Table of Contents

1.      Application description.

2.      User’s Guide.

2.1         Setting parameters of the application.

2.1.1          “Name of testee”.

2.1.2          “Image of object”.

2.1.3          “Color”.

2.1.4          Other parameters.

2.1.5          Experimental scheme.

2.2         Recommendations.

2.3         Reading data.

3.      Practice of application.

3.1         Demonstration of spontaneous oscillations of body parts.

 

 

The application turns smartphones (tablets) into devices that evaluate the human movements accuracy at the moment and can be of interest those who play musical instruments, draw, dance, play sports, manages vehicles and so on. It could be just as useful in training others.

Since the application uses data generated by the accelerometer sensor, the application must be installed on devices that have such sensors. Also the device needs to run Android operating system v.4.2 or above.

The application is a test in the form of a game that consists of a repeating episode (attempt), determined by a set of parameters which you give at the beginning of the game. Below are the conditions recommended for this test as well as the recommendations on how to carry it out:

A single-color image of an object or a symbol (in psychophysics such an image is called a stimulus) on a homogeneous background of the same color tone, but of a different brightness is displayed on the device screen.

To change the brightness of the stimulus on the device screen the application uses the signal generated by the accelerometer when the position of the device changes. At the same time, the brightness of the background remains unchanged.

1. In each attempt from the moment it starts you must take the device in your hand and must tilt the device as much as it is necessary to achieve a coincidence of brightness of the stimulus and background that is, to merge the stimulus with the background and thus to achieve the disappearance of the image.
2. It should be noted that the deviation of the brightness depends not only on your ability to distinguish between brightness of the images. It also depends on the design of the screens of modern devices, which often leads to notable dependence of the brightness and color of the images on the angle between the surface of the screen and the direction of the your view. This dependence decreases if the direction of view is close to the perpendicular to the screen. The result of the test is characterized by two values: a score and a deviation of the brightness value. Score is a numerical estimate of the error of movement. The lower score corresponds to a more accurate movement. Deviation of the brightness is the average difference of the brightness of the stimulus from the brightness of the background during the test.
3. The accuracy of the hand movements depends on a condition of the nervous system, so normally the performance of hand movements characterizes the general performance of the nervous system. This connection between the quality of a small motility and the condition of the brain has been well-known for a long time.
4. Special software presented on the market allows transferring of the image of the device screen to a computer screen. Using this opportunity, you can get a direct evaluation of the movement quality of some part of the body by fixing the smartphone on this part of body and guided during the test by the image on the computer screen.
5. The measurements of the human activity performed by this application were developed by prof. V.A. Antonets and his coworkers in psychological and medical research. They were originally carried out with the help of an original ultrasound device called handtracker. The progress of information technologies in the recent years has made such measurements available to many people.

 

2.1 Setting parameters of the application.

Before beginning a test, the following settings must be set:

2.1.1 “Name of testee”.

Default value of this setting is “Name of device”, contained in the default list of names.

To change the name to some other name from the list - tap on the “names” window and select a name from the list.

To enter a new name into the list of names - tap on the "+" button located in the upper right corner of the screen, then tap the "new name" field to call the keyboard and type in a name.

2.1.2 “Image of object”.

Touch the field under “+” to choose an image of the object from the existing set: apple, square, dog, mouse, etc. displayed on the tab. This image will be used as a stimulus.

2.1.3 “Color”.

Choose a color from the list: gray, red, green, blue, red + green, red + blue, green + blue. Just like they do in sports, it is recommended to choose a color, using which you get the best results.

2.1.4 Other parameters.

The values of the following numerical parameters must be selected from the menu:

1. background brightness;
2. the brightness difference at the beginning of the attempt series (the value of the difference between the stimulus brightness and the background brightness);
3. duration of the attempt in seconds;
4. the number of attempts in the test series;
5. sensitivity (determines the connection of the stimulus brightness with the tilt angle of the device)

2.1.5 Experimental scheme.

Tilting the smartphone you need to achieve the disappearance of the image.

2.2 Recommendations.

1. In case of a training or demonstration measurements you can choose any settings of the brightness difference. In case of a test please set it on 0.
2. During the test, the device should be in a hand (in hands) and its center should be located at the upper part of a stomach, on the vertical midline of the body. The hands holding the device should not touch other parts of the body.
3. At the beginning of each attempt in a series the device should be in a horizontal position. It should be done during the pauses between attempts. Your head should be inclined so that gaze is directed approximately perpendicular to the device screen.
4. You have to tilt the device smoothly towards yourself or away from yourself, attempting to merge the stimulus with the background.
5. Before beginning the exercise make sure that the your eyes and the device's screen aren't exposed to bright light sources: windows, lamps, mirrors etc.
6. Different people perceive colors differently, and different smartphones and tablets reproduce these colors differently. Therefore after using with the application with the most comfortable setting of color, it is necessary to perform some additional work to obtain the most accurate results in the future. Namely: after testing with each of the colors offered by the application, use the one that allows you to get the minimum deviation value.
7. Choose from the stimuli offered by the application which personally appeals to you the most.

2.3 Reading data.

Primary output data represents values of the brightness difference, measured with a constant frequency of 30 times a second for each attempt.

For viewing of results of the tests - open the homepage of the application and choose a name from the list.

Then tap "Results" and you will see the list of folders named by the dates of testing.

Once you pick the date you will see the folders named by the time of the test as well as the name of the color of the stimulus and background. The results of each test are presented in the following form:

Here for each attempt from the series, the following data are shown:

• The graph of the brightness difference as function of time.
• The brightness deviation average for this attempt (equal to zero in case of an ideal control)
• The score, i.e. estimation of the of movements error in points.
• Histogram of the brightness difference in percents which was observed in the test: the numbers located lower the histogram columns are equal to values of the brightness differences observed during attempt and the number located above the column is equal to the percentage of the time when the brightness difference was equal to the number located lower the column. In the case of the ideal control, the histogram consists of a single column 100% high.

 

For the conscious use of the proposed tool, it is useful to perform the following simple experiments.

3.1 Demonstration of spontaneous oscillations of body parts.

These oscillations are necessary to enable awareness of location of mobile parts of a person’s body: fingers, hands, legs, head. In the normal state, a person doesn't notice oscillations of his body parts.

The amplitude of oscillations can increase considerably in case of a fatigue, stress and some disorders. In these cases, the oscillations may become visible to the naked eye.

To observe the oscillations of the hands using the application, you need to:

• take the device in hand (in hands), start the application and wait for the end of attempt without changing the position of the hand (hands).
• get acquainted with results of measurements.