IELTS Academic Reading Practice Test 330

Hippocrates is the most famous physician of the ancient world, yet almost nothing about him can be stated with certainty except that he lived. He was born on the island of Cos, probably around 460 BC, and died at Larissa, in Thessaly, at an advanced age, some time in the 370s. Plato mentions him twice, and Aristotle refers to him as a physician. The flattering title by which he is now known everywhere, 'the father of medicine', was not used in his lifetime and appears only in much later writers.

What has come down to us under his name is not a single body of work but a collection of about sixty treatises, known as the Hippocratic Corpus and written in the Ionic dialect of Greek. They cover anatomy, surgery, diet, epidemics, medical ethics and the doctor's conduct. Internal evidence shows that they were composed over more than a century by several authors, who sometimes contradict one another. Because no contemporary account of his own teaching survives, scholars cannot establish which, if any, of the treatises Hippocrates wrote himself. The collection was later assembled and catalogued at the library of Alexandria, and none of the treatises is signed.

The theoretical centrepiece of the collection is the doctrine of the four humours, set out most clearly in the treatise On the Nature of Man. The body was thought to contain four fluids — blood, phlegm, yellow bile and black bile — and health was understood as the right balance between them. Illness arose when one fluid became excessive or moved to the wrong part of the body, and treatment therefore aimed at removing or reducing it. Diet and exercise were adjusted, and patients were bled or given emetics and purgatives. The four humours were linked to the seasons and, much later, to four temperaments: the sanguine, the phlegmatic, the choleric and the melancholic.

Just as influential was the insistence, in the treatise On the Sacred Disease, that illness had natural rather than supernatural causes. The subject was epilepsy, which contemporaries blamed on the gods. The author would have none of it: the condition, the writer maintained, was no more sacred than any other and its origin lay in the brain. That combination of natural explanation with close observation became the mark of Hippocratic writing. The case notes in the treatises known as the Epidemics follow individual patients from day to day, and the description of the faces of the dying, still called the Hippocratic face, comes from another treatise altogether.

The best-known text in the collection is the oath, which was probably sworn by a small group of pupils rather than by every physician in Greece. Its opening invokes Apollo, Asclepius, Hygieia and Panacea, and the novice promises to regard his teacher as a parent.

The oath then sets out a series of prohibitions: the doctor will not give a deadly drug to anyone who asks for one, will not suggest such a plan, and will not give a woman a pessary to cause an abortion. Surgery is left to others. One of its most admired clauses is the promise to keep silent about whatever is seen or heard in the course of treatment, a remarkably early statement of confidentiality.

Hippocratic ideas survived largely because Galen, a Greek physician working in Rome in the second century AD, adopted them. Galen began his career treating gladiators at Pergamon and later became physician to the emperor Marcus Aurelius. He wrote enormously, and his synthesis of humoral theory with anatomy and physiology became the standard for the next fourteen centuries. Translated into Syriac, Arabic and Latin, his works were studied in the Islamic world and in the medical schools of medieval Europe, where Hippocrates was read chiefly through Galen's eyes. Galen's own books circulated more widely than the Hippocratic texts themselves.

The humoral system began to crumble in the nineteenth century. In Paris in the 1830s the physician Pierre Louis analysed the records of patients with pneumonia and concluded that bleeding them made no difference to whether they recovered; counting cases rather than trusting impressions was itself an innovation. Pathological anatomy, and later the germ theory of disease, offered a different account of what made people ill. Leeches and lancets slowly disappeared from the wards, and the four humours became a subject for historians.

The oath itself has not been abandoned. In 1948 the World Medical Association adopted the Declaration of Geneva as a modern restatement of medical ethics, in the shadow of crimes committed by doctors under the Nazi regime. It has been revised several times since. Modern versions leave out the ancient prohibition of surgery and the ban on abortion, and add commitments to respect patients whatever their circumstances. Graduates of many medical schools still swear an oath of some kind, though its wording differs from one country to another.

What remains most valuable, perhaps, is not any particular doctrine but an attitude. The Hippocratic writers insisted that the doctor's first duty was to the welfare of the patient, and that treatment should follow observation rather than speculation. They were often wrong about the body — one of them described the brain as a gland — but they were wrong in ways that could be corrected by further observation. That is a considerable legacy for a man about whom so little is known.

