Mapping the central neurocircuitry that integrates the cardiovascular response to exercise in humans

Abstract

There are abundant animal data attempting to identify the neural circuitry involved in cardiovascular control. Translating this research into humans has been made possible using functional neurosurgery during which deep brain stimulating electrodes are implanted into various brain nuclei for the treatment of chronic pain and movement disorders. This not only allows stimulation of the human brain, but also presents the opportunity to record neural activity from various brain regions. This symposium review highlights key experiments from the past decade that have endeavoured to identify the neurocircuitry responsible for integrating the cardiovascular response to exercise in humans. Two areas of particular interest are highlighted: the periaqueductal grey and the subthalamic nucleus. Our studies have shown that the periaqueductal grey (particularly the dorsal column) is a key part of the neurocircuitry involved in mediating autonomic changes adapted to ongoing behaviours. Emerging evidence also suggests that the subthalamic nucleus is not only involved in the control of movement, but also in the mediation of cardiovascular responses. Although these sites are unlikely to be the 'command' areas themselves, we have demonstrated that the two nuclei have the properties of being key integrating sites between the feedback signals from exercising muscle and the feedforward signals from higher cortical centres.

Effects of regional brain injury on the newborn autonomic nervous system

“…More recent research in mature animals and human adults has focused on the involvement of higher nervous system structures such as the hypothalamus, basal ganglia, thalami and cortical sites in modulating ANS activity [23]. Direct stimulation and MRI functional testing have highlighted the insular and medial prefrontal cortices as the primary implicated cortical areas [14][15][16][17][18].…”

Metabolic and endocrine response to exercise: sympathoadrenal integration with skeletal muscle

“…A consequence of this neural-hormonal activity also affects cardiovascular function, which is integrated to the delivery of extracellular substrates for the exercising muscle. The importance of neural control of the circulation was presented in a series of papers published where exercise was the primary experimental model and summarised as furthering our understanding of the role and location of central command (Basnayake et al 2012, Matsukawa 2012) expanding the role of muscle afferents (Kaufman 2012) and the effects of neural blockade on the pressor response (Secher & Amann 2012). Owing to the innate potential to increase muscle blood flow by over tenfold from resting muscle conditions, control over blood flow during exercise is essential to avoid compromising central blood volume and pressure (González-Alonso et al 2008).…”

The Neuroprotective Effects of Endurance Training on the Aging Brain

“…Specifically, neuroimaging techniques have enabled investigation into a network of cortical regions associated with the autonomic nervous system and cardiovascular control in conscious humans , Basnayake, Green et al 2012, Macey, Wu et al 2012, Cechetto 2014. These regions include the bilateral IC, ACC, PCC, MPFC, and HC.…”