Figure 2.

Distinct neuroimmune states. Each state is a unique snapshot of behavior, immune signaling, cellular changes, active cytokine networks and epigenetic signature at that time. Early- and late- acute immune states are distinguished by activation of different cytokine networks (represented by ball-and-stick figures); microglia show activated morphologies only during acute and chronic activation states; persistent changes are indistinguishable from naïve baseline in the absence of additional stimulation. Learning and memory may also be considered distinct neuroimmune (and epigenetic) states. Figure adapted from Waddington (1957).