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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Evaluation of Brain Attention Levels Using Arduino and Neurosky Mindwave EEG According to Age and Sex</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Susan Pari-Larico</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Brandon Llerena-Urday</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Álvaro Fernández del Carpio</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Karina Rosas-Paredes</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>José Esquicha-Tejada</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Faculty of Physical and Formal Sciences and Engineering, Universidad Catolica de Santa Maria</institution>
          ,
          <addr-line>04000</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>Attention is one of the main cognitive skills that is constantly used in everyday life. However, various factors can be diminished and even blocked by various disorders, diseases or behaviors that affect people's performance. To analyze the brain signals, the Neurosky MindWave EEG device is required, this device determines the levels of attention of people when they perform some activity and Arduino for data capture. This article compares data obtained from reading the level of care of people of different ages and sex using the Neurosky and Arduino Uno devices. The results obtained show that women (sex) and adults (age) have greater stability of attention over time, and that men (sex) and youth (age) get to obtain higher levels of attention.</p>
      </abstract>
      <kwd-group>
        <kwd>Attention</kwd>
        <kwd>brain signal</kwd>
        <kwd>neuronal sensor</kwd>
        <kwd>microcontroller</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>Attention is the basic cognitive skill in the life of every person regardless of age. Its
importance lies in the fact that thanks to these mental processes, both school, and
work performance tend to increase. This favors the development of other skills such
as imagination and creativity. This capacity generates greater confidence in ourselves
and improves our interpersonal relationships.</p>
      <p>
        Currently, problems of concentration in society have been increasing [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], however,
this deficit can be overcome with adequate training and motivation. Training our
attention capacity helps us to increase and improve our level of concentration and this
makes us much more productive people; athletes, for example, exercise these skills
and this allows them to improve their athletic performance [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        Currently, there are numerous projects and researches that make use of these devices.
For example, the Neurosky MindWave EEG, a device with neuronal sensors to
measure attention levels, has been used to interact with games[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], control a robot with
the mind[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], improve the concentration of children with autism[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], assess attention
levels in children [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], among others. On the other hand, the Arduino device, a plate
with a microcontroller that reads sensors and allows digital and interactive devices to
be built, has been used in education [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], in improving the quality of life of adults and
people with disabilities [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], in the development of a fire alarm system [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], and so on.
This research has as objective integrate two devices, the Arduino and the Neurosky
MindWave EEG to measure the level of attention of the person using it. The collected
data are stored in a spreadsheet, and in real-time a graph of lines is generated,
according to the concentration values, to obtain the patterns according to each profile.
This article shows in the second section the related works, in the third section the
applied methodology, in the fourth section it shows the development of the project
and the statistics obtained from different samples, the results and discussions are
presented in the fifth section, and finally the conclusions.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2 Related work</title>
      <p>
        Research works focused on identifying the level of attention have been of interest for
many researchers. Several training programs are used to enhance memory capabilities
in childrens. In [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], a type of sensors called “neurosky” is applied to analysis brain
waves. This device determines the attention levels when people are doing some
activity. The results present scores achieved by each person regarding attention and
meditation levels through a daily scanner using the WinWave device.
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], a device based on Brain Computer Interface (BCI) or also called
MindMachine Interface (MMI) was developed for instrumenting the meditation and
attention level of human brain. The mindwave mobile headset captures electrical signs
from the brain and identifies thoughts and emotional states, and also gives information
on the brainwave frequency bands. Results of experiments show differences of
attention between girls and boys when doing similar activities, but girls have higher
meditation level when solving problems.
      </p>
      <p>
        The Neurosky’s MindWave device is used in [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] for detecting attention levels when
studies do multiple readings. Some interesting results show that students presented
better attention levels when information is presented in the format of Power Point and
digital maps in real classroom activities.
      </p>
      <p>
        The alpha and beta waves in human brains generally determine the attention level, but
it can be affected when moods turn from normal to stress. These variations and their
effect on level attention is researched in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], also taking into account the age and sex.
Results demonstrated that with the normal mood a better concentration can be achieved
than with a stressed mood, and that girls generally show more attention level than the
boys.
      </p>
      <p>In conclusion, the measurement of the brain signs using different kind of devices have
as main goal identify the mental level in order to make corrective actions in restoring
the level attention. The researchers propose the use of Arduino together with similar
devices identified in the research works as a contribution to enhance the researches in
this area.</p>
    </sec>
    <sec id="sec-3">
      <title>Methodology</title>
      <p>The development of the proposal consists of 4 stages:
 Proposal design. - A design was made about the integration of the different
devices, to achieve the objective of obtaining the reading data of the different
people.
 Development of the proposal. - It consisted of programming the Arduino
microcontroller and configuring the Bluetooth HC 05 and the Neurosky MindWave
EEG.
 Tests of the proposal. - To test the proposal, the level of attention to different
persons of age and sex was read.
