1. Sensory Stimulation in Neurological Rehabilitation
Prof. A.V. SRINIVASAN.
M.D, D.M, PhD ,
F.I.A.N, F.A.A.N
EMERITUS PROFESSOR OF NEUROLOGY
FORMER HEAD AND PROFESSOR OF NEUROLOGY
Institute of Neurology
Chennai
The sign wasn ’
t placed there
By the Big Printer in the sky
Sensory Stimulation in
Neurological Rehabilitation

3. NEU CON NeuCon CONTROVERSIES IN NEUROLOGY APRIL 3-4, 2010 G.ARJUNDAS

4. SHRI US MEHTA ORATION

5. Thomas Elbert Basic Principles
Cortical representation expands linearly with use.
Synchronous inputs lead to fusion of cortical zones
Asynchronous inputs lead to segregation of cortical zones.
Disuse or De-afferentation leads to invasion of
unused cortical area by nearby neurons.

6. Sensory modulation in spatial neglect
Novel Techniques
Peripheral somatosensory- Magnetic stimulation
Repetitive optokinetic stimulation
Neck Vibration training
Drug Treatment is currently unsuccessful

7. Sensory modulation and Stroke
Rehabilitation aimed to increase use of paretic hand
Virtual reality
Motor imagery
Prof. V.S..Ramachandran’s virtual reality box
Phantom limb phenomenon

8. Other techniques Caloric tests for balance
Brings awareness of illness to patient.
Kinesthetic, visual, and auditory cues to improve Parkinsonian gait.

9. INTERMANUAL REFERRAL OF SENSATION AND EXTINCTION OF PAIN IN PERIPHERAL AND CENTRAL LESIONS OF SOMATO SENSORY SYSTEM

10. BACKGROUND
Allesthesia and extinction of referral sensation in brachial plexus lesions
A.V. Srinivasan and V.S. Ramachandran et al (1998)
Intermanual referral of sensations after central lesions of the somato sensory system
K. Sathian et al (2000)

11. METHODS 8 patients (19-51 years) Brachial plexus lesion – one
Amputation – two
Stroke – five
Patients were video filmed in the movement disorder clinic. Pinprick, cold, vibration and kinesthesis were tested
MRI & ENMG in all cases

12. CENTRAL LESION Stroke Thalamic stroke - three Temparo parietal - two
Three to four months later
Ipsilateral arm - no referral to leg

13. STROKE Contd…
Intense pressure on the normal hand resulted in extinction of pain in the stroke side
Pain returned within one minute of the pressure
Intense pressure improved sensory and motor phenomenon

14. AMPUTATION
Both the patients (below elbow & knee amputation) showed intermanual referral of sensation within 10 days. The referred sensations of touch and vibration lacked spatial organization and poor localization with a relatively high threshold

15. CASE VIGNETTE (BRACHIAL PLEXUS LESION)
21 year old girl, after total brachial plexus lesion was examined 6 months, 1 ½ & 2 ½ years after the lesion
She had sensations intermanually referred in a topographically organized manner in the phantom limb

16. INTERMANUAL REFERAL AND EXTINCTION OF PAIN SENSATION
Hemiparesis with hemisensory deficit
Amputation
Brachial plexus
Spatial organi-sation
Poor
Excellent
Localisation
Good
Time of occurance
After 3 to 4 months
Immediate with in 7 days
Immediate with in 7days
Pain
Extinction
After a delay of
3 - 5 seconds
Immediate

17. DISCUSSION Anatomical facts In 2a & 2b the receptive fields are larger
1. Primary somato sensory area 3b
2. A. Primary somato sensory area 1 & 2
2. B. Second somato sensory cortex and
parietal operculum
In 2a & 2b the receptive fields are larger
bilateral and callosal connection are
abundant

18. DISCUSSION Contd…
Contralateral referral of sensations was not found in normal subjects or in hemiparetic patients without hemi sensory loss
Neural mechanisms for perceptual alteration not clear

19. DISCUSSION Contd…
It appears that a decrease in somatosensory input to one cerebral hemisphere from the contralateral hand allows responsiveness of neurons in this hemisphere to moderately intense tactile stimuli on the ipsilateral hand to exceed perceptual threshold (which does not normally occur).

20. CONCLUSION
Intermanual referral & extinction of pain occurred immediately in amputation and brachial plexus lesions and after a delay in stroke
Intermanual referral of sensation occurred topographicaly organised manner in brachial plexus lesions but not in amputation and stroke

21. Hemineglect An Interesting Case from Prof.A.V.Srinivasan’s Unit

22. Can the mind believe what the eye sees ?
On vision, visuospatial dysfunction and body image perception in right hemispherical dysfunction
Dr.K.Bijoy Menon (Senior Resident)
Dr.Sundar, Dr.Saravanan, Dr.Ramakrishnan
Dr.Nithyanandan (Asst.Prof) ,
Prof. A.V.Srinivasan

23. We thank Prof. V.S.Ramachandran, M.D., Ph.D., Director
Centre for Brain and Cognitive Sciences
University of California, San Diego, USA

24. Indrani. 50 year old female
Presents with sudden onset of weakness of left upper and lower limb
O/E.
Conscious, oriented to time, place and person
Mild left UMN facial paresis
Left hemiplegia
All peripheral pulses palpable

25. CT Brain – P – Shows a (R) Occipitotemporal infarct

26. Higher mental function evaluation
MMSE : 28/30
She was very attentive and quite clear in her conversation with us, though she would be complaining of a vague left sided shoulder pain
On lobar testing, she had
Left visual neglect with (L) hemianopia
No auditory neglect
Absent sensory perception in (L) upper limb and (L) tactile neglect in the lower limb

29. On cold caloric tests and its effect on neglect

30. Video of Neglect

31. Video of caloric test and Nystagmus

32. Video of disappearance of neglect

33. Mirror Agnosia on the Right
On ‘ Mirror Agnosia’
Mirror Agnosia on the Right

34. After caloric test, Mirror Agnosia on the Left

35. ‘Mirror Agnosia’ to front

36. On Anosognosia, Body neglect (Hemisomatognosia) and somatoparaphrenia
Anosognosia – our patient has it
Body neglect by Bisiach’s test – our patient does not have it
Somatoparaphrenia – our patient has it

37. Somatoparaphrenia

38. On the somatophrenic arm and mirrors

39. On Allesthesia, tactile neglect and ‘blind touch’
‘Touch your left arm’ Bisiach’s test of body neglect.
Absent proprioception and touch in the left upper limb
Patient is still able to touch her left arm whatever position the examiner keeps the arm in.

40. Blind Sight Vs Blind Touch

41. On visual imagery, neglect and caloric tests
Bisiach’s test
Our test

42. Results

43. Blind Sight And Blind Touch
Unconscious awareness in a person with
Blind Sight
And
Blind Touch
Conscious mind and unconscious mind
Theories of consciousness and the soul.

44. Thank You