The coupling between brain connectivity and heartbeat dynamics unveils the altered interoceptive mechanisms in Parkinson’s disease

Abstract

AbstractParkinson’s disease (PD) is often known for its classical motor symptoms, but non-motor symptoms are often reported including interoceptive and autonomic dysfunctions. Autonomic dysfunctions, such as cardiovascular, urinary, or thermoregulatory abnormalities, are more prone to be associated with motor and cognitive decline, as well as increase the risk of mortality. More recent evidence has shown that Parkinsonian patients may experience alterations in interoceptive processing, i.e., reduced sensitivity to accurately sensing and interpreting internal cues, leading to further impairment in self-awareness, cognitive and emotional processing. Noteworthy, the mechanisms behind these autonomic/interoceptive dysfunctions are not well understood. During the early stages of PD, disruptions in the connectivity of multiple brain regions occur, which has prompted the study of PD as a network-level phenomenon. Our hypothesis is that by examining the relationship between brain connectivity and heartbeat dynamics, we can gain insight into the large-scale network disruptions and the neurophysiology of the disrupted interoceptive mechanisms in PD. Our results show that the coupling of fluctuating alpha and gamma connectivity with heartbeat dynamics is reduced in PD patients, as compared to healthy participants. Furthermore, we show that PD patients under dopamine medication recover part of the brain-heart coupling, in proportion with the reduced motor symptoms. Our proposal offers a promising approach to unveil the physiopathology of PD and promoting the development of new diagnostic methods for the early stages of the disease.