CONCENTRATION TESTS

An Application of Gaze Tracker to Concentration Exercises

Bartosz Kunka, Andrzej Czyzewski and Bozena Kostek

Multimedia Systems Department, Gdansk University of Technology, Narutowicza str. 11/12, Gdansk, Poland

Keywords: Concentration test, Gaze tracking, Multimodal interface.

Abstract: This paper presents different methods of concentration tests. Some existing methods are reviewed and more

thoroughly described. The gaze tracking system developed at the Multimedia Systems Department of the

Gdańsk University of Technology is presented and its principle of working is explained. Performed tests of

the gaze tracker system show that it could make a useful system for concentration exercises. Some selected

applications of the gaze tracker to concentration tests are also discussed in the paper.

1 INTRODUCTION

Nowadays, people are attacked by information

constantly. Children are even more susceptible to

media exposure because they are not critical in their

perception. Consequently, many of them cannot

concentrate on one activity. Therefore, a method of

exercising concentration was proposed by the

Multimedia Systems Department (MSD) of Gdansk

University of Technology. This approach consists in

using an inexpensive gaze tracking system

developed in the MSD. The gaze tracker is a tool

which allows for tracking eye movements and for

estimating a localization of the fixation point that is

a point a user is looking at the computer screen. This

paper describes shortly some existing methods of

concentration tests, then presents the gaze tracking

system developed at the MSD and points out its

potential as a practical and easily accessible tool for

concentration exercises.

2 EXISTING METHODS OF

CONCENTRATION TESTS

For many years people have tried to develop

methods of concentration enhancement.

Concentration tests could be reviewed in many

aspects. One of the approaches is an analysis of the

attention level which helps checking if a user is not

tired or sleepy. Other tests are used to select a person

who needs to process information in a systematic

way accurately. Another group of concentration tests

enables to develop skills and possibilities of autistic

children and those affected by the ADHD (ADHD -

Attention Deficit/Hyperactivity Disorder).

2.1 Standard Tests

In the Internet we can find many interesting

exercises, applications and movies which could be

helpful in concentration tests.

Some methods consist in ability to perform tasks

at the same time or while solving a logical task. One

of the examples of such a method could be an

application described below. There is a matrix with

values from 0 to 3 as shown in Fig. 1a. A user

should set all values (buttons) to ‘0’ but when he/she

chooses one button, then its value and values of four

neighboring buttons are decreased by ‘1’. This is

shown in Fig. 1b. When a user sets all values faster,

he/she scores more (BM, website).

Figure 1: a) Matrix with input values; b) Chosen part of

matrix with updated values (BM, website).

Other methods available in the Internet are some

interactive games. An example of this approach is

119

Kunka B., Czyzewski A. and Kostek B. (2009).

CONCENTRATION TESTS - An Application of Gaze Tracker to Concentration Exercises.

In Proceedings of the First International Conference on Computer Supported Education, pages 119-122

DOI: 10.5220/0001975901190122

 SciTePress

the Supermarket Game. It is basically a labyrinth

that must be traversed while the player acquires

items shown in the shopping list. An additional

restriction is that the player can cross most of the

paths only once. The game includes specific rules

and challenges that allow for scoring positively, by

acquiring a correct item, or negatively, in case the

player commits a fault by breaking one of the rules.

An important criterion is the elapsing time

(Andrande et al., 2006).

2.2 Specialized Tests

There are concentration tests that focus on autistic

children and those affected by the ADHD. Methods

used in that area are more complex and typically

may require more hardware equipment.

Most systems dedicated to children with

neurological disorders are based on processing EEG

signals (Electroencephalography). EEG signals

contain information on electrical potentials in

various parts of the brain, thus they are the recorded

electrical activity of the brain.

3 GAZE TRACKING

TECHNIQUE

As mentioned in Introduction, the gaze tracking

system engineered at the MSD enables to track

fixation point on the computer screen. The current

version of the system works correctly with definite

space resolution. It is assumed that the gaze tracker

system may be applied to concentration exercises

(Czyzewski et al., 2008).

