Download Chapter 23

Notes:
Assignment 4 due next Thursday
Will have exam review questions
next week
Class questions
Human Neuropsychology (486 / 686)
Lecture Chapter 23 & 24
.
“Brain Development and
Plasticity”
2
The Development of the Human Brain

Neural Tube

Developmental Abnormalities - Occur due
to genetic program errors, trauma, toxins,
disease
Stages of Brain Development
Neuron Generation
Neural Stem
Cells
- Capacity
for selfrenewal
- produce
progenitor
cells

Cell Migration and
Differentiation
Neural Maturation
Dendrites
Arborization
Spine formation


Axons
Athetosis - http://www.youtube.com/watch?v=gNKKZAfMr8M
Dystonia http://www.youtube.com/watch?v=2O014fPXScU&feature=PlayList&p=5F72
AD603D2AD188&index=0
Synapse Formation and Pruning

Experience expectant
Development depends on the
presence of sensory
experiences

Experience dependent
Generation of synapses
unique to the individual
Glial Development

Myelination
Imaging Studies of Brain Development

Patterns of grey matter
loss


Developmental disorders
Cortical thickness and vocabulary
Development of Problem-Solving Ability
conservation: http://smedia.depaul.edu/lcamras/water.mpg

Growth Spurts in brain during each stage
Environmental Influences on Brain
Organization

Complex
environments
increase brain
size

Behavioral
advantages
Experience: Neural connectivity and
Representational plasticity

Deprivation
- Amblyopia
Enrichment
- increased
representation

Brain Injury and Plasticity

Kennard Principle
Functions are spared when injury occurs early
in development

Effects of brain injury depend on:
Behavior affected
Extent and location of damage
Age at injury
Brain Injury and Plasticity
Effects of damage on
language
Childhood aphasia –
1. Language survives early damage
2. Due to reorganization
3. Right hemisphere damage causes
similar deficits to adults.
Reorganization of Language

Reorganization
depends on area of
damage (left
hemisphere)

Special left
hemisphere
anatomy
Mechanisms of Recovery

The effects of early brain lesions on
behaviors:
1. Complete recovery of function if injury occurs during
neurogenesis
2. Injury during migration and differentiation is devastating
3. After migration and differentiation the brain can recover

Plasticity and recovery:
1. Generation of new neurons
2. Reoganization
3. Generation of new circuitry
Autism Spectrum Disorders
Autism – impaired social interaction, unusual and narrow
interests, language and communication problems, need
for “sameness” without obvious focal cerebral disease

Causes: genetic, viruses

Various brain abnormalities:
Larger head and brain size than normal
Frontal lobe – social interaction
Cerebellum – coordination and habituation
Temporal Lobe - memory
Brainstem – facial abnormalities
Autism Spectrum Disorders

Asperger’s Syndrome
Less severe than autism, have language
Hyperlexia

Savant Syndrome
Narrow range of special abilities
Kim Peek: http://www.youtube.com/watch?v=jL0SthoRMC8
http://video.google.com/videoplay?docid=-6097787318198018019#