Every sound a person makes with the voice begins with an act of obstruction. Air leaves the lungs and passes through a narrow tube in the neck, and across that tube stretch two small folds of tissue. When they are drawn together and air is forced through them, they vibrate, and the buzz they produce becomes speech, song, a cry or a whisper. The structure that houses them, the larynx, sits at the top of the trachea and is a valve as well as an instrument: it must open for breathing, close for swallowing and vibrate for speech.

The larynx is built from a framework of cartilage. The largest piece is the thyroid cartilage, a shield-shaped plate that forms the ridge visible at the front of the neck and is considerably more prominent in men, in whom it enlarges at puberty. Below it lies the cricoid cartilage, the only complete ring in the airway, and above it hangs the horseshoe-shaped hyoid bone, unusual in being connected to no other bone. Inside the framework sit two small pyramid-shaped cartilages called the arytenoids, which swivel and slide on the cricoid and act as the hinges of the voice.

Stretched between the thyroid cartilage at the front and the arytenoids at the back are the vocal folds, often called the vocal cords, though they are not cords but shelves of tissue containing ligament and muscle and covered with a thin layer of mucous membrane. The gap between them is the glottis. For quiet breathing the arytenoids swing the folds wide apart, so that the glottis forms a triangle; for speech they bring the folds together, leaving only a narrow slit. The folds of an adult man are a little longer than those of an adult woman, which is one reason male voices are generally lower.

How the folds produce sound is described by the myoelastic-aerodynamic theory, set out in the 1950s by the Dutch researcher Janwillem van den Berg. As air is held back below the closed folds, pressure builds until it forces them apart; the flow through the narrowed gap then lowers the pressure between them, and their own elasticity snaps them shut again. The rate of this cycle determines the pitch of the voice. In ordinary speech the folds of an adult man open and close roughly 100 to 150 times a second, and those of an adult woman about twice as often. Trained singers can vary the rate over two octaves or more.

The buzz from the folds is not yet a voice. Above the glottis, the throat, mouth and nasal cavity together form the vocal tract, a tube about seventeen centimetres long in an adult, which acts as a resonator. Its shape selects and amplifies certain frequencies, called formants, and suppresses others. The tongue, lips, jaw and soft palate change that shape, and therefore the formants, and so turn the same buzz into different vowels. Some speech sounds, such as s and f, are made with the folds held apart, so that air hisses through the gap without setting them in motion.

The cricothyroid muscle, which tilts the thyroid cartilage forward, stretches and thins the folds and raises the pitch; the muscle inside the folds does the opposite, while loudness depends chiefly on how hard the lungs push. The signals to these muscles travel along the recurrent laryngeal nerve, a branch of the vagus nerve that takes an extraordinary detour. Instead of running straight to the larynx it loops down into the chest, around the aorta on the left and an artery beneath the collarbone on the right, before climbing back up the neck. Damage to it during thyroid surgery is a well-known cause of a hoarse voice.

The larynx is also a sphincter, and it closes firmly when a person swallows or lifts something heavy. Swallowing is a precisely timed sequence: the larynx rises, the epiglottis, a leaf-shaped flap above the opening, tips backwards, and the folds shut, so that food is directed into the oesophagus behind. Human anatomy makes this necessary, because the airway and the food passage share the same entrance. The human larynx also sits lower in the neck than that of other primates, and many researchers have argued that this descent gives people the space to produce a wide range of vowel sounds, though the explanation is not universally accepted.

Quite how the folds behave in detail is still debated. They do not simply flap open and shut; high-speed films show a travelling wave moving along the surface of each fold, and the stiffness of the tissue varies from one layer to the next. Why voices change with age is also only partly understood: the folds thin, the muscles weaken and the cartilage stiffens, but the amount varies greatly between individuals. The false folds, a second pair of ridges above the true ones, are thought to help with closure, but they are difficult to study.

Research on the voice is increasingly technological. High-speed cameras record the folds at several thousand frames a second, and computer models simulate how air and tissue interact. Tissue engineers have tried to grow replacement tissue for folds damaged by scarring, and clinicians inject gels and other materials to restore their shape, so far with mixed results. Voice therapy, which trains patients to use the voice more efficiently, remains the first treatment offered for many voice problems, and it is often supported by biofeedback displays of pitch and loudness.