3.1 System Description

The gaze tracking system developed at the MSD is

based on infrared (IR) illumination. Lighting IR

LEDs cause arising characteristic corneal

reflections, technically known as “glints”. Glints are

usually the brightest points in the image. They form

a shape of quadrangle because they are created by

four sections of LEDs located in four display

corners. Also, localization of glints is characteristic.

They are localized in the iris and the pupil. The pupil

is always very bright because of IR LED illuminator

beaming light along the camera optical axis.

Therefore, contrast between the brightness of the iris

and pupil is relatively large, therefore finding area

with glints is possible. All data gathered are used in

the eye detection procedure and they are usually

sufficient to detect eye regions correctly. Processed

images are recorded in grey scale because they were

IR-illuminated. The hardware configuration of the

developed gaze tracker system along with the

detected region of eye are presented in Fig. 2.

Figure 2: a) System configuration of the gaze tracker

developed by the MSD; b) Part of the image with the

detected eye region.

The main assumption of the gaze tracking system

is hands-free application. The second assumption

concerns the head position. A user should sit in front

of the screen at a distance of about 60cm. The

system does not require to be seated very still but the

user should try not to move his head too much. The

latter assumption is connected to the system

accuracy. The space resolution of the system, also

associated with the accuracy, amounts to 9 parts of

the screen. In fact, the gaze tracker works correctly

and discerns each of 9 areas with a sufficient

accuracy.

3.2 Results and System Accuracy

The current version of the gaze tracking system is

unaffected by different eye colors and small head

movements. Influence of light conditions on correct

working is described below. Tests were organized in

real conditions involving 50 persons. Results of

these tests are presented in Fig. 3.

The lens used had a focal length of 16mm and

the chosen image resolution was 800x600 pixels.

The outcome of the tests indicates that gaze

tracking system engineered in MSD allows to apply

this technology in concentration tests. Group of 50

persons was tested in equal conditions. Results of

person who reached the worst effectiveness were

characterized by more scattering than results of

person who reached the best effectiveness.

Moreover, some regions were detected incorrectly

what is not seen in this picture (Fig. 3). The cause of

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the effectiveness differences could be light

conditions or too large head movements.

Figure 3: Gathered outcome of the worst, normal and the

best results of tested persons.

It is proved that additional infrared emission,

contained in sun radiation, disturbs the gaze tracker

based on infrared illumination. Therefore, the gaze

tracker depends on light conditions, unfortunately.

Nevertheless, the gaze tracker could be regarded

as a promising solution for concentration tests,

particularly in systems with space resolution of 9

areas per screen.

4 GAZE TRACKER IN

CONCENTRATION TESTS

4.1 Concentration

The gaze tracking system could be applied in two

types of concentration tests. Firstly, a user is

engaged in an exercise, i.e. it is an interactive

activity. For example, he/she tracks the moving

object (as shown in Fig. 4). The second type is the

tracking of the user’s passive activity. He/she can

read a text or watch objects on the screen and the

gaze tracking system analyzes the fixation points in

real time.

It is worth to mention that concentration is

related to the commitment of a user, enthusiasm for

the task, skills to perform the task, psychological

and physical state and environment (UC, website).

Therefore, the problem of concentration tests is

more complex, and fully measurable.

4.2 MSD Concentration Test

There are many research studies associated with

applying eye tracking methods to improvement of

the learning process. An example of this is AdeLe, a

framework for adaptive e-learning using eye

tracking technology. The AdeLe utilizes the

commercial eye tracking system (Tobii 1750). It

enables to obtain a very high accuracy and it is

unaffected by eye changes (e.g. blinking), head

movements and light conditions. Therefore, AdeLe

has more possibilities of the concentration

monitoring. It is possible to measure a saccadic

velocity, blink velocity and the degree of the eyelid

openness. Saccadic velocity is said to decrease with

increasing tiredness and to increase with increasing

task difficulty (Pivec et al., 2006).

Effectiveness of the gaze tracking system,

developed in MSD, is lower than AdeLe but its

functionality could be useful in improving methods

of concentration exercises as well. The MSD

proposes some applications cooperating with the

gaze tracking system. They are directly associated

with time measurement. Two of them have been

currently engineered and tested. It is worth to

mention that the gaze tracking system is calibrated

for each user therefore not looking at the screen is

detected as well.

