Measures of CNS-Autonomic Interaction and Responsiveness in Disorder of Consciousness

Abstract

Neuroimaging studies have demonstrated functional interactions between autonomic (ANS) and brain (CNS) structures involved in higher brain functions, including attention and conscious processes. These interactions have been described by the Central Autonomic Network (CAN), a concept model based on the brain-heart two-way integrated interaction. Heart rate variability (HRV) measures proved reliable as non-invasive descriptors of the ANS-CNS function setup and are thought to reflect higher brain functions. Autonomic function, ANS-mediated responsiveness and the ANS-CNS interaction qualify as possible independent indicators for clinical functional assessment and prognosis in Disorders of Consciousness (DoC). HRV has proved helpful to investigate residual responsiveness in DoC and predict clinical recovery. Variability due to internal (e.g., homeostatic and circadian processes) and environmental factors remains a key independent variable and systematic research with this regard is warranted. The interest in bidirectional ANS-CNS interactions in a variety of physiopathological conditions is growing, however, these interactions have not been extensively investigated in DoC. In this brief review we illustrate the potentiality of brain-heart investigation by means of HRV analysis in assessing patients with DoC. The authors’ opinion is that this easy, inexpensive and non-invasive approach may provide useful information in the clinical assessment of this challenging patient population.

Impact of Altered Breathing Patterns on Interaction of EEG and Heart Rate Variability

“…Various neuroimaging studies establishing functional interaction between autonomic nervous system (ANS) and cortical processes involved in consciousness and attention has supported the central autonomic network model for explaining ANS–CNS (central nervous system) interaction. 1 – 4 This interaction forms the basis for the dynamic nature of homeostatic processes against the physiological or pathological challenges to the body. 5 In this context, heart rate variability (HRV), reflecting the alteration in RR intervals over time, is being used widely for studying the functional link between cardiovascular system and CNS.…”

Impact of acute stress on cortical electrical activity and cardiac autonomic coupling

“…At the same time, others have also suggested such activity will likely trigger emotive cognitions. Hence a cognitive task that elicits prefrontal delta activity is likely also associated with acute stress response and deeper thalamocortical and brainstem regions that can control cardiac autonomic responses (Riganello et al, 2019). In summary, delta activity, as recorded in prefrontal areas, is well described and increases during different complex cognitive processes that can be stressful (Massimini et al, 2000).…”

Birth weight and heart rate autonomic recovery following exercise in healthy term-born adults

“…With the purpose of governing potential sources of bias, all procedures were performed in a noiseless room with temperature between 21 °C and 25 °C, humidity between 40 and 60% and between 17:00 and 22:00 to standardize and avoid circadian influences 22 . The subjects were instructed to avoid drinking alcohol or caffeinated drinks and to not perform exhaustive exercise 24 h before the protocols.…”