Chapter 3: brain development

Nuerocortex

huge sheet of tissue built from 6 different layers that is folded into the brain; the outer “squishy”A

cell body

contain basic biological material and keeps neuron functioning

dendrites

neural fibers that receive neurotransmitters, the “receiving branches”

axon

neural fibers that conduct signals to other neurons, “firing cannon”

Nervous system development

1. cell production (proliferation)

2. cell migration

3. cell differentiation

4. synapse formation

5. cell death/apoptosis

6. synapse rearrangement

cell migration process

1. spatial layering

2. chemical signaling

3. ride the “gila rail”

spatial layering

new cells push old cells out and migrate to the outside

synapses

connections formed between cells (large number formed in first 2 years)

“use it or lose it”

massive amounts of synapses formed in first 2 years, those that are used survive, those not die (pruning)

experience-expectant plasticity

The brain develops by expecting and integrating common environmental stimuli during critical windows

• birds learn bird song by hearing it from their parents as chicks

brain wiring reasons

• occurs as a result of expected experiences (experience-expectant plasticity)experience-expectant

• also wires differently due to individual experience

vulnerability

times of heightened risk to negative impacts from enviorment

• do not give an infant booze

plasticity

the ability for something to be molded or remodeled

• helps recover from damage

This brain can create it’s own structure

Ex. violin players have 1 more flexible