Exproloring Exproloring Micro-Micro-

Movements for Diagnostics Movements for Diagnostics

of Neurological Problemsof Neurological Problems

Jalo Kääminen

Department of Computer Sciences

University of Tampere Finland

Jalo.Kaaminen@uta.fi

April, 2005

AAFG 2005

J.Kääminen p 02_19 04.04.2005

The original goal of Finger Dexterity software (FDTT) was the training

of fine accurate motor movement.

The game can be used as a test to measure finger dexterity and hand-

eye coordination.

The software allows recording and estimation of an individual's ability to

move the fingers and to control fine micro-movements using a stylus.

FDexterity

We explored the possibility to use FDTT to record micro-movements

and behavioral artifacts for earlier diagnostics of neurological problems

in children and adults.

Tremor can be as a symptom of such neurological diseases as

Parkinson's disease, multiple sclerosis, diseases of or damage to the

cerebellum, or as a result of some drugs' application.

Coordination problems in Parkinson’s disease include difficulty in

carrying out such tasks as brushing teeth, walking, speaking, and

writing, and worsening rigidity.

While the more obvious Parkinson’s symptoms, such as visible

tremors and muscular rigidity, appear at a later stage in the progress of

the disease, the level of deterioration in a patient’s ability to control

micromovements must be detected as early as possible.

J.Kääminen p 03_19 04.04.2005

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A successful test may help in the early diagnostics of diseases such as Parkinson’s or the drugs dependence or other neurological syndromes.

This could open the way for treatment that

may delay the progression of this presently

incurable disease.

Several techniques have been proposed, most of them with complex test procedured and specialized harware.

J.Kääminen p 04_19 04.04.2005

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Research Questions are:

Could relevant information be gained from FDTT recordings to

estimate whether the technique could be used as a screening

method?

Does tremor have an impact on a personal game performance?

How do coordination problems show themselves in the recordings?

J.Kääminen p 05_19 04.04.2005

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J.Kääminen p 06_19 04.04.2005

There are two fields when player start the game.

The big field restricted with white border, where the graphs appears.

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Play!

Finger Dexterity Test & Training (Game)

The green rectangle is the green start zone.

To complete the game the player need to cross the red rectangle.

The small field is intended for input.

The scanpath is being recorded.

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Ave. X Ave. Y

J.Kääminen p 07_19 04.04.2005

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1/130pxls 2/246pxls 3/228pxls 4/232pxls 5/236pxls

5 different contour graphs have been used in testing.

The graphs' sampling is homogeneous enough both on X and Y axis.

Pilot Game Testing

8 subjects: with normal vision and hearing, ages 10-59

Software: ‘Finger Dexterity’ game, iPAQ pocket PC version

Hardware: iPAQ pocket PC with touchscreen and stylus input

Conditions: a normal room, with silent background music to release

any tension and concern for how results might be evaluated.

Training: A brief training session preceded the actual recording to

make sure the subject knows how to handle the pen and use the

application. Usually, 2-4 inputs were enough to learn the

application well to carry out the actual recordings. Generally, the

software was surprisingly easy to adopt even with persons over 50

years old with normal vision.

J.Kääminen p 08_19 4.04.2005

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Recordings: Each subject has implemented 20 recorded trials.

Log file format:

Graph number

Scale/zoom factor

Time, s, to complete the task

Errors (out-of-screen)

The average deviation on X, pxls

The average deviation in Y, pxls

Correlation on X

Correlation on Y

Correlation on XY

J.Kääminen p 09_19 04.04.2005

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The average data in total performance of the subjects were very

close to the mean value.

When there is a problem in micro-motorics or unknown ethiology,

the problem has to be detected:

(next, the cases are explained in detail)

J.Kääminen p 10_19 04.04.2005

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Data analysis & Results

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Graph number

Corr. on XY

Subject 1 Subject 3

Subject 4 Subject 5

Subject 6 Subject 8Subject 2 Subject 1 with tremor simulationSubject 7 Average

J.Kääminen p 11_19 04.04.2005

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A surprise for the person himself

Mean values for corr. on XY

J.Kääminen p 12_19 04.04.2005

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The effects of tremor and hand-eye coordination

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Corr. on XY Subject 1 Subject 1 with simulation Subject 7 Average

J.Kääminen p 13_19 04.04.2005

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The second graph ε is quite sensitive than others.

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Subject1:

Subject 2: Subject 3:

Subject1 with simulation:

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J.Kääminen p 14_19 04.04.2005

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Subject1: Subject7:

Graph ε , Corr. on Y-axis, the subjects 1 & 7

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Conclusions:

When there is a problem, there is a problem: Coordination problems

show themselves clearly in the data even though they no problems

had been previously detected by the person himself.

The variation in the total results is very small.

It would be relatively easy to figure out normal performance in the test

proposed.

Age itself doesn’t have an impact on the results. The best results were

collected with the second oldest subject. But the population sample

under current investigation was restricted enough to make any final

decision.The test might be applicable to people of various ages.

Normal vision (or corrected with eyeglasses) is the only requirement.

J.Kääminen p 15_19 04.04.2005

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J.Kääminen p 16_19 04.04.2005

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Tremor affects the results slightly but detectably.

Simulated tremor had a visible effect on the subject 1 results (The

subject 4 had exceptional problems in test setting with stylus during

the inputs 10-20. If only successful recordings are considered in the

study, his results are just the average and noticeably better than the

subject 1 with tremor simulation.)

Still, there are some additional software options (zoom) which were

not tested yet. That could increase a sensitivity of the method

especially in detecting the effects of tremor.

J.Kääminen p 17_XX 04.04.2005

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Constraints:

The study was carried out in the field of human-computer-interaction.

Further research should be done under medical supervision.

Recordings among people suffering from various neurological

diseases might be carried out to estimate the values of deviation

from the normal.

J.Kääminen p 18_19 04.04.2005

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References:

Bain PG, Findley LJ, Atchison P, Behari M, Vidailhet M, Gresty M, Rothwell

JC, Thompson PD, Marsden CD. Assessing tremor severity Journal of

Neurology, Neurosurgery & Psychiatry.1993;56:868-73.

van Emmerik, R.E.A., Wagenaar, R.C.(1995) Tremor and symmetry

properties in bimanual coordination in Parkinson’s disease. In: Bardy, B.G.,

Bootsma, R.J. & Guiard, Y. (eds.) Studies in Perception and Action.

Lawrence Erlbaum, pp. 61-64.

Sharon Smaga, Tremor. American Family Physician, 68, 8, (Oct. 2003),

1542-1552.

Essential Tremor: A Practical Guide to Evaluation, Diagnosis, and

Treatment, Vol. 19 No. 2 ISSN 0264-6404 May 2001.

http://www.baylorcme.org/tremor/tremor.pdf

J.Kääminen p 19_19 04.04.2005

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