The document discusses sensory-motor processing in the planning and execution of movement, highlighting the hierarchical structure of the motor control system within the brain. It details the roles of different brain regions, including the cerebral cortex and brain stem, in motor functions and emphasizes the importance of both internal models and sensory feedback for effective movement. Additionally, the document examines implications for understanding movement disorders such as Parkinson's disease and stroke, along with relevant experimental findings.

1. Sensory-motor processing in planning and execution of
movement
Subhadeep Dutta Gupta
M.Phil Scholar
Department of Neurophysiology, NIMHANS

2. j
Sea squirt (Ascidiacea)

3. Introduction
• Movement is an important feature of living organism.
• All interaction with the surrounding world is through motor
system.
• The motor system continues to develop through maturation
of neuronal circuitry and by learning through different motor
activities during the first 15 years of life.

4. Hierarchy of motor control:
• Background:
 Jackson, (1889) : higher motor centers controlling simple movements.
 William James, (1890) : voluntary movement is secondary to reflexive
actions, and involves anticipatory image.
 C. Sherrington, (1906) : distinguished between upper & lower motor
neurons.
 Keele, (1968) : ordered nature of high level motor programs for feed-
forward control of movements.

5. 3 levels in hierarchy of motor control:
h Cerebral cortex:
-- primary motor & sensory cortex, premotor cortex, supplementary
motor cortex
-- mediated by Pyramidal system.
 Brain Stem:
-- Extrapyramidal system.
 Spinal cord:
-- ‘final common pathway’ modulated by higher centre.
-- executive centre for reflexes & pattern generation.

6. d
Organization of the motor system:

7. Cerebral Cortex: Representation of the motor
functions:
• J.H Jackson:
-- Specific part of the cortex has a causal role in movement.
• Fritsch, Hitzig, Ferrier:
-- Electrical stimulation at specific region of the cortex evoked
movements in contralateral body parts.
-- Lesion of that region caused loss of motor control of the
specific body part.

8. Cerebral Cortex:
Sensory & Motor Homunculus:

9. Cytoarchitecture of motor cortex :
-- Primary motor cortex is agranular.
-- Layer IV (cell-packed granular layer) is very
thin or nearly absent.
-- Layer V (descending output layer) is thicker
& contains the giant Betz cells.
-- These neurons makes up around 30% of the
fibres in the cortico-spinal tract.
Betz cells of layer V

10. Organization of precentral motor area:
--Principles of Neural Science, 5th Edn

11. Internal Model:
• Postulated neural process that simulates the response of the
motor system in order to estimate the outcome of a motor
command.
• The motor system makes use of internal models in order to
control the musculoskeletal system during rapid, skilled, motor
behaviour.
• Ex – Size Mass estimation
-- Science, 269, 1880-1882 (1995).

12. Processing of sensory information in the cerebral cortex
--Principles of Neural Science, 5th Edn

13. Cross talk of association areas :
--Principles of Neural Science, 5th Edn
Motor & executive control
Emotional responses

14. • Parietal Association Cortex:
-- key role in the visual guidance of motor behaviour.
-- spatial perception & cognition.
-- suited for such computation as it is connected with visual,
somatosensory & motor areas of cortex.
• Damage:
-- Ideomotor apraxia
-- Impaired speech repetition
-- Personal neglect syndrome

15. ‘Binding’
Conceptual representation of feature binding & representation:
Trends in Neurosciences, 2013(36)3

16. • Temporal Association Cortex:
-- Object recognition and semantic memory.
 Inferotemporal neurons :
-- are sensitive to the shape, colour, and texture of an object.
-- insensitive to size and location of the objects.
-- activity is not influenced by the motor behaviour of the animal.
• Damage:
-- semantic dementia Visual object agnosia

17. Connection between prefrontal & motor cortex:
--Principles of Neural Science, 5th Edn
Emotional & cognitive processes in the PFC controls the motor
behaviour

