Motor control Golgi tendon organ Neurophysiology page 19
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

20. Motor control Muscle spindle Neurophysiology page 20
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

21. Neurophysiology
Motor control
page 21
Muscle spindle - Stretch reflex vs. Voluntary contraction
Spindle lengthened
α and γ co-activation
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

22. Motor control Spinal reflexes Afferent inhibition Stretch reflex
Neurophysiology
Motor control
page 22
Spinal reflexes
Afferent inhibition
Stretch reflex
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

23. Motor control Spinal reflexes Recurrent inhibition Tendon reflex
Neurophysiology
Motor control
page 23
Spinal reflexes
Recurrent inhibition
Tendon reflex
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

24. Motor control Spinal reflexes Flexor withdrawal reflex Neurophysiology
page 24
Spinal reflexes
Flexor withdrawal reflex
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

25. Motor control Levels of mammalian motor control Motor cortex
Neurophysiology
Motor control
page 25
Levels of mammalian motor control
Motor cortex
Basal ganglia
Brain stem
Cerebellum
Spinal cord
Motor unit
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

26. Motor control Motor cortex Motor homunclus Neurophysiology page 26
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

27. Motor control Motor cortex Primary - agranular Premotor - dysgranular
Neurophysiology
Motor control
page 27
Motor cortex
Primary - agranular
Premotor - dysgranular
Supplementary - dysgranular
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

28. Motor control Motor cortex connections; Tracts MII PM MI SI av talamus
Neurophysiology
Motor control
page 28
Motor cortex connections; Tracts
MII PM MI SI
av talamus
vl talamus
pallidum
n. ruber
cerebellum
pont. rf
medul. rf
spinal cord
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

29. Motor control Pyramidal tract Neurophysiology page 29
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

30. Motor control Red nucleus – a relict Corticorubral tract
Neurophysiology
Motor control
page 30
Red nucleus – a relict
Corticorubral
tract
Nucleus ruber is
under the control of
the cerebellum
Rubrospinal tract
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

31. Motor control Brain stem control of posture Pontine reticular nuclei
Neurophysiology
Motor control
page 31
Brain stem control of posture
Pontine
reticular
nuclei
Stimulates antigravity
muscles.
Afferent connections:
All vestibular nuclei
Cerebellum
Vestibular
nuclei
Relaxes antigravity
muscles.
Afferent collaterals from:
- Pyramidal tract
- Rubrospinal tract
- Other motor pathways
Medullary
reticular
nuclei
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

32. Motor control How to explain voluntary movements? Neurophysiology
page 32
How to explain voluntary movements?
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

33. Motor control Motor cortex Organisation of CNS
Neurophysiology
Motor control
page 33
Motor cortex
Organisation of CNS
Cerebral cortex = neural substrate for mnemonic representation
of the external and inner world
Sensory signals lose meaning unless they can control behaviour
Each structure has an output
Motor as well as sensory cortical areas represent (code, remember)
real ‘objects’. Similar to primary sensory cortices that code sensory
primitives, primary motor cortex codes motor ‘primitives’ – muscles.
The premotor and suplementary motor cortices code for more
abstract motor ‘objects’, e.g. movements.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

34. Motor control Motor cortex Organisation of CNS
Neurophysiology
Motor control
page 34
Motor cortex
Organisation of CNS
Cerebral cortex = neural substrate for mnemonic representation
of the external and inner world
Sensory signals lose meaning unless they can control behaviour
Each structure has an output
Sensory cortical areas send their output to the associative areas
which represent reality in a complex and abstract way. As the
overall goal is to control behaviour, these cortices send their
output to areas that store plans of actions, patterns of behaviour.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

35. Motor control Motor cortex Organisation of CNS
Neurophysiology
Motor control
page 35
Motor cortex
Organisation of CNS
Cerebral cortex = neural substrate for mnemonic representation
of the external and inner world
Sensory signals lose meaning unless they can control behaviour
Each structure has an output
Primary sensory cortical areas are a representational substrate
located closer to the input side of information flow.
Motor cortex is a representational substrate closer to the output
side, i.e., closer to structures that control behaviour.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

36. Motor control Motor cortex Organisation of CNS
Neurophysiology
Motor control
page 36
Motor cortex
Organisation of CNS
Cerebral cortex = neural substrate for mnemonic representation
of the external and inner world
Sensory signals lose meaning unless they can control behaviour
Each structure has an output
The CNS structures, activated in this order:
Sensory neurone, Thalamus, Primary sensory cortex, Higher-order
sensory cortices, Associative cortical areas, Prefrontal cortex,
Striatum, Pallidum, Thalamus, Motor cortex, and Motor neurone,
can be considered an improved reflex arc (conditioned)
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

37. Motor control Phylogenetic principle of inteligence
Neurophysiology
Motor control
page 37
Phylogenetic principle of inteligence
Thalamo-cortico-striatal system
Mesencephalon
Medulla
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

38. Motor control From stimulus to voluntary action
Neurophysiology
Motor control
page 38
From stimulus to voluntary action
Sensory organ – stimulus detection, registration of reality
Thalamus - ?
Primary sensory cortex – sensory primitives
Higher-order sensory cortices – abstract representations
Associative cortical areas – abstract non-sensory representations
Prefrontal cortex – interpreter of information
Striatum – database of efferent programs (action templates)
Pallidum – ‘point of no return’, release vs. termination of action
Thalamus - ?
Motor cortex – representation of motor units
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

