Notes:

Assignment 4 due next Thursday

Will have exam review questions next week

Class questions

2222

““Brain Development and Brain Development and PlasticityPlasticity””

Human Neuropsychology (486 / 686)Human Neuropsychology (486 / 686)

Lecture Chapter 23 & 24Lecture Chapter 23 & 24

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The Development of the Human BrainThe Development of the Human Brain

Neural TubeNeural Tube

Developmental Abnormalities - Occur due Developmental Abnormalities - Occur due to genetic program errors, trauma, toxins, to genetic program errors, trauma, toxins, diseasedisease

Stages of Brain DevelopmentStages of Brain Development

Neuron GenerationNeuron Generation

Neural Stem Neural Stem CellsCells

- Capacity - Capacity for self-for self-renewalrenewal

- produce - produce progenitor progenitor cellscells

Cell Migration and Cell Migration and DifferentiationDifferentiation

Neural MaturationNeural Maturation DendritesDendritesArborizationArborizationSpine formationSpine formation

AxonsAxons

AthetosisAthetosis - - http://www.youtube.com/watch?v=gNKKZAfMr8Mhttp://www.youtube.com/watch?v=gNKKZAfMr8M

Dystonia Dystonia - - http://www.youtube.com/watch?http://www.youtube.com/watch?v=2O014fPXScU&feature=PlayList&p=5F72AD603D2AD188&index=0v=2O014fPXScU&feature=PlayList&p=5F72AD603D2AD188&index=0

Synapse Formation and PruningSynapse Formation and Pruning

Experience expectantExperience expectantDevelopment depends on the Development depends on the

presence of sensory presence of sensory experiencesexperiences

Experience dependentExperience dependent Generation of synapses Generation of synapses

unique to the individualunique to the individual

Glial DevelopmentGlial Development

MyelinationMyelination

Imaging Studies of Brain DevelopmentImaging Studies of Brain Development Patterns of grey matter lossPatterns of grey matter loss

Cortical thickness and vocabularyCortical thickness and vocabulary

Developmental disorders Developmental disorders

Development of Problem-Solving AbilityDevelopment of Problem-Solving Ability

conservation: conservation: http://smedia.depaul.edu/lcamras/water.mpg http://smedia.depaul.edu/lcamras/water.mpg

Growth Spurts in brain during each stageGrowth Spurts in brain during each stage

Environmental Influences on Brain Environmental Influences on Brain OrganizationOrganization

Complex Complex environments environments increase brain increase brain sizesize

Behavioral Behavioral advantagesadvantages

Experience: Neural connectivity and Experience: Neural connectivity and Representational plasticityRepresentational plasticity

DeprivationDeprivation

- Amblyopia- AmblyopiaEnrichmentEnrichment

- increased - increased representationrepresentation

Brain Injury and PlasticityBrain Injury and Plasticity

Kennard PrincipleKennard PrincipleFunctions are spared when injury occurs early Functions are spared when injury occurs early

in developmentin developmentEffects of brain injury depend on: Effects of brain injury depend on:

Behavior affectedBehavior affected

Extent and location of damageExtent and location of damage

Age at injuryAge at injury

Brain Injury and PlasticityBrain Injury and Plasticity

Effects of damage on Effects of damage on languagelanguage

Childhood aphasia – Childhood aphasia –

1. Language survives early damage1. Language survives early damage

2. Due to reorganization 2. Due to reorganization

3. Right hemisphere damage causes3. Right hemisphere damage causes

similar deficits to adults.similar deficits to adults.

Reorganization of LanguageReorganization of Language

Reorganization Reorganization depends on area of depends on area of damage (left damage (left hemisphere)hemisphere)

Special left Special left hemisphere hemisphere anatomyanatomy

Mechanisms of RecoveryMechanisms of Recovery

The effects of early brain lesions on The effects of early brain lesions on behaviors:behaviors:1. Complete recovery of function if injury occurs during 1. Complete recovery of function if injury occurs during

neurogenesisneurogenesis

2. Injury during migration and differentiation is devastating 2. Injury during migration and differentiation is devastating

3. After migration and differentiation the brain can recover3. After migration and differentiation the brain can recover

Plasticity and recovery:Plasticity and recovery:1. Generation of new neurons 1. Generation of new neurons

2. Reoganization 2. Reoganization

3. Generation of new circuitry3. Generation of new circuitry

Autism Spectrum DisordersAutism Spectrum Disorders

Autism – Autism – impaired social interaction, unusual and narrow impaired social interaction, unusual and narrow interests, language and communication problems, need for interests, language and communication problems, need for “sameness” without obvious focal cerebral disease“sameness” without obvious focal cerebral disease

Causes: genetic, virusesCauses: genetic, viruses

Various brain abnormalities:Various brain abnormalities:Larger head and brain size than normalLarger head and brain size than normalFrontal lobe – social interactionFrontal lobe – social interactionCerebellum – coordination and habituationCerebellum – coordination and habituationTemporal Lobe - memoryTemporal Lobe - memoryBrainstem – facial abnormalitiesBrainstem – facial abnormalities

Autism Spectrum DisordersAutism Spectrum Disorders

Asperger’s SyndromeAsperger’s SyndromeLess severe than autism, have languageLess severe than autism, have language

HyperlexiaHyperlexia

Savant SyndromeSavant SyndromeNarrow range of special abilities Narrow range of special abilities Kim Peek: http://www.youtube.com/watch?v=jL0SthoRMC8Kim Peek: http://www.youtube.com/watch?v=jL0SthoRMC8

http://video.google.com/videoplay?docid=-http://video.google.com/videoplay?docid=-6097787318198018019#6097787318198018019#