Dr. Lofti Merabet discusses the incredible adaptability of the brain with the loss of one or more senses. (NDA International Conference, 2009)

1. The Boston Retinal Implant Project Center for Noninvasive Brain Stimulation
Center for Innovative Visual Rehabilitation Harvard Medical School
Boston VA Medical Center Beth Israel Deaconess Medical Center
www.bostonretinalimplant.org www.tmslab.org

3. Are the Blind Really Better? Auditory
Tactile
1.5
JVP Domes
1.4
Threshold
1.3
1.2
1.1
1.0
0.9 Gougoux et al. Nature, 2005
Blind Sighted
1.2
1.1
Verbal Memory
Threshold
1
0.9
0.8
0.7
Reading Homol Non-Dom Non-Dom
Homologous
van Boven et al. Neurology 2000
Amedi et al. Nat Neurosci 2003; 2004

4. "we only use about 30% of our brains"…???

5. TOUCH
MOTOR SPATIAL
AWARNESS
WORKING
MEMORY
VISION
SMELL
TASTE HEARING
SPEECH

6. TOUCH
SPATIAL
AWARNESS
WORKING
MEMORY
VISION
HEARING

7. Watching the Brain in Action: Functional Neuroimaging
RESTING TASK
Task Rest Difference
- =
Generating
Verbs
Speaking
Words
Hearing
Words
Seeing
Words
from Posner and Raichle

8. Activation of Occipital (Visual) Cortex in the Blind
Braille Sound Localization Verbal Memory
Sadato, Pascual-Leone et al., Nature: 1996; Brain: Gougoux et al., 2005 PLoS; Nature 2004 Amedi et al. Nat Neurosci 2003; 2004
1998

9. Occipital Visual Cortex: Early vs. Late Blind
EARLY BLIND LATE BLIND
Burton et al., J. Neurophysiol: 2002

10. The Blindfold Experiment: Tactile
Day 5 > Day 1
Blindfold vs Non Blindfold
Pascual-Leone et al., 2003 Merabet et al., PLOS One 2008

11. The Blindfold Experiment: Tactile
Right Hand (reading)
50
40
Braille Character Recognition
30
[% errors]
20
Blindfolded: Training
Non Blindfolded: Training
10
0
Day 1 Day 3 Day 5
Kauffman et al., Neuroreport 2002

12. Braille Alexia Following an Occipital Stroke
Case Report:
- 63 y.o. right-handed female
- blind at birth (retinopathy of pre-maturity)
- Reported VA: No Light Perception OU
- normal milestones, Braille at 6 y.o.
- proficient reader: 120-150 symbols/min
Complaint: light-headedness, difficulty
swallowing, loss of motor coordination, LOC
- admitted to emergency - 24 hr coma
- “normal physical and neurological exam”
- within 24 hrs; alert and interactive
From Hamilton et al., 2000; Neuroreport

13. Transcranial Magnetic Stimulation (TMS): "virtual brain lesions"
Generated
Magnetic Induced
Field Current
TMS Coil
Low frequency (e.g. 1 Hz)
= lowered excitability
High frequency (e.g. 10-20 Hz)
= increased excitability

14. Modulating Braille Reading Performance by Modulating Brain Activity
Low
frequency
Tactile and linguistic manifestations
of "visual" cortex modulation
High
frequency
Roy H. Hamilton and Alvaro Pascual-Leone TICS 1998

15. “Painting is a blind man’s
profession, as blind people have
a clearer vision of reality”
- Picasso
“I wish I had been born blind,
because it would have enhanced
my artistic perception of the
world”
- Monet

16. Esref Armagan
www.armagan.com

17. Drawing vs. Scribbling
Amedi et al., 2008

18. Activation of Occipital (Visual) Cortex in the Blind
Braille Sound Localization Verbal Memory
Sadato, Pascual-Leone et al., Nature: 1996; Gougoux et al., 2005 PLoS; Nature 2004 Amedi et al. Nat Neurosci 2003; 2004
Brain: 1998
Activation of Auditory Cortex in the Deaf
Sign Language Motion Perception Vibro-tactile
+
Nishimura et al., Nature, 1999 Finney et al., Nat Neurosci, 2001 Auer et al., Neuroreport, 2007

19. Helen Keller
Anindya “Bapin”
Bhattacharyya
http://www.bapin.info/index.html

20. Communicating with Bapin:

21. Functional Neuroimaging: ASL (word>non word)
A.B. S.W.
Diffusion Tensor Imaging

22. Wayfinding, Navigation and Cognitive
Mapping

24. target virtual world reconstruction final representation
Jaime Sanchez and Coworkers
C5: University of Chile, Santiago
http://www.c5.cl/audio/pags/softwares/audio_doom/audiodoom_metod.htm

25. stairwell exit
table furniture
door
First Floor monster
First Floor
player
(facing north)
jewel
Second Floor Second Floor

26. Transfer of Navigation Skills Learned with AbES to Real World
Virtual World Real World
Outcome Measures
Quantitative: classroom
10
- time to target
- # of mistakes made path
taken
Qualitative: lobby
-type of errors made entrance
- strategies employed breakdown
statistics of path
-"creativity" and problem solving

27. AbES and Functional Neuroimaging
instructions vs rest
AbES projected auditory
reflecting on a screen
mirror cortex
goal-directed navigation vs rest
parietal
cortex frontal
cortex
subject visual
control keys wearing cortex
headphones
posterior
hippocampus

28. Audio-Haptic Doom and crossmodal interfacing

29. Other Software: University of Chile, Department of Computer Science

30. Artist Bernardo Strozzi (Italian, Genoese, 1581–1644)
Title Tobias Curing His Father's Blindness

31. Case Report: Subject M.M.
- monocular, and at age 3 blinded in fellow
eye from a chemical burn. Undergoes corneal
transplant at childhood; unsuccessful.
- some light perception, no experience of form
or contrast perception. Reports no visual
memories or imagery.
- at 43 y.o., undergoes corneal/limbal stem cell
transplant.
- highly motivated, intelligent individual.
courtesy the Discovery Channel

32. The Retinal Approach
VITREOUS
NFL
GANGLION CELLS
BIPOLAR CELLS
PHOTORECEPTORS
SUB RETINAL
RPE
CHOROID

33. Video courtesy of Second Sight
www.2-sight.com

34. ? ? ?
Cross-modal Adapted
Occipital cortex
Visual
Occipital cortex
maximal visual maximal cross-modal
function adaptation
Factors:
Onset
Duration
Type of Vision Loss
Prior Experience
Rehabilitation Strategy
Merabet et al., 2006

35. correlation between degree of
hypometabolism and success
…Corollaries and Lessons Learned… with a CI. imaging is prognostic
other regressors:
-duration of deafness,
-duration of CI use
Auditory
Cortex *resting hypometabolism and not
cross-modal activation
* pre-lingual deaf children
Nishimura et al., Nature, 1999
Nature
Lee et al., 2001 Nature

36. …Corollaries and Lessons Learned…
Brain Machine Interfaces
www.cyberkineticsinc.com
left (intact) right (amputated)
Ersland et al., NeuroReport 8, 207–210 (1996)

37. TASTE
TOUCH VISION
HEARING SMELL

38. TASTE
TOUCH
HEARING SMELL

39. Jaime Sanchez, PhD
University of Chile
Alvaro Pascual-Leone, MD PhD
Ela Bhatt, PhD
Mark Halko, PhD
Souzana Obretenova
Center for Noninvasive Brain
Stimulation
Joseph Rizzo, MD
Boston Retinal Implant Project
Carroll Center for the Blind
Boston University Center for Biomedical
Imaging
Our patients…