Figure 2.

Schematic timeline illustrating key neurodevelopmental processes ongoing through gestational and postnatal periods in the mammalian brain. A wide range of prenatal, perinatal, and postnatal insults influence the developing brain both acutely but also chronically, driving an increased propensity for neuronal hyperexcitability and seizure susceptibility during later life. Age-dependent vulnerability to these chronic consequences is thought to be determined, at least in part, by the state of microglial development (changes in number, phenotype, and activity), as well as maturation of neuronal circuits (a product of synaptogenesis and synaptic pruning over time). Adapted from Semple et al. (2013) and Lenz and Nelson (2018).