The man who mistook his wife for a hat (11 page)

   The following pieces, extremely short, almost anecdotal, come from the 'Clinical Curio' section of the
British Medical Journal.

   
Phantom Finger

   A sailor accidentally cut off his right index finger. For forty years afterwards he was plagued by an intrusive phantom of the finger

   rigidly extended, as it was when cut off. Whenever he moved his hand toward his face-for example, to eat or to scratch his nose- he was afraid that this phantom finger would poke his eye out. (He knew this to be impossible, but the feeling was irresistible.) He then developed severe sensory diabetic neuropathy and lost all sensation of even having any fingers. The phantom finger disappeared too.

   It is well known that a central pathological disorder, such as a sensory stroke, can 'cure' a phantom. How often does a peripheral pathological disorder have the same effect?

   
Disappearing Phantom Limbs

   All amputees, and all who work with them, know that a phantom limb is essential if an artificial limb is to be used. Dr Michael Kremer writes: 'Its value to the amputee is enormous. I am quite certain that no amputee with an artificial lower limb can walk on it satisfactorily until the body-image, in other words the phantom, is incorporated into it.'

   Thus the disappearance of a phantom may be disastrous, and its recovery, its re-animation, a matter of urgency. This may be effected in all sorts of ways: Weir Mitchell describes how, with faradisation of the brachial plexus, a phantom hand, missing for twenty-five years, was suddenly 'resurrected'. One such patient, under my care, describes how he must 'wake up' his phantom in the mornings: first he flexes the thigh-stump towards him, and then he slaps it sharply-'like a baby's bottom'-several times. On the fifth or sixth slap the phantom suddenly shoots forth, rekindled,
fulgurated,
by the peripheral stimulus. Only then can he put on his prosthesis and walk. What other odd methods (one wonders) are used by amputees?

   
Positional Phantoms

   A patient, Charles D., was referred to us for stumbling, falls and vertigo-there had been unfounded suspicions of labyrinthine disorder. It was evident on closer questioning that what he experi-

   enced was not vertigo at all, but a flutter of ever-changing positional illusions-suddenly the floor seemed further, then suddenly nearer, it pitched, it jerked, it tilted-in his own words 'like a ship in heavy seas'. In consequence he found himself lurching and pitching,
unless he looked down at his feet.
Vision was necessary to show him the true position of his feet and the floor-feel had become grossly unstable and misleading-but sometimes even vision was overwhelmed by feel, so that the floor and his feet
looked
frightening and shifting.

   We soon ascertained that he was suffering from the acute onset of
tabes
-and (in consequence of dorsal root involvement) from a sort of sensory delirium of rapidly fluctuating 'proprioceptive illusions'. Everyone is familiar with the classical end-stage of
tabes,
in which there may be virtual proprioceptive 'blindness' for the legs. Have readers encountered this intermediate stage-of positional phantoms or illusions-due to an acute (and reversible) tabetic delirium?

   The experience this patient recounts reminds me of a singular experience of my own, occurring with the
recovery
from a proprioceptive scotoma. This was described (in A
Leg to Stand On)
as follows:

   I was infinitely unsteady, and had to gaze down. There and then I perceived the source of the commotion. The source was my leg-or, rather, that thing, that featureless cylinder of chalk which served as my leg-that chalky-white abstraction of a leg. Now the cylinder was a thousand feet long, not a matter of two millimetres; now it was fat, now it was thin; now it was tilted this way, now tilted that. It was constantly changing in size and shape, in position and angle, the changes occurring four or five times a second. The extent of transformation and change was immense-there could be a thousandfold switch between successive 'frames' . . .

   
Phantoms
-
Dead or Alive?

   There is often a certain confusion about phantoms-whether they should occur, or not; whether they are pathological, or not; whether

   they are 'real', or not. The literature is confusing, but patients are not-and they clarify matters by describing different
sorts
of phantoms.