18. Primary Motor Cortex:
• Primary motor cortex neurons fire 5-100 msec before the onset of a
movement.
• Primary motor cortex encodes the force of a movement (Evarts et
al., 1968).file:///D:/Presentation%20on%20Movement/Videos/1.Force%20of%20movement.swf
• It encodes the direction of movement (Georgopoulas et al., 1982).
-- Many neurons are selective for a particular direction of
movement. file:///D:/Presentation%20on%20Movement/Videos/2.Direction%20of%20mov ement.swf
• It encodes the extent of movement.
• It also encodes the speed of movement. file:///D:/Presentation%20on%20Movement/Videos/3.Speed%20of%20movement.swf
-- Bell shaped curve

19. • Premotor cortex neurons signal the preparation for movement
(Weinrich and Wise,1982). file:///D:/Presentation%20on%20Movement/Videos/4.Pr eparation%20of%20movement.swf
-- Motor- set neurons ‘Go’ signal.
• Premotor cortex is sensitive to the behavioural context of a
particular movement (Iacoboni et al., 2005).file:///D:/Presentation%20on%20Movement/Videos/5..Behavior al%20context.swf
• Premotor cortex signals correct and incorrect actions.
Premotor Cortex:

20. g• Premotor cortex neurons signal various sensory aspects
associated with particular motor acts.
-- Some neurons fire when a subject is performing a particular
action.
-- Same neuron fires selectively when the subject sees
someone performing a particular action.
-- It also fires selectively even without a visual or motor
activity.
-- Concept of Mirror & Cannonical Neurons (Rizzolatti et al.,
1996)

21. Supplementary Motor Area:
• SMA is involved in the transformation of
kinematic to dynamic information.
• SMA responds to sequences of movements
and to mental rehearsal of sequences of
movements (Roland et al., 1980).file:///D:/Presentation%20on%20Movement/Videos/6.Mental%20rehearsal.swf

22. Descending pathways that mediate motor functions:
--Fundamental Neuroscience; 3rd Edn

23. Corticospinal system:

24. The Malleable Motor Map:
-- Annu. Rev. Neurosci. 2000. 23:393–415

25. Phantom Limb & Mirror Therapy:
Amputated Limb
Intact Limb

26. Motor control centers in the brain stem:
The major brain stem nuclei sending fibers to the spinal cord.
--The Central Nervous System,4th Edn

27. h• Hans Kuypers classification:
 Medial Brain stem pathway
-- Vestibulospinal tract
-- Reticulospinal tract
-- Tectospinal tract
 Lateral Brain stem pathway
-- Rubrospinal tract

30. Experimental evidence:
Transection of the direct pathway in Rhesus
monkeys (with intact Indirect pathways):
 difficulty in using the distal parts of their limbs.
 unable to reach toward & pick up food with their fingers
 they used the entire arm to sweep the food toward
them.
-- Lawrence & Kuypers, 1968

31. --Principles of Neural Science, 5th Edn

32. Motor control at Spinal level:
 Reflex:
-- Automatic, stereotyped movement in response to stimulation of
peripheral receptors.
-- integrated by centrally generated motor commands into complex
adaptive movements.

33. Central pattern generator:
• Neural network within CNS that give rise to rhythmic
motor activity independent of sensory inputs.
• Ex- Motor behavior such as respiration, walking,
feeding, swimming, flying.
• Studied extensively in lampreys, snails, leeches, flies,
frogs, chicks etc.

34. EMG Recording in Lobster:
K
K
K
K
K
k
k
H
H
H
H
H
H
H
H
H
H
-- The Journal of Neuroscience, 1987, 7(7), 2097-2112.
Lateral Pyloric Neurons (LP)
Pyloric Neurons (PY)
Pyloric Dilator Neurons (PD)
Lateral Ventricular Nerve (lvn)

35. Generation of Fictive locomotion:
H
H
H
H
H
H
H
H
H
H
H
H
h
H
H
H
H
H
H
H
H
H
H
-- J Neurophysiol 82:2029-2038, 1999.

