Week 4- the developing brain

Blueprint analogy of structural development

Each connection is predetermined

Critiques of blueprint analogy

All 86 billion neurones with 10 synapses each cannot all be predetermined

Modern approach to structural development

Each stage (Ie genetics, brain structure) influences the others, and is constantly changing

Prenatal brain development- proliferative zone

Area where glial cells and neurones are made, and migrate away from to target location

Structural features as results of other constraints- cortex

Folded due to amount of neurones in brain

Structural features as results of other constraints- sulci

Pattern due to axon bundle tension

Postnatal development- increase in brain size

Due to synaptogenesis, myelination, glial cell proliferation

Postnatal brain development- plasticity

Experiences cause increased grey matter

Limits of plasticity

Major reorganisation can only occur during set “critical periods”

Critical and sensitive periods explanation- synaptogenesis

Genetically programmed for readying brain to learn, along with genetic stop codon for plasticity to set knowledge in place

Investigating brain development- structural

Simple ulrasound

Visual interest test

Experimenter puts infant in box and hands a stimuli over them, looking for a reflection in the infant’s eyes

Modern preferential looking

Done via screens, babies stay with caregivers, eye tracking done via infrared light

Issues with preferential looking tests

Infants might find both screens 1 and 2 interesting, meaning they CAN discriminate, but the data makes it look like they don’t

Habituation paradigm

Infants enjoy novelty, so if one object remains constant but the other changes, the infant will stop paying attention to the first one and focus on the new toy, showing that they can distinguish between them

Functional neuroscience- ERP N290

Face specific component

Adult equivalent to the N290

N1 or N170

Negative central peak range

300-700m/s

Negative central function

Attention