modification of brain circuits as a result of experience...
TRANSCRIPT
![Page 1: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/1.jpg)
Modification of Brain Circuits as a Result of Experience – Chapter 24, Purves et al. 4th Ed.
Pre-natal construction of neural circuits (the “highways” are genetically specified):
(1/6/2010) – Mona Buhusi
Postnatal modification of neural circuits (e.g., learn a language):
Adapt to changing external environments, changes in head & brain size
Temporal windows for the brain to become refractory to the lessons of experience – critical or sensitive periods, e.g. learning a new language
Neural activity triggers the refinement of connections via calcium, neurotrophins, local gene expression, cytoskeleton
![Page 2: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/2.jpg)
Postnatal Experience =
patterns of neural activity
![Page 3: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/3.jpg)
System, circuit, or cell waiting for specific instructional information from the environment in order to continue to develop…
… If “appropriate” experience is not gained during the critical period, the pathway may never attain the ability to process certain forms of information, e.g. depth, and perception may be impaired permanently.”
During a critical period, the system can adapt to virtually any stimuli, appropriate or inappropriate.
It is possible to delay/accelerate the critical period, e.g. environment – dark rearing; molecules – GABA
Idea of a critical period
![Page 4: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/4.jpg)
Box 24A Built-In Behaviors: Experience is an ON switch
Goslings forever follow the first large moving object they hear and see during their first day of life.
This imprinting is irreversible.
Vision and audition are very poorly developed in newborn mammals – rely more on olfaction.
Olfaction – more evolutionary primitive…
![Page 5: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/5.jpg)
1) Duration is proportional to lifespan
2) Functional competition between inputs (e.g., left vs. right eye)
3) Neuronal activity (action potentials, forward and back propagating)
4) Structural consolidation of pathways
5) Onset and duration is defined by neural activity
6) Different critical periods for different systems: e.g., direction selectivity and ocular dominance are plastic at
different times
6) Diversity of sensory/motor systems & molecular mechanisms
7) Particular roles of excitation and inhibition – GABA can open the critical period
8) Potential for reactivation? (training, growth factors)
Autism, Schizophrenia: critical period disorders?
Properties of critical periods
![Page 6: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/6.jpg)
Figure 24.1 Manual “babbling” of hands in deaf versus hearing infants
(Pre
curs
ors f
or si
gn-la
ngua
ge)
![Page 7: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/7.jpg)
Figure 24.2 Learning language
![Page 8: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/8.jpg)
Box 24B Birdsong
Listen to adult male tutor 10-20 times
Successful courtship depends on early auditory and vocal experience
![Page 9: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/9.jpg)
• Lyre bird - Australia
http://www.youtube.com/watch?v=VjE0Kdfos4Y
![Page 10: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/10.jpg)
Use it or lose it or more sophisticated?
![Page 11: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/11.jpg)
![Page 12: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/12.jpg)
Visual system:
Much clearer understanding of how changes in connectivity contribute to critical periods:
Infinite control and reproducibility of visual stimuli in space and time.
Visual cortex (not retina or thalamus) is especially plastic.
![Page 13: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/13.jpg)
Figure 12.8 Neurons in the primary visual cortex respond selectively to oriented edges
![Page 14: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/14.jpg)
Contrast invariance of orientation tuning
![Page 15: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/15.jpg)
Figure 12.11 The basis of functional maps in primary visual cortex (Part 1)
![Page 16: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/16.jpg)
Figure 12.11 The basis of functional maps in primary visual cortex (Part 2)
![Page 17: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/17.jpg)
Figure 12.12 Functional imaging techniques reveal the orderly mapping of orientation preference in primary visual cortex
![Page 18: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/18.jpg)
Anatomy and physiology of ocular dominance plasticity
![Page 19: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/19.jpg)
Axons from cells in the lateral geniculate nucleus (LGN) serving each eye terminate in separate bands in layer 4 called “ocular dominance columns”.
Ocular dominance maps superimposed on orientation maps – spatial scales are different
Visual cortex
Layer 4
Layer 2/3
![Page 20: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/20.jpg)
Figure 12.13 Mixing of the pathways from the two eyes first occurs in the striate cortex
Human visual cortex: Ocular dominance columns
![Page 21: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/21.jpg)
Box 24C Transneuronal Labeling in animals using Radioactive Amino Acids
Could be problematic in early development if …?
![Page 22: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/22.jpg)
Figure 24.3 Ocular dominance columns in the primary visual cortex of an adult macaque monkey
Technique could be problematic in early development if …?
![Page 23: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/23.jpg)
How can one label ocular dominance columns in the human brain?
![Page 24: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/24.jpg)
Autoradiographic montage showing the ocular dominance columns in layer 4c of the left striate cortex of a macaque labeled by injection of radioactive proline into the left eye.
![Page 25: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/25.jpg)
Cytochrome Oxidase (CO) montage prepared from alternate sections showing the ocular dominance columns revealed by enucleation of the right eye. CO and [3H]proline are identical.
Cytochrome Oxidase – mitochondrial (metabolic) enzyme
![Page 26: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/26.jpg)
Human
3,477 mm2
Macaque
1,127 mm2
![Page 27: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/27.jpg)
Right occipital lobe from a 79-year-old man blind for one year in his left eye.