The first application is based on the redeveloped

version of one of the methods based on animation,

described in Section 2. The main idea of this

exercise is looking at the indicated object in the

image and gaze-tracking it. The application enables

to choose one of two options: smooth/sudden and

random changes of the object movements. The user

is distracted by other objects which move in the

image freely. A change of game levels is possible. In

the easiest configuration distracting elements move

relatively slow. The most difficult level contains

quickly moving and flickering objects. An additional

difficulty is the moving background. During each

exercise time of the object being correctly tracked is

measured. A so-called ‘concentration ratio’ (CR)

computed according to formula (1) can be

determined:

100%

=⋅

(1)

–

concentration ratio;

–

time of correct fixation (when the user

tracks an object correctly);

–

total time of exercise.

An example of the screenshot of the application

interface is shown in Fig. 4.

CONCENTRATION TESTS - An Application of Gaze Tracker to Concentration Exercises

121

Figure 4: An example of the screenshot of the user

interface; the bee is the tracked object.

The second proposition of application is slightly

similar to creating a visual heatmap. A visual

heatmap is a graphical representation of the

distribution of screenparts observed by the user. The

frequency of looking at the objects in the image

generates colors – from blue (the most infrequent) to

red (the most frequent). This application does not

force a user to constant concentration but check

what elements of the given image are more

interesting than the others. This approach enables to

find out how long the user can concentrate on one

object and how often he/she changes a direction of

looking. The map of transitions is generated in order

to visualize these changes. A therapist can observe a

heatmap generated in real time or screenshots with

heatmaps after finishing a test. The project of the

graphical interface of this application with an

example of the visual heatmap is shown in Fig. 5.

Figure 5: An example of the visual heatmap.

5 CONCLUSIONS

Nowadays, concentration tests become more

frequent, and they are often used in education.

Paying attention is a skill that is very important

during the learning process and the career

development as well.

The rapid development of multimedia

technologies enable to apply interactive methods in

concentration exercises. The existing AdeLe

framework is directly connected to using expensive

eye tracking system. Therefore, its common usage is

still impossible. Initial tests of gaze tracking system

proposed at the Multimedia Systems Department

allow for regarding this system as a promising

approach of modern solution to the concentration

exercises. Children who were tested with this

interface very easily and correctly understood and

follow all guidelines. Besides, working with the gaze

tracker was pleasant for them. Thus, a game-like

exercise with such an interface could be very

pleasant for a child and at the same time may be an

attention examination tool for parents or therapists.

Even though applying the gaze tracking system

in concentration tests is not a fully objective

measure because it doesn’t e.g. examine

commitment of the user, enthusiasm for the task,

skills to perform the task, psychological and

physical state and influence of environment.

However it may be treated as a tool allowing for

exercising children’s concentration.

The research on gaze tracker carried out at the

MSD directs to increase its usability in other

applications in which the attention/concentration

assessment is needed.

ACKNOWLEDGEMENTS

The research work is partially supported by the

Polish Ministry of Science and Higher Education

within the project entitled: „Elaboration of a series

of computer multimodal interfaces and their

implementation to education, medicine, defence and

to industry" (POIG 1.3).

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Andrande L.C.V., Carvalho L.A.V., Lima C., 2006.

Supermarket Game: An Adaptive Intelligent Computer

Game for Attention Deficit/Hyperactivity Disorder

Diagnosis, Proceedings of the 5

Mexican

International Conference on Artificial Intelligence.

BM, website of the Brain Metrix, last access: 2008-11-17,

http://www.brainmetrix.com/concentration.htm

Czyzewski A., Kunka B., Kurkowski M., Branchat R.,

2008. Comparison of developed gaze point estimation

methods, Conference on New Trends in Audio and

Video. NTAV/SPA 2008.

DM, website of the Datamation, last access: 2008-11-17,

http://itmanagement.earthweb.com/

Pivec M., Trummer Ch., Pripfl J., 2006. Eye-Tracking

Adaptable e-Learning and Content Authoring Support,

University of Applied Sciences FH Joanneum.

UC, website of the Univ. of Cambridge,

last access: 2008-12-09

www.counselling.cam.ac.uk/concen.html

100%

50%

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