39. Motor control Basal ganglia Striatum = caudate nucl. + putamen
Neurophysiology
Motor control
page 39
Basal ganglia
Striatum
= caudate nucl. + putamen
Globus pallidus
Nucleus accumbens
Nucleus subthalamicus
Substantia nigra
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

40. Motor control Basal ganglia Neurophysiology page 40
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

41. Motor control Basal ganglia Neurophysiology page 41
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

42. Motor control Motor cortex connections; Tracts MII PM MI SI av talamus
Neurophysiology
Motor control
page 42
Motor cortex connections; Tracts
MII PM MI SI
av talamus
vl talamus
pallidum
n. ruber
cerebellum
pont. rf
medul. rf
spinal cord
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

43. Motor control Cerebellum
Neurophysiology
Motor control
page 43
Cerebellum
Motor control (both voluntary and automatic) can proceed without the cerebellum.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

44. Motor control Cerebellum Neurophysiology page 44
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

45. Motor control Neurophysiology page 45
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

46. Motor control Neurophysiology page 46
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

47. Motor control Neurophysiology page 47
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

48. Motor control Neurophysiology page 48
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

49. Neurophysiology
Motor control
page 49
The cerebellum has probably evolved as a means of maintaining our body in optimal orientation relative to gravity under all circumstances through motor control.
In support of this hypothesis is the fact that the oldest part of the cerebellum is the flocculus which responds to vestibular signals by maintaining body balance and corresponding eye movements.
Mozek vyda pokyn. Ale potrebuje zpetnou vazbu.
Cestou ze skolky kup chleba.
Co vidis? U Kalicha. Zaboc doleva!
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

50. Motor control Cerebellum Anatomical division Anterior lobe
Neurophysiology
Motor control
page 50
Cerebellum
Anatomical division
Anterior lobe
Posterior lobe
Flocculonodular lobe
‘Functional’ division
Vestibulocerebellum
(flocculonodular l.)
Spinocerebellum
(medial part)
Cerebrocerebellum
(lateral part)
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

51. Motor control Cerebellum – fine neural structure Purkynje cell
Neurophysiology
Motor control
page 51
Cerebellum – fine neural structure
Purkynje cell
Granule cell (3/4 of all)
Parallel fibre
Climbing fibre
Mossy fibre
Deep cerebellar nucleus
Inferior olive
(in the medulla)
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

52. Motor control Cerebellum – afferent connections
Neurophysiology
Motor control
page 52
Cerebellum – afferent connections
Cortico-ponto-cerebellar
pathway
Olivocerebellar tract
(climbing fibres from
the inferior olive)
Spinocerebellar
pathway
Vestibulocerebellar
pathway
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

53. Motor control Cerebellum – efferent connections Thalamus Basal ganglia
Neurophysiology
Motor control
page 53
Cerebellum – efferent connections
Thalamus
Basal
ganglia
Nucleus
ruber
Nucleus
reticularis pontis
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

54. Motor control Cerebellar lesion Cerebellar activation during speaking
Neurophysiology
Motor control
page 54
Cerebellar lesion
Cerebellar activation during
speaking
Play from web
Play from web
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

55. Motor control Cerebellum
Neurophysiology
Motor control
page 55
Cerebellum
The cerebellum is probably one of two elementary feedback mechanisms of the motor system that adjust movements.
The first is the fusimotor system (gamma motoneurone) which functions on the basis of spinal feedback.
The second is the cerebellum that works like software. It adjusts signals – that are sent to muscles by the motor cortex – in a way that the result exactly corresponds to the wanted movement.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

56. Motor control Play from web Neurophysiology page 56
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

57. Motor control The end Neurophysiology page 57
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

58. Motor control Neurophysiology page 2
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

59. Motor control coactivation of the alpha and gamma motor neurons
Neurophysiology
Motor control
page 2
coactivation of the alpha and gamma motor neurons
coactivation keeps the muscle spindle reflex from opposing the muscle contraction
Activation of muscle spindles on opposite sides of a joint elicits reflexes on both sides and fixates it.
The purpose of patelar reflex test is to determine how much background excitation, or “tone,” the brain is sending to the spinal cord
Golgi tendon organ: reflex provides a negative feedback mechanism that prevents the development of too much tension on the muscle
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

60. Motor control Ovládání svalu – fusimotorický systém Neurophysiology
page 2
Ovládání svalu – fusimotorický systém
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

61. Motor control Ovládání svalu – fusimotorický systém Svalové vřeténko
Neurophysiology
Motor control
page 2
Ovládání svalu – fusimotorický systém
Svalové vřeténko
signalizuje natažení
(délku) intrafusálního
vlákna.
Golgiho šlachové
tělísko
signalizuje napětí
svalu.
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad

62. Motor control Ovládání svalu – fusimotorický systém Alfa motoneuron
Neurophysiology
Motor control
page 2
Ovládání svalu – fusimotorický systém
Alfa motoneuron
aktivuje kontrakci
svalu (extrafusálních
vláken)
Gamma motoneuron
aktivuje kontrakci
intrafusálních vláken
Department of Physiology, 2nd Faculty of Medicine, Charles University Copyright © 2011 Luděk Nerad