36. Mechanism of swimming in lamprey:
Glutamate The membrane depolarizes
Na+ and Ca2+ flow into the cell through the NMDA receptors
Ca2+ activates K+ channels
K+ flows out of the cell
The membrane hyperpolarizes
Ca2+ stops flowing into the cell
K+ channels close
The membrane depolarizes, and the cycle repeats.
-- Neurosci. Lett. 89, 31–35., 1987

37. Rhythmic activity in a spinal interneuron

38. Sensorimotor integration in movement disorders:
 Parkinson’s Disease:
• Classical view:
• -- dysfunction of the basal ganglia-motor cortex
circuits.
• BG involved in:
• somatosensory discrimination
• visual perception
• spatial working memory
-- Curr Opin Neurobiol 1997; 7:157-63.

39. • When external, visual or auditory cues are
provided, substantially improvement of specific
features of Parkinsonian bradykinesia was noted.
• Deficient internal cueing mechanism to
discharge successive stages of a movement
sequence ????
-- Mov Disord 2000; 15: 879-83.

40.  Stroke:
• Sudden focal neurological deficit due to a
cerebrovascular abnormality.
• Decreased plasticity in affected region while an
increase of sensorimotor integration process
happens in non-affected regions.

41. • Restraint of the intact limb over an extended
period, in combination with a large number of
repetitions of task-specific training of the
affected limb.
Positive outcome
-- Lancet Neurol 2008; 7: 33-40.

42. Scheme of interaction between different motor
centers
-- Fundamental Neuroscience; 3rdEdn

43. Bibliography:
• Principles of Neural Science, 5th Edition, Eric Kandel.
• Fundamental Neuroscience, 3rd Edition, Larry Squire
• Neuroscience, 3rd Edition, Dale Purves
• The Central Nervous System, 4th Edition, Per Brodal
• Neuroscience, 3rd Edition, Mark Bear
• Modulation of the lobster pyloric rhythm by the peptide proctolin, The Journal of
Neuroscience, 1987, 7(7), 2097-2112.
• The mammalian central pattern generator for locomotion, Brain Research Reviews,
2009 (62) 45-56.
• Interaction Between Disinhibited Bursting and Fictive Locomotor Patterns in the
Rat Isolated Spinal Cord, J Neurophysiol ,1999, (82) 2029-2038.
• Jerome N. Sanes and John P. Donoghue, Plasticity & Primary cortex, Annu. Rev.
Neurosci., 2000. (23)393–415.

44. • Brown LL, Schneider JS, Lidsky TI. Sensory and cognitive functions of the basal
ganglia. Curr Opin Neurobiol 1997; 7: 157-63.
• Marchese R, Diverio M, Zucchi F, Lentino C, Abbruzzese G. The role of sensory
cues in the rehabilitation of Parkinsonian patients: a comparison of two
physical therap. Mov Disord 2000; 15: 879-83.
• Wolf SL, Winstein CJ, Miller JP, Thompson PA, Taub E, Uswatte G, et al.
Retention of upper limb function in stroke survivors who have received
constraint-induced movement therapy: the EXCITE randomised trial. Lancet
Neurol 2008; 7: 33-40.
• D.M. Wolpert, Z. Ghahramani and M.I. Jordon. An internal model for
sensorimotor integration. Science, 269, 1880-1882 (1995).
• Grillner, S., Buchanan, J.T., Lansner, A., 1988. Simulation of the segmental burst
generating network for locomotion in lamprey. Neurosci. Lett. 89, 31–35.
• M. Larkum. A cellular mechanism for cortical association.Trends in
Neurosciences, March 2013, Vol. 36, No. 3.

45. d
“All mankind can do is to move things…
whether whispering a syllable or felling
a forest.”
--Sir Charles Scott Sherrington

46. h
Thank You !!!!