Color-In Comics: Neurons at Play

Microglia act as immune effector cells in the brain in response to injury or disease, and also help ensure proper neuronal function in healthy conditions. To this end, they are masters of surveillance and rapid response. They engulf cell debris, regulate the number of neurons in the brain during development and in adulthood, and help establish correct wiring of neuronal synapses.

Microglia can strip neurons of synapses to break incorrectly wired connections, and promote maturation of correct synaptic connections. The majority of this happens during development, when there are too many neurons and too many connections. But this can also be important in adulthood during events of synaptic plasticity, when connections between neurons are remodeled in response to learning.