   Thus a clear-headed man, with an above-the-knee amputation, described this to me:

   There's this
thing,
this ghost-foot, which sometimes hurts like

   hell-and the toes curl up, or go into spasm. This is worst at

   night, or with the prosthesis off, or when I'm not doing any-

   '' thing. It goes away, when I strap the prosthesis on and walk. I

   ; still feel the leg then, vividly, but it's a
good
phantom, differ-

   , ent-it animates the prosthesis, and allows me to walk.

   With this patient, with all patients, is not
use
all-important, in dispelling a 'bad' (or passive, or pathological) phantom, if it exists; and in keeping the 'good' phantom-that is, the persisting personal limb-memory or limb-image-alive, active, and well, as they need?

   
Postscript

   Many (but not all) patients with phantoms suffer 'phantom pain', or pain in the phantom. Sometimes this has a bizarre quality, but often it is a rather 'ordinary' pain, the persistence of a pain previously present in the limb, or the onset of a pain that might be expected were the limb actually present. I have-since the original publication of this book-received many fascinating letters from patients about this: one such patient speaks of the discomfort of an ingrown toenail, which had not been 'taken care of before amputation, persisting for years after the amputation; but also of an entirely different pain-an excruciating root-pain or 'sciatica' in the phantom-following an acute 'slipped disc', and disappearing with removal of the disc and spinal fusion. Such problems, not at all uncommon, are in no sense 'imaginary', and may indeed be investigated by neurophysiological means.

   Thus, Dr Jonathan Cole, a former student of mine and now a spinal neurophysiologist, describes how in a woman with persistent phantom leg pain, anaesthesia of the spinous ligament with Lig-nocaine caused the phantom to be anaesthetized (indeed to disappear) briefly; but that electrical stimulation of the spinal roots

   produced a sharp tingling pain in the phantom quite different from the dull one which was usually present; whilst stimulation of the spinal cord higher up reduced the phantom pain
(personal communication).
Dr Cole has also presented detailed electrophysiological studies of a patient with a sensory polyneuropathy of fourteen years' duration, very similar in many respects to Christina, the "Disembodied Lady" (see
Proceedings of the Physiological Society,
February 1986, p. 5IP).

   
7

   On the Level

   It is nine years now since I met Mr MacGregor, in the neurology clinic of St. Dunstan's, an old-people's home where I once worked, but I remember him-I see him-as if it were yesterday.

   'What's the problem?' I asked, as he tilted in.

   'Problem? No problem-none that I know of . . . But others keep telling me I lean to the side: "You're like the Leaning Tower of Pisa," they say. "A bit more tilt, and you'll topple right over." '

   'But
you
don't feel any tilt?'

   'I feel fine. I don't know what they mean. How
could
I be tilted without knowing I was?'

   'It sounds a queer business,' I agreed. 'Let's have a look. I'd like to see you stand and take a little stroll-just from here to that wall and back. I want to see for myself,
and 1 want you to see too.
We'll take a videotape of you walking and play it right back.'

   'Suits me, Doc,' he said, and, after a couple of lunges, stood up. What a fine old chap, I thought. Ninety-three-and he doesn't look a day past seventy. Alert, bright as a button. Good for a hundred. And strong as a coal-heaver, even if he does have Parkinson's disease. He was walking, now, confidently, swiftly, but canted over, improbably, a good twenty degrees, his centre of gravity way off to the left, maintaining his balance by the narrowest possible margin.

   'There!' he said with a pleased smile. 'See! No problems-I walked straight as a die.'

   'Did you, indeed, Mr MacGregor?' I asked. 'I want you to judge for yourself.'

   I rewound the tape and played it back. He was profoundly shocked when he saw himself on the screen. His eyes bulged, his jaw dropped, and he muttered, 'I'll be damned!' And then, 'They're right, I
am
over to one side. I
see
it here clear enough, but I've no sense of it. I don't
feel
it.'

   'That's it,' I said. 'That's the heart of the problem.'

