Figure 2.

The crosstalk between the immune system and the brain. Immune molecules cross the blood–brain barrier on occasion of brain damage. They are also expressed during brain development, affecting neurogenesis, neuronal migration, axon guidance, and synapse formation. In the adult brain they modulate activity-dependent refinement of neural circuits and synaptic plasticity (including long-term potentiation, long-term depression, and synaptic scaling), as well as brain function (including cognition). Because chronic changes in the immune molecules levels are observed in neurodevelopmental disorders (particularly autism and schizophrenia), they could also contribute to the neurocognitive profile of affected individuals. Adapted from Garay and McAllister (2010; Figure 3).