FIGURE 3.

Spatiotemporal dynamics of the LC-NE system. (A) Anatomical organization of inputs to and outputs of LC. Note, LC-GABA neurons were included in this illustration as potential mechanism for nuancing local LC-NE activity, but, so far, no data exist on the relationship between local LC-GABA and specific LC-NE outputs. (B) Spatial modularity of LC-NE release. Top – Example activity of inputs to LC-NE neurons (orange), LC-NE neurons (blue), and local LC-NE release (purple). Bottom – Local versus global release of NE in output regions is dependent on which LC-NE neurons are activated by a given input. (C) Temporal modularity of LC-NE neuromodulation. Top – activity of local NE release in two given output regions and underlying neuronal activity in each region. Note, we assume that NE release is spatially global for simplicity. We also assume that NE neuromodulation increases neuronal activity in both target regions. Bottom – Due to differential NE receptor expression in brain regions, heterogenous expression of NE receptors on different types of brain cells, or the underlying function of a specific brain region, temporal integration can be local or global.