The larynx, in the end, is an organ with three incompatible jobs: it must let air in, keep food out and vibrate for hours a day. That it manages all three, in most people, for a lifetime, is one of the quieter achievements of the human body.

Anyone with a smartphone can now download software that counts steps, tracks moods, records a heartbeat or teaches breathing exercises. Estimates of the number of health-related apps on offer vary wildly, but all run into the hundreds of thousands. Most are harmless. A few could seriously injure someone if they were wrong. Some are endorsed by hospitals; others are the work of a single enthusiast. The question facing regulators is how to tell the difference without drowning a young industry in paperwork — or, put another way, whether software that claims to look after our health should be regulated in the same way as a medicine.

The range is the difficulty. At one end is an app into which a patient types the blood pressure readings taken at home, or which reminds them to take a tablet; it stores and displays information but reaches no conclusions of its own. At the other is software that calculates how much insulin a person with diabetes should inject before a meal. A wrong calculation can put the user in a coma. Other apps read a recording of the heart's electrical activity and announce that the rhythm is abnormal. Between the two extremes lies everything else.

Regulators have begun to draw lines. In the European Union, software intended to diagnose, monitor or treat a disease counts as a medical device and must carry a CE mark. In the United States the Food and Drug Administration has taken a similar approach, while declining to regulate apps that merely encourage a healthy lifestyle. An insulin calculator, by these rules, is a device; a step counter is not. An app that simply carries messages between a patient and a doctor falls outside the rules too, although doctors have raised concerns about the quality of advice given through such services. Much therefore depends on how a company describes its product.

Some consumer products have crossed the line already. In 2018 the American regulator cleared a feature on a smartwatch that records a single-lead electrocardiogram and alerts the wearer to an irregular rhythm, making it, in effect, a medical device worn on the wrist. Approval followed evidence that the software could detect atrial fibrillation, a common and often symptomless disturbance of heart rhythm. Here, at least, the machinery of medical regulation and the consumer electronics industry have met and reached an understanding.

Evidence is the weak point elsewhere. App-based courses of cognitive behavioural therapy have been recommended by national health bodies for insomnia, and the evidence for them in insomnia, anxiety and mild depression is reasonably good. But reviews of the thousands of apps that claim to treat mental health problems have repeatedly found that most have never been tested. Some make claims no study would support, and many are removed from the app stores within a few years of launch. An app that has never been evaluated cannot be said to work, and regulators have limited capacity to examine them.

Privacy is the other concern, and it is not a matter of physical injury. Health information is among the most sensitive data a person generates, and under European law it belongs to a special category that requires explicit consent. Yet analyses of popular apps have found tracking software built into them, and privacy policies that are vague or absent. A step counter that quietly reveals to an insurer that its user is at home all day is doing harm, even though nothing about it is medical. Consent screens are long, and few users read them.

The industry's objection is that rules designed for pills and scalpels fit software badly. A medicine is fixed when it is approved; an app is updated every few weeks, and a licence granted in January may describe something that no longer exists in June. Getting a CE mark can cost a small developer tens of thousands of pounds and take a year, which favours established companies and may keep useful products from patients. Requiring a step counter to prove its safety would be disproportionate.

These are real difficulties, but they argue for a different kind of regulation, not for none. The sensible approach is one graded by risk. Software that merely records what a patient enters should face no approval process at all, but should be obliged to say plainly what it does with the data and to whom it passes them.

Apps that make therapeutic claims should have to publish the evidence behind those claims, in a form that a clinician can check. Only the small number that could cause serious harm if they failed should need individual clearance before they are sold. None of this requires a new international agency; it requires existing regulators to publish clearer standards.

That is not regulation like a medicine; it is regulation like what it is. Medicines are approved once, in a fixed form; software is a service, and it needs continuous, lighter supervision, with developers required to report changes that affect safety. The right question for a regulator is not whether an app calls itself medical, but what happens to the user if it is wrong. By that test a great many apps deserve no attention at all, and a small but growing number deserve a great deal. Whether they will get it is another matter.