E14 Neurodevelopment

Title

The development of the nervous system involves sequential processes of neuronal proliferation and death (neurogenesis), cellular migration guided by molecular gradients, initial overproduction of synapses followed by activity-dependent pruning, progressive myelination of axons and temporal windows of especially high plasticity (critical periods). The net neuronal population results from the balance between a logistic proliferation limited by the capacity of the tissue and a rate of programmed cell death. Neuronal migration can be approximated with a reaction-diffusion equation biased by a chemical attractant gradient. Synaptic density follows a pattern of overproduction followed by pruning dependent on the correlation of pre- and postsynaptic activity, in a rule formally related to the plasticity of E07 but aimed at eliminating poorly correlated synapses. Myelination is modeled as a sigmoidal growth curve with age, and the window of critical plasticity as a bell-shaped temporal profile centered on a peak age.

ID:4272