ACC	anterior part of the cingulate gyrus cortex
Ach	acetylcholine
AD	Anno Domini
AF	atrial fibrillation
AN	afferent (sensory) neurons
ANS	autonomic nervous system
ARIs	acute respiratory infections
AV	atrioventricular
AVP	arginine-vasopressin
BC	before Christ
BP	blood pressure
BPD	breathing pattern disorder
CeA	central nucleus of the amygdale
ChAT	choline acetyltransferase
CGRP	calcitonin gene-related peptide
COVID-19	coronavirus disease 2019
DMH	dorsomedial nucleus
DMV	dorsal motor nucleus of the vagus
DVC	dorsal vagal complex
ENS	enteric nervous system
EPN	efferent parasympathetic neurones
ESN	efferent sensory neurons
GABA	gamma-aminobutyric acid
HR	heart rate
HRV	HR variability
IC	cortex of insula
ICNS	intracardiac nervous system
IML	intermediolateral
IN	interneurons
IR	immunoreactivity
LQTS	long QT syndrome
ME/CFS	myalgic encephalomyelitis/chronic fatigue syndrome
MRI	magnetic resonance imaging
NA	noradrenaline
NAmb	nucleus ambiguous
Nav1.5	voltage-gated Na+ channels
NANC	non-adrenergic non-cholinergic
NFs	nerve fibers
NG	nodose ganglion
nNOS	neuronal nitric oxide synthase
NO	nitric oxide
NPY	neuropeptide Y
NTS	nucleus of the solitary tract
NS	neuronal somata
PAG	periaqueductal gray matter
PASC	post-acute sequelae of SARS-CoV-2 infection
PBN	parabrachial nucleus
PG	petrose ganglion
POT	postural orthostatic tachycardia syndrome
PVN	paraventricular nucleus
PVT	polyvagal theory
QTc	corrected QT interval
REM	rapid eye movement
RSA	respiratory sinus arrhythmia
RVLM	rostral ventrolateral medulla
RYR2	ryanodine receptor 2
SA	sinoatrial
SARS-CoV-2	Severe Acute Respiratory Syndrome Coronavirus 2
SERCA	sarcoendoplasmic reticulum Ca2+-ATPase
SIDS	sudden infant death syndrome
SIF	small, intensely fluorescent cells
SN	sympathoexcitatory neurons
SPN	sympathetic preganglionic neurons
Sub P	substance P
SUDEP	sudden unexpected death in epilepsy
TH	tyrosine hydroxylase
VIP	vasoactive intestinal peptide
VPN	vagal (parasympathetic) preganglionic neurons
VVC	ventral vagal complex