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2 Plasticity Lecture 5
3 Food for thought What does it mean that the brain is “plastic”Are there “critical periods”? How important are they? Are there parts of the brain that are predestined for some behavior? Think about the neurobiology of brain development and how that might contribute to plasticity.
4 Types of plasticity Experience independent
5 Types of plasticity Experience independent Experience dependent
6 Types of plasticity Experience independent Experience dependentExperience expectant
7 Experience Independent PlasticityExperience is not required to “wire” up the system
8 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species
9 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species Examples?
10 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species Examples? Brainstem
11 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species Examples? Brainstem Some aspects of the visual system
12 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species Examples? Brainstem Some aspects of the visual system Mechanism
13 Experience Independent PlasticityExperience is not required to “wire” up the system Systems that are similar across species Examples? Brainstem Some aspects of the visual system Mechanism Gene expression
14 Experience Dependent PlasticitySpecific to experience
15 Experience Dependent PlasticitySpecific to experience Different by individual
16 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience
17 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples?
18 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples? Memory
19 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples? Memory Stressful life events?
20 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples? Memory Stressful life events? Formation of new connections?
21 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples? Memory Stressful life events? Formation of new connections? Mechanism
22 Experience Dependent PlasticitySpecific to experience Different by individual Based upon individual experience Examples? Memory Stressful life events? Formation of new connections? Mechanism Likely LTP or similar mechanism
23 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system.
24 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system. Most members of the species have that experience
25 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system. Most members of the species have that experience Examples? Language
26 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system. Most members of the species have that experience Examples? Language Ocular Dominance Columns
27 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system. Most members of the species have that experience Examples? Language Ocular Dominance Columns Mechanism
28 Experience Expectant PlasticityA particular experience that is expected in the environment contributes to wiring of system. Most members of the species have that experience Examples? Language Ocular Dominance Columns Mechanism Redundant connections in the brain
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32 Transplantation StudiesTaking visual cortex and moving it to auditory cortex
33 Transplantation StudiesTaking visual cortex and moving it to auditory cortex Takes on some characteristics of auditory (e.g., responds to sound)
34 Transplantation StudiesTaking visual cortex and moving it to auditory cortex Takes on some characteristics of auditory (e.g., responds to sound) Takes on other characteristics of visual (e.g., the way cells are organized).
35 Transplantation StudiesTaking visual cortex and moving it to auditory cortex Takes on some characteristics of auditory (e.g., responds to sound) Takes on other characteristics of visual (e.g., the way cells are organized). Mechanism
36 Transplantation StudiesTaking visual cortex and moving it to auditory cortex Takes on some characteristics of auditory (e.g., responds to sound) Takes on other characteristics of visual (e.g., the way cells are organized). Mechanism Redundant connections maintained or reformed when cortex is moved.
37 Recovery from early lesionsExamples
38 Recovery from early lesionsExamples Language and the left hemisphere
39 Recovery from early lesionsExamples Language and the left hemisphere Spatial abilities and the right hemisphere
40 Recovery from early lesionsExamples Language and the left hemisphere Spatial abilities and the right hemisphere Mechanism
41 Recovery from early lesionsExamples Language and the left hemisphere Spatial abilities and the right hemisphere Mechanism Redundant connections
42 Mechanism for Recovery from lesion: Example
43 Mechanism for Recovery from lesion: Example
44 Negative experience Children raised in impoverished environments (e.g., orphanages)
45 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size?
46 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow?
47 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow? Animal analogues – Rearing studies
48 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow? Animal analogues – Rearing studies Effects on brain
49 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow? Animal analogues – Rearing studies Effects on brain Effects on behavior
50 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow? Animal analogues – Rearing studies Effects on brain Effects on behavior Abused children
51 Negative experience Children raised in impoverished environments (e.g., orphanages) Reduced brain size? Reduced blood flow? Animal analogues – Rearing studies Effects on brain Effects on behavior Abused children Responses to emotional expressions
52 Experiments of Nature People born deaf
53 Experiments of Nature People born deaf What happens?
54 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs”
55 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs” Auditory areas may be “taken over” for visual function
56 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs” Auditory areas may be “taken over” for visual function Improved attention to movement in the periphery
57 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs” Auditory areas may be “taken over” for visual function Improved attention to movement in the periphery Specific to deafness: Not sign language
58 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs” Auditory areas may be “taken over” for visual function Improved attention to movement in the periphery Specific to deafness: Not sign language Language is visual-spatial, but still in the left hemisphere
59 Experiments of Nature People born deaf What happens?Visual areas increase in size and “jobs” Auditory areas may be “taken over” for visual function Improved attention to movement in the periphery Specific to deafness: Not sign language Language is visual-spatial, but still in the left hemisphere (for anyone who learns a visual/spatial language).
60 Plasticity in adulthoodExperience Dependent plasticity
61 Plasticity in adulthoodExperience Dependent plasticity Rats in enriched environments have more cortical connections
62 Plasticity in adulthoodExperience Dependent plasticity Rats in enriched environments have more cortical connections Can be rearing
63 Plasticity in adulthoodExperience Dependent plasticity Rats in enriched environments have more cortical connections Can be rearing But also occurs in aged rats
64 Plasticity in adulthoodExperience Dependent plasticity Rats in enriched environments have more cortical connections Can be rearing But also occurs in aged rats ED Plasticity can occur throughout the lifespan
65 Plasticity in adulthoodExperience Dependent plasticity Rats in enriched environments have more cortical connections Can be rearing But also occurs in aged rats ED Plasticity can occur throughout the lifespan String Instrument players
66 Plasticity in adulthoodChange in cortical representation due to amputation
67 Plasticity in adulthoodChange in cortical representation due to amputation Mechanism
68 Plasticity in adulthoodChange in cortical representation due to amputation Mechanism Formation of new connections?
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