The Sickening Mind: Brain, Behaviour, Immunity and Disease. Paul Martin

(Astolat, by the way, is Guildford and the maiden’s name is Elaine. Fortunately, ‘The Fair Maiden of Astolat’ has more Arthurian resonance than ‘Elaine of Guildford’.)

      Sir Launcelot is grievously wounded and the Fair Maiden goes to look after him. Night and day she tends him, until his wounds are healed and Sir Launcelot is ready to take his leave. The Fair Maiden of Astolat beseeches Sir Launcelot to marry her or, failing that, at least go to bed with her. But the upstanding knight will not countenance marriage and refuses to dishonour the Fair Maiden by indulging in extramarital frolicking. She begs him again to be her husband or her lover, but to no avail. ‘“Alas,” said she, “then must I die for your love.”’ The noble knight leaves Astolat to get back to some real man’s work (fighting), leaving the emotionally wrecked Fair Maiden of Astolat behind him. Her mental state and self-destructive behaviour soon wreak havoc upon her physical health:

      Now speak we of the Fair Maiden of Astolat that made such sorrow day and night that she never slept, ate, nor drank … So when she had thus endured a ten days, that she feebled so that she must needs pass out of this world, then she shrived her clean, and received her Creator … ‘it is the sufferance of God that I shall die for the love of so noble a knight … I loved this noble knight, Sir Launcelot, out of measure, and of myself, good Lord, I might not withstand the fervent love wherefore I have my death.’

      True words from the Fair Maiden of Astolat, because very soon she dies. Clutched in her hand is a letter proclaiming her love for Sir Launcelot. That love has sent the Fair Maiden to her death, a death achieved through her behaviour.

      Reckless behaviour allied with emotional distress can destroy an individual’s physical health, as illustrated in Jude the Obscure, Thomas Hardy’s novel about ‘a deadly war waged between flesh and spirit’.

      Jude Fawley, a self-educated young man of lowly origins, aspires to leave his unlovely country village and enter the hallowed portals of Christminster (Oxford) University. But the restrictions imposed upon Jude by class and poverty mean that he must instead make his way as a humble stonemason. Jude’s romantic life is as frustrating and unsuccessful as his academic life. After being trapped into an ill-fated marriage to a pig-breeder’s daughter he falls in love with his cousin Sue. The two are drawn together by an almost mystical affinity, but Sue leaves him to marry an older man. The two lovers are eventually united and live together, unmarried and condemned by society, in poverty and unhappiness. In the end Jude loses Sue, who returns to her husband.

      Having failed to fulfil both his intellectual and romantic desires, Jude goes into physical and mental decline. Like many a nineteenth-century tragic hero, he succumbs to a consumptive illness which proves to be terminal. Jude’s behaviour exacerbates his medical condition. With careless disregard for his health he makes a long journey on foot in the pouring rain to see Sue for the last time. She rejects his pleas and he returns to Christminster, physically and emotionally broken. But, as Jude explains to his former wife, he was fully aware of the risk to his health when he undertook the journey:

      I made up my mind that a man confined to his room by inflammation of the lungs, a fellow who had only two wishes left in the world, to see a particular woman, and then to die, could neatly accomplish those two wishes at one stroke by taking this journey in the rain. That I’ve done. I have seen her for the last time, and I’ve finished myself – put an end to a feverish life which ought never to have begun!

      Eventually he dies, alone and neglected, not yet thirty years old. Hardy implicitly takes a multi-causal view of Jude’s final illness, since environmental and constitutional factors play a role in it, together with psychological stress.⁴ His emotional distress at losing Sue and at the death of their children acted as a trigger, but the illness also has antecedents in Jude’s weak constitution and the harsh conditions he endured during his time as a stonemason:

      I was never really stout enough for the stone trade, particularly the fixing. Moving the blocks always used to strain me, and standing the trying draughts in buildings before the windows are in, always gave me colds, and I think that began the mischief inside.

      Most of us die sooner than we have to because of the way we behave and the choices we make. Personally, though, I have some sympathy with Publilius Syrus, who two thousand years ago expressed the opinion that: ‘They live ill who expect to live always.’

      

Mind over immune matter

      In this struggle Tarrou’s robust shoulders and chest were not his greatest assets; rather, the blood which had oozed under Rieux’s needle and, in this blood, that something more vital than the soul, which no human skill can bring to light.

      Albert Camus, The Plague (1947)

      We turn now to a less visible, but no less important, mechanism by which the mind and body interact to affect health: the immune system. Among the most important developments in recent years has been the discovery of numerous biological pathways connecting the brain with the body’s defence and regulatory mechanisms. Through these pathways the biological system that underlies our thoughts, emotions and behaviour – the brain – can exert a pervasive influence on the biological system that defends the body against most forms of disease – the immune system.

      Our physical health depends critically on how well our immune system is functioning. One reason why a person suffering from psychological stress is more susceptible to colds and infections is because their immune system is less able to resist when they are exposed to disease-causing viruses or bacteria. In the following chapters we shall be exploring the manifold ways in which the mind and immune system affect each other. But before we do this we need to clarify a few basic issues.

      So far I have referred rather sweepingly to the mind’s effect on the immune system, as though the immune system were a homogeneous entity whose activities could be measured in a simple way, like temperature or blood pressure. In reality, the immune system is a breathtakingly complex and subtle entity whose intricate workings are still far from being fully understood. Immunology is one of the branches of science that has made the most spectacular leaps in understanding over the past thirty years, but it still has a very long way to go. To unravel how the mind influences physical health we must first establish what the immune system does and how it works.

UNDERSTANDING IMMUNITY

      The immune system is one of the great wonders of nature, rivalled only by the brain in its intricacy and elegance of design. It is a multi-layered system of biological defences whose primary purpose is to defend the body from bacteria, viruses, fungi, parasites, toxins, cancerous cells and other disease-causing agents. The immune system is indeed a system, in the strict sense of the word: a highly complex and co-ordinated array of interrelated, interacting elements.

      Like the economy of a nation, the immune system is not located exclusively in one place. In fact, the cells of the immune system are spread out all over the body. The majority are located in those organs whose purpose often seems slightly mysterious to the layperson: the thymus (located at the base of the neck); the spleen (below and behind the stomach); the lymph nodes (clumps of tissue in the armpit, groin, behind the ears and elsewhere); the bone marrow; the tonsils; and obscure backwaters of the gut (Peyer’s patches and the appendix).

      Immune cells are also to be found in the blood. These are the white blood cells (or leucocytes). Immune cells are carried in the bloodstream to locations in the body where they are needed, particularly sites of injury or infection. When an area of tissue is injured or infected an inflammatory response is triggered: the blood vessels swell up and become more permeable, thus increasing the supply of blood and immune cells to the damaged area.

      There are numerous types of white blood cell, but here we are primarily concerned with the lymphocytes, which make up about a quarter of all white blood