![Page 28: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/28.jpg)
Half-way through dissection process
Human visual cortex continued
![Page 29: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/29.jpg)
Complete flatmount prior to microtoming
Human visual cortex continued
![Page 30: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/30.jpg)
Complete Pattern of Human Ocular Dominance Columns
Human visual cortex continued
![Page 31: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/31.jpg)
Columns after applying a Fourier filter and a threshold function
Human visual cortex continued
![Page 32: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/32.jpg)
Human visual cortex continued – fMRI of ocular dominance columns
![Page 33: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/33.jpg)
Development of Ocular Dominance Columns, as identified by transneuronal labeling
Do LGN inputs in visual cortex normally undergo developmental segregation…?
LeVay, Stryker, Shatz, 1978
Ocular dominance columns in cat visual cortex
Could be problematic in early development if …?
![Page 34: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/34.jpg)
Figure 24.6 Effect of monocular deprivation on ocular dominance columns in the macaque monkey
Normal Monocularly deprived after birth
Deprived eye columns are shrunken, not disappeared. So not disuse mediated withering away but competitive imbalance
![Page 35: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/35.jpg)
• We are born with ocular dominance columns but abnormal experience can modify them.
• Depth (stereo) vision develops 4-6 months after birth in humans.
![Page 36: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/36.jpg)
Figure 24.7 Effect of monocular deprivation on terminal arborizations of lateral geniculate nucleus axons in the visual cortex – Cat area 17
(1 week)
![Page 37: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/37.jpg)
Effect of monocular deprivation on terminal arborizations of lateral geniculate nucleus axons in the visual cortex – Cat area 18
Potential for recovery?
![Page 38: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/38.jpg)
Physiology of ocular dominance: Record the response to left vs. right eye stimulation independently
![Page 39: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/39.jpg)
Figure 24.4 Effect of monocular deprivation on ocular dominance in kittens v. adult cats (Part 1)
![Page 40: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/40.jpg)
Figure 24.4 Effect of monocular deprivation on ocular dominance in kittens v. adult cats (Part 2)
Disuse or Competition?
Deprived eye disconnected?
![Page 41: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/41.jpg)
Figure 24.5 Effect of short period of monocular deprivation at height of critical period in cat
Disuse or Competition?
(need to do another exp – binocular deprivation)
Deprived eye disconnected?
Hubel & Wiesel’s work directly impacted how human babies are treated after monocular eye injuries or if they are born with a cataract
![Page 42: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/42.jpg)
Figure 24.9 Ocular dominance in adult cats in which strabismus was induced during critical period
Hubel & Wiesel’s work directly impacted how human babies born with squint are treated
Overall activity is the same for both eyes, but correlation from corresponding retinal points is different
![Page 43: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/43.jpg)
Figure 24.4 Effect of monocular deprivation on ocular dominance in kittens v. adult cats (Part 3)
Binocular deprivation: Disuse does not induce ocular dominance plasticity.
Competition and local correlations in neural activity (spikes) are the drivers of plasticity
![Page 44: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/44.jpg)
Figure 24.8 How Hebb’s postulate might operate during development of the visual system
cooperate
compete
Post- matches Pre-
![Page 45: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/45.jpg)
Box 24D Correlation as Causation: Lessons from a Three-Eyed Frog
“Gain of function”
![Page 46: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/46.jpg)
Figure 24.10 Transduction of electrical activity into cellular change via Ca2+ signaling
Change dendrite/ spine structure
![Page 47: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/47.jpg)
![Page 48: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/48.jpg)
Molyneux's problem is an unsolved problem in philosophy for more than three centuries:
“If a man born blind can feel the differences between shapes such as spheres and cubes, could he similarly distinguish those objects by sight if given the ability to see?”
Can one begin to have sight late in life, past the critical period? If so, can such subjects provide insight into how we learn to see?
One in 100 children in India is blind, largely from congenital cataracts that go untreated. In the US & Europe, cataracts are an disease of the elderly. Limited care due to cost and limited hope due to “apparent” dogmas.
![Page 49: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/49.jpg)
What if a “blind” adolescent or adult (born with congenital cataract) receives surgery (as adolescents or adults), what would they see?
Note that a congenital cataract does result in some form vision and motion sensitivity intact, its just that acuity is gone.
Initially in these patients that receive new lenses, there are integrative difficulties – meaning that they see fragmented pieces rather than whole/singular objects (like autism).
But motion cues can help parse objects from background or one overlapping object from another. After a few weeks or months of experience, motion is no longer required to parse objects.
Motion cues and thus motion-sensitive neurons in the primary visual cortex is a likely bootstrap for visual learning and developing integrative skills.
![Page 50: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/50.jpg)
![Page 51: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/51.jpg)
![Page 52: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/52.jpg)
![Page 53: Modification of Brain Circuits as a Result of Experience ...people.musc.edu/~woodward/Modification.pdf · Modification of Brain Circuits as a Result of Experience – Chapter 24,](https://reader033.vdocument.in/reader033/viewer/2022053101/60616cc839e43f14ae2dbb56/html5/thumbnails/53.jpg)
Does the recovery of object recognition in “lens blind” subjects challenge Hubel & Wiesel’s findings on ocular dominance plasticity?