Central autonomic network functional connectivity: correlation with baroreflex function and cardiovascular...

Area of Science:

• Neuroscience
• Cardiovascular Physiology
• Gerontology

Background:

• The baroreflex is vital for short-term cardiovascular regulation through the autonomic nervous system.
• While central autonomic system contributions to baroreflex regulation are known in young adults, they remain understudied in older adults.

Purpose of the Study:

• To investigate the association between central autonomic network (CAN) connectivity and baroreflex sensitivity (BRS) in healthy older adults at rest.
• To explore the role of specific brain regions within the CAN in peripheral cardiac autonomic regulation in aging.

Main Methods:

• Functional magnetic resonance imaging (fMRI) to assess resting-state brain functional connectivity (FC) of the CAN.
• Baroreflex sensitivity (BRS) assessment using modified Oxford and transfer function methods.
• Analysis of associations between FC in specific brain regions and BRS and heart rate variability (HRR) metrics.

Main Results:

• FC between the left amygdala and left medial frontal gyrus (MeFG) correlated with BRS and low-frequency (LF) R-R interval (RRI) variability.
• Connectivity of the right amygdala showed associations with BRS in the anterior cingulate cortex (ACC) and RRI variability in the left occipital region.
• Left insula sub-region connectivity confirmed the link between CAN and BRS.

Conclusions:

• The central autonomic network, potentially with left-lateralized involvement, plays a role in peripheral cardiac autonomic regulation at rest in older adults.
• Brain neural network function is important for maintaining cardiovascular homeostasis in the aging population.