brain development. the beginning spinal chord and pns

Brain development

The beginning

The beginning

The beginning

Spinal chord and PNS

Spinal chord and PNS

Migration of cells from spinal chord to periphery.

Development of motor neurons

Alignment of sensory and motor neurons (motor & proprioception)

Proper CPG and reflexes require proper development of local circuits

Anterior segments

Hindbrain

MidbrainMesencephalon

DiencephalonTelencephalon

Signaling cascades governCell differentiation & Migration

Eyes

Cortical layers

Glial fibers

Olfactory neurons

From sub-ventricular zone to olfactory bulb

Setting up the connections

Where and when should the axon grow?

Eyes to brain

Setting up topography…

Motor neurons to muscles

Setting up innervation

Cell death

Nerve growth factor

Cells are programed to die unless they get NGF….

Synaptic pruning - PNS

Competition among synapses

Synaptic pruning - CNS

Synaptic pruning - CNS

Occular dominance in a neonate monkey V1

Synaptic pruning is activity dependent

Hebbian learning

Synapses during development

Synaptic plasticity

Map space with inter-aural differences

Synaptic plasticity

Synaptic plasticity

Axonal projections from the Inferior Coliculus to the visual tectum shift.

This shift can only happen in young owls…

Critical periodsA developmental period with enhanced plasticity.

Imprinting

Critical periods

Bird song development

Critical periods

Critical periods

Innervation of primary visual cortex