The Treatment of Akinesia using Virtual Images

by Jerrold D. Prothero

Kinesia Paradoxa

The classic study on kinesia paradoxa, the ability of akinetic persons to move significantly more naturally in the presence of visual cues at their feet, is provided by Martin in 1967 [45]. Martin examined various configurations of objects such as blocks and tape to determine their effectiveness as visual cues. He concluded that:

Transverse lines of almost any kind across his path are of some help to the average Parkinsonian patient, and almost the best effects are obtained from bold lines, an inch or more wide, and of a colour contrasting with that of the floor or ground. Thus white lines, one or two inches wide, and eighteen inches or so apart on a dark ground produce a pronounced, and sometimes dramatic, effect, enabling a patient who seemed unable to walk, or the shuffler on short steps, to step out strongly. It may be that strips of light-coloured cardboard or linoleum or merely paper are more effective, and certainly obstacles of the nature of pieces of wood, two or three inches high, or bricks, seem to produce the maximum effect. The influence of these stimuli may be a little greater indoors, where there are other visual points and lines of reference, than out on an open space.

...The patient may seem to be making an effort to step over the lines or obstacles, but without seeing them his voluntary effort is of no avail. Occasionally, if the patient is blindfolded, the memory of the obstacle will enable him to start, but more often this procedure fails.

Usually the transverse line or obstacle is ineffective until the patient comes within stepping distance of it, i.e. so close that he can step over it.

...Zig-zag lines are less effective than transverse, and strips without contrast of colour are somewhat less effective than contrasting ones, though the difference is not great when the patient attends to them.

...A moving line, drawn along the ground in front of him, seemed to have no effect on one of our patients, and lines not on the ground (for example, on a suitably striped skirt), were also without effect. On the other hand there can be little doubt that the influence of a series of transverse lines or obstacles is at least one of the factors that enable so many Parkinsonian patients to mount stairs much better than they walk on the level.

A number of studies have also mentioned the effectiveness of an upturned walking stick in providing a cue for treating freezing episodes [15,14,20].

Other patients have used the trick of dropping paper balls to get started; for instances, Sacks [63] (p. 296) mentions that ``Miss D.''

``had various ways of `defreezing' herself if she chanced to freeze in her walking: she would carry in one hand a supply of minute paper balls of which she would now let one drop to the ground: its tiny whiteness immediately `incited' or `commanded' her to take a step, and thus allowed her to break loose from the freeze and resume her normal walking pattern... Such methods are discovered or devised by all gifted post-encephalitic and Parkinsonian patients, and I have learned more from such patients than from a library of volumes.''

It should be mentioned that for ordinary Parkinson's disease, kinesia paradoxa possibly only occurs in the presence of levodopa therapy. Hardie [26] observes

``The phenomenon of kinesia paradoxa evidently became increasingly rare as the number of postencephalitic Parkinsonian survivors dwindled and it does not seem to be a feature of untreated Parkinson's disease. It was not until the advent of levodopa therapy and recognition of the remarkable `on-off' fluctuations with which it was associated that anything comparable was to be seen again.''

Some of the research related to the underlying causes of kinesia paradoxa is discussed in Appendix C.

While the scope of this thesis has dictated a presentation of kinesia paradoxa strictly in terms of visual cuing, this is somewhat misleading. It seems that akinesia is related to losing the ability to sequence motor instructions internally; visual cues are one way of providing an external means of sequencing motor instructions. However, other means are also available: one is music. According to Sacks [63] (pp. 294--5),

This power of music to integrate and cure, to liberate the Parkinsonian and give him freedom while it lasts (`You are the music/ while the music lasts', T.S. Eliot), is quite fundamental, and seen in every patient. This was shown beautifully, and discussed with great insight, by Edith T., a former music teacher. She said that she had become `graceless' with the onset of Parkinsonism, that her movements had become `wooden, mechanical --- like a robot or doll', that she had lost her former `naturalness' and `musicalness'. Fortunately, she added, the disease was `accompanied by its own cure'. We raised an eyebrow: `Music,' she said, `as I am unmusicked, I must be remusicked.' Often, she said, she would find herself `frozen', utterly motionless, deprived of the power, the impulse, the thought, of any motion; she felt at such times `like a still photo, a frozen frame'--- a mere optical flat, without substance or life. In this state, this statelessness, this timeless irreality, she would remain, motionless-helpless, until music came: `Songs, tunes I knew from years ago, catchy tunes, rhythmic tunes, the sort I loved to dance to.'

With this sudden imagining of music, this coming of spontaneous inner music, the power of motion, action, would suddenly return, and the sense of substance and restored personality and reality; now, as she put it, she could `dance out of the frame', the flat frozen visualness in which she was trapped, and move freely and gracefully: `It was like suddenly remembering myself, my own living tune.' But then, just as suddenly, the inner music would cease, and with this all motion and actuality would vanish, and she would fall instantly, once again, into a Parkinsonian abyss.