Any Human Heart writing again of a whole-life view: "I don't think there's anything wrong with going back over territory you've previously covered." Though avowedly not an (auto-)biographical novelist, Boyd acknowledged that personal experiences often subconsciously affect a writer's fiction. As in several of Boyd's novels there are parallels with the author's life: both Boyd and Mountstuart lived in Africa and France, studied at Oxford, worked in literary London and had a taste of New York. Boyd usually splits the creation of a novel into two phases: research and writing. The first phase of "Any Human Heart" took 30 months as he carefully
Heart rate predominates as, left unregulated, the SA node would initiate a sinus rhythm of approximately 100 bpm. Both sympathetic and parasympathetic stimuli flow through the paired cardiac plexus near the base of the heart. The cardioaccelerator center also sends additional fibers, forming the cardiac nerves via sympathetic ganglia (the cervical ganglia plus superior thoracic ganglia T1–T4) to both the SA and AV nodes, plus additional fibers to the atria and ventricles. The ventricles are more richly innervated by sympathetic fibers than parasympathetic fibers. Sympathetic stimulation causes the release of the neurotransmitter norepinephrine (also known as noradrenaline) at the neuromuscular junction of