There is a widespread belief that some symptoms are ‘physical’ while others are ‘in mind.’ But mind and body are linked in a single complex system – so if one part of the system is damaged or malfunctioning, the rest is bound to be adversely affected.
Illness makes itself known in two ways: by signs – physical changes that can be Jetecte d by other people – and symptoms, which are only known to the person who has them. For example, if you get a cold, your temperature goes up, your nose runs, and you sneeze, these are signs of illness. In addition, however, you may feel feverish, stuffed- up, and tired, and these feelings are symptoms.
Symptoms and signs
Most illnesses produce both symptoms and signs: not only do you feel ill, but other people can see that you are ill, so the question of whether the illness is ‘ real’ or not does arise. However, in some illnesses, the signs are either too subtle to be detected or the condition is not yet understood, so doctors do not recognize them. The only way the illness manifests itself is in unpleasant feelings – symptoms known only to the sufferer. Such conditions are sometimes said to be ‘all in the mind, which until recently meant non-physical. But it is now known that there is no such thing as an entirely non-physical sensation: everything we experience – even our thoughts – has a physical basis in the brain.
Take, for example, the condition of tinnitus, in which sufferers typically complain of persistent ringing or buzzing in the ear. Not so long ago, tinnitus was often assumed to be ‘ in the mind because it had no observable signs that could be detected medically. In recent years, however, imaging equipment has been developed that can show the electrical brain activity of sensations such as hearing. This technology has shown clearly that when tinnitus patients hear a ‘ phantom’ noise, the cells in the brain chat register sound to display the same physical changes that occur when sound waves hit the ear. The sounds heard by tinnitus sufferers are, therefore, no more imaginary than any other sounds – it is just chatting a different mechanism that produces them.
Real feelings from ‘invisible’ causes
In the condition known as phantom limb, people report feeling sensation (including pain) in an arm or leg that has been amputated. This phenomenon was once dismissed as some vague psychological ttachment to the missing body part. Now, however, research has shown that physical sensations can continue to be produced in the brain’s neural ‘ body ma ps’ even in the absence of input from the body. In other words, if the part of the brain that maps the left leg is activated, a person experiences the sensation even if the leg itself is not present. The feeling is identical to when the brain cells are triggered by messages from nerves in an actual leg. This means there is no difference between ‘imaginary’ feelings and ‘ real’ ones – they all stem from the same source: physical changes in the brain.
Sometimes, symptoms can arise that do not have a physical cause. Suppose, for example, someone has an accident during which they suffer a whiplash injury, as can often happen when a car decelerates rapidly. Following the incident, nerves in the neck and spine send signals to the brain cells that register pain in that area. This continuous stimulation sensitizes these cells so that even after the injury has healed, they will be inclined to fire at the least stimulation. The slightest jolt may make them flare up, although an examination would show nothing wrong. In effect, the brain has learned to produce neck pain, even when the signals from. The source has ceased.
Expectations of pain
Another way that feelings may be produced without an obvious cause is through expectation. Suppose, for instance, that your mother suffered from rheumatism, and as a child, you frequently saw her wince when she moved her knee. Furth erm ore, you heard that this type of rheumatism is hereditary. Now, suppose in middle age, when nearly everyone starts to get some joint pain, you feel a slight pain in your knee. Most people would dismiss it as normal wear and tear, but your first thought is likely to be that this is what your mother had. From that moment, you are looking out for the next pain, and any sensation in the knee, however slight, gets immediate attention. Attention is known to amplify feeling – it makes the brain cells associated with the sensation fire more strongly – so what might have been a small twinge can become a searing pain. You may have precisely the same degree of wear in your knee as someone else, but your brain reacts more strongly to it because of your expectations.
Similarly, people can become sensitized to body signals. A person who is constantly looking out at the world rather than inwards is less likely to pay attention to the ongoing buzz of information that the body sends to the brain. Small pains are overlooked, and because they are not noticed, the brain cells that register them do not become sensitized. In contrast, someone who monitors body signals very closely will notice every little sensation, and the brain will react more strongly to any adverse signal.
The simple belief that you have a condition can trigger actual changes in the body that may produce signs of the illness. Just thinking about your blood pressure rising can cause the blood vessels to constrict so that when your blood pressure is measured, it is indeed raised. The precise mechanisms that cause this are not fully understood, but it seems that the thought of a body change feeds back from the cerebral cortex to the limbic areas of the brain that produce that change. This is an example of ‘top-down’ brain processing – conscious thoughts influencing unconscious processes. On rare occasions, the body may erupt in spontaneous lesions. A most dramatic example is the religious phenomenon of ‘stigmata, ‘in which the person develops sores on the hands and feet in empathy with Jesus’ crucifixion wounds (although the causes of this are not fully understood).
Taking control
Just as the brain can produce symptoms of illness, it can also alleviate them. If you can learn to direct your attention away from pain and discomfort and be optimistic about the course of an illness, it will probably cause less distress and wake up more quickly than if you expect it to get worse. Of course, if you have any symptoms that are persistent or could indicate a serious illness, these should always be investigated by a doctor. But if you try to avoid worrying, you may find yourself feeling better without treatment.
CHRONIC FATIGUE SYNDROME
Sometimes known as myalgic encephalomyelitis (ME), chronic fatigue syndrome (CFS) is a classic example of a condition that often has profound symptoms but no signs that the medical profession agrees on. Sufferers feel perpetually tired and may be plagued by all manner of uncomfortable feelings, including muscle and joint pain, weakness, stiffness, dizziness, insomnia, and noticeable mood changes. However, doctors have not yet found any clear signs that identify and distinguish the condition. Some experts have found evidence of viral action, others have detected functional differences in the brains of CFS sufferers, and some maintain the disease is caused by a change in the mitochondria – the ‘batteries’ in body cells that produce energy. Currently, the only diagnostic criterion for CFS is the characteristic bundle of symptoms described by the patient. This leaves the poor CFS sufferer open to the accusation of malingering – because they have no objective, measurable evidence of their illness.
THE PHANTOM NOSE SENSATION
Phantom limb sensation occurs when the brain ‘projects’ a feeling onto a limb that is not there. With the help of a couple of friends and a few minutes to spare, you can get some idea of how this feels.
- Sit in a chair with one friend sitting in another chair in front of you, facing in the same direction, and the second friend standing on your right.
- The standing friend should now take your right index finger in their right hand and use it to stroke and tap the nose of the seated friend in front.
- At the same time, the standing friend must use their own left index finger to tap and stroke your nose, in precise synchrony with the stroking and tapping using your finger of the person in front of you.
- Close your eyes and relax. After about 30 or 40 seconds, you will find that the feeling of tapping and stroking no longer comes from where your nose is but has shifted location to where your finger is stroking your friend‘s nose in front of you. You have created a phantom body part!
