Figures & data
Figure 1 Overview of vagal circuitry linking the central and peripheral nervous system.
Notes: Visceral afferents converge on the NTS in the brain stem, the first point of integration between the peripheral autonomic nervous system and the central nervous system. Visceral afferents project from the dorsal motor nucleus of the vagus and are key to exerting autonomic control in the periphery.
Abbreviations: NA, nucleus ambiguus; NTS, nucleus tractus solitarii; pBC, preBötzinger complex.
Figure 2 Putative pathways involved in vagus nerve stimulation.
Notes: Stimulation of the vagus activates ascending pathways that alter neural circuits in the brain stem, midbrain, and cortex. Regions that are impacted by vagus nerve stimulation based on past research are included in this diagram.
Abbreviations: NTS, nucleus tractus solitarii; DMX, dorsal motor nucleus of the vagus; LC, locus coeruleus; THAL, thalamus; HypoTHAL, hypothalamus; RTN, retrotrapezoid nucleus; BC, Bötzinger complex; pBC, preBötzinger complex; VRG, ventral respiratory group.
Figure 3 Flow diagram showing the inflammatory neural circuit.
Notes: Inflammatory markers including IL-1b, IL-6, TNFa, IL-10, HMGB1, IL-11, and IL-13 alter peripheral inflammatory tone, which stimulates NFkB, resulting in increased inflammatory signaling to the CNS via the brain stem. This results in output that generates an inflammatory signal. VNS can be used to alter the input/output of this autonomic control circuitry.
Abbreviations: IL, interleukin; TNF, tumor necrosis factor; NFkB, nuclear factor kB; CNS, central nervous system; VNS, vagus nerve stimulation.