   We have five senses in which we glory and which we recognise and celebrate, senses thar constitute the sensible world for us. But there are other senses-secret senses, sixth senses, if you will- equally vital, but unrecognised, and unlauded. These senses, unconscious, automatic, had to be discovered. Historically, indeed, their discovery came lare: what the Victorians vaguely called 'muscle sense'-the awareness of the relative position of trunk and limbs, derived from receptors in the joints and tendons-was only really defined (and named 'proprioception') in the 1890s. And the complex mechanisms and controls by which our bodies are properly aligned and balanced in space-these have only been defined in our own century, and still hold many mysteries. Perhaps it will only be in this space age, with the paradoxical license and hazards of gravity-free life, that we will truly appreciate our inner ears, our vestibules and all the other obscure receptors and reflexes that govern our body orientation. For normal man, in normal situations, they simply do not exist.

   Yet their absence can be quite conspicuous. If there is defective (or distorted) sensation in our overlooked secret senses, what we then experience is profoundly strange, an almost incommunicable equivalent to being blind or being deaf. If proprioception is completely knocked out, the body becomes, so to speak, blind and deaf to itself-and (as the meaning of the Latin root
proprius
hints) ceases to 'own' itself, to feel itself as itself (see Chapter Three, 'The Disembodied Lady').

   The old man suddenly became intent, his brows knitted, his lips pursed. He stood motionless, in deep thought, presenting the picture that I love to see: a patient in the actual moment of discovery-half-appalled, half-amused-seeing for the first time exactly what is wrong and, in the same moment, exactly what there is to be done. This
is
the therapeutic moment.

   'Let me think, let me think,' he murmured, half to himself, drawing his shaggy white brows down over his eyes and emphasising each point with his powerful, gnarled hands. 'Let me think. You think with me-there must be an answer! I tilt to one side, and I can't tell it, right? There
should
be some feeling, a clear signal, but it's not there, right?' He paused. 'I used to be a carpenter,' he said, his face lighting up. 'We would always use a spirit level to tell whether a surface was level or not, or whether it was tilted from the vertical or not. Is there a sort of spirit level in the brain?'

   I nodded.

   'Can it be knocked out by Parkinson's disease?'

   I nodded again.

   'Is
this
what has happened with me?'

   I nodded a third time and said, 'Yes. Yes. Yes.'

   In speaking of such a spirit level, Mr MacGregor had hit on a fundamental analogy, a metaphor for an essential control system in the brain. Parts of the inner ear are indeed physically-literally-like levels; the labyrinth consists of semicircular canals containing liquid whose motion is continually monitored. But it was not these, as such, that were essentially at fault; rather, it was his ability to use his balance organs, in conjunction with the body's sense of itself and with its visual picture of the world. Mr MacGregor's homely symbol applies not just to the labyrinth but also to the complex
integration
of the three secret senses: the labyrinthine, the proprioceptive, and the visual. It is this synthesis that is impaired in Parkinsonism.

   The most profound (and most practical) studies of such integrations-and of their singular disintegrations in Parkinsonism- were made by the late, great Purdon Martin and are to be found in his remarkable book
The Basal Ganglia and Posture
(originally published in 1967, but continually revised and expanded in the ensuing years; he was just completing a new edition when he died recently). Speaking of this integration, this integrator, in the brain, Purdon Martin writes 'There must be some centre or "higher authority" in the brain . . . some "controller" we may say. This

   controller or higher authority must be informed of the state of stability or instability of the body.'

   In the section on 'tilting reactions' Purdon Martin emphasises the threefold contribution to the maintenance of a stable and upright posture, and he notes how commonly its subtle balance is upset in Parkinsonism-how, in particular, 'it is usual for the labyrinthine element to be lost before the proprioceptive and the visual'. This triple control system, he implies, is such that
one
sense,
one
control, can compensate for the others-not wholly (since the senses differ in their capabilities) but in part, at least, and to a useful degree. Visual reflexes and controls are perhaps the least important-normally. So long as our vestibular and proprioceptive systems are intact, we are perfectly stable with our eyes closed. We do not tilt or lean or fall over the moment we close our eyes. But the precariously balanced Parkinsonian may do so. (One often sees Parkinsonian patients sitting in the most grossly tilted positions, with no awareness that this is the case. But let a mirror be provided, so they can
see
their positions, and they instantly straighten up.)