 Interpretation of results. -Through the data obtained, it was possible to rescue
patterns according to the profiles of people and establish comparisons with other
related research.</p>
    </sec>
    <sec id="sec-4">
      <title>4 Project Development</title>
      <p>To capture the data we used an Arduino Uno board, a Bluetooth HC-05 to connect
Arduino to MindWave, a 2X16 LCD screen, and 3 LEDs (red, yellow and green) that
will light up depending on the level of attention. The elements and actions carried out
in the project are described below:</p>
      <sec id="sec-4-1">
        <title>4.1 Connection LCD screen 2X16 I2C</title>
        <p>
          This is a device that allows the user's attention level values to be displayed when
using the MindWave [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ]. The connection of this device to the Arduino board is
shown in Table 1.
Sometimes, even if all pins are connected correctly, the display does not show
values. This is because the potentiometer of the device must be calibrated for its
intensity. To solve this problem, turn the potentiometer until the desired result is
obtained.
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2 Connection and configuration of Bluetooth module HC-05</title>
        <p>
          There are several models and versions of the HC-05 module. Its main feature is that
it has a push-button that will serve to enter AT Mode and then configure it. [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ].
The configuration of the Bluetooth module is described in the following steps:
Step 1: Connection. - The connection of the HC-05 to the Arduino board is
shown in Table 2.
Step 2: Enter AT mode. - After making the connection, you have to load a
sketch in Arduino. Before connecting the Arduino board to the computer, the
HC-05 pushbutton must be held down while connecting to the PC until the
Bluetooth module LED turns on and off intermittently, indicating that it is in AT
mode.
        </p>
        <p>Step 3: Configuration. - Once the previous step has been completed, the
Arduino serial is opened and the options "38400 baud" and "Both NL &amp; CR" are
changed. This will allow you to enter AT commands, which are shown in Fig. 1.
These commands allow you to configure the Bluetooth module to connect to the
MindWave.</p>
      </sec>
      <sec id="sec-4-3">
        <title>4.3 Integration of all devices</title>
        <p>Once the HC-05 and the LCD are connected and configured, 3 LEDs (red, yellow
and green) are added, as shown in the final diagram (see Fig. 2).</p>
      </sec>
      <sec id="sec-4-4">
        <title>4.4 Program Coding</title>
        <p>The code sketch included the LiquidCrystal_I2C.h and Wire.h libraries, this to
visualize the level of attention of the person through the LCD screen.</p>
        <p>The following code allows you to display the user's level of quality and attention on
the Arduino serial, as well as to display the level of attention on the LCD screen.</p>
        <sec id="sec-4-4-1">
          <title>Serial.print("PoorQuality: ");</title>
          <p>Serial.print(poorQuality, DEC);
Serial.print(" Attention: ");
Serial.print(attention, DEC);
/////////////////////////////
lcd.setCursor(0, 1);
lcd.print(attention);
lcd.print(" ");
/////////////////////////////
Serial.print(" Time since last packet: ");
Serial.print(millis() - lastReceivedPacket, DEC);
lastReceivedPacket = millis();</p>
          <p>Serial.print("\n");
Finally, care ranges were implemented, ranging from 0 to 100, with 0 to 40
considering a low level, 40 to 70 intermediate and 70 to 100 high. Depending on the
level of attention, the red, yellow and green LEDs will be illuminated accordingly (see
next code).</p>
          <p>if(attention &lt;40 &amp;&amp; attention &gt; 0)
{
}
digitalWrite(GREENLED1, LOW);
digitalWrite(YELLOWLED1, LOW);
digitalWrite(REDLED1, HIGH);
}
if(attention &lt;71 &amp;&amp; attention &gt; 39)
{
digitalWrite(GREENLED1, LOW);
digitalWrite(YELLOWLED1, HIGH);
digitalWrite(REDLED1, LOW);
}
if(attention &lt;101 &amp;&amp; attention &gt; 70)
{
digitalWrite(GREENLED1, HIGH);
digitalWrite(YELLOWLED1, LOW);
digitalWrite(REDLED1, LOW);</p>
        </sec>
      </sec>
      <sec id="sec-4-5">
        <title>4.5 Compilation of the experiment</title>
        <p>The steps to follow to compile the program are the following:
- Make sure that the connections are correctly located.
- Connect the Arduino board to the computer.
- Disconnect the RX from the Arduino board with the HC-05 TX.
- Compile the sketch.
- Open the serial with 57600 bauds.
- Place the MindWave on the head.
- Wait a few seconds and switch on the MindWave
- The Arduino board and the MindWave must be connected automatically (if this
is not the case, press upwards for 3 seconds until the headset light and the LED of
the Bluetooth module stop flashing).
- Reconnect the Arduino RX with the HC-05 TX.
- Check the variation of the LEDs concerning their level of attention.
- Observe the attention level on the LCD screen.</p>
        <p>
          The complete code can be located at [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
        </p>
      </sec>
      <sec id="sec-4-6">
        <title>4.6 Data capture in an Excel file</title>
        <p>
          The data capture was worked based on an excel sheet developed by [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ] that consists
of the reading of the incoming values by the serial port of the computer. This file
makes use of the library created by David M. Hitchner and adapted to work with 64
bits by Hal Evensen[
          <xref ref-type="bibr" rid="ref16">16</xref>
          ].
        </p>
        <p>The main modification to the file is in the code linked to the "Open Port" button (see
next code) since it was originally made to work with 9600 bauds, but as we remember,
our program works at 57600.</p>
        <sec id="sec-4-6-1">
          <title>Private Sub Open_Port_Click()</title>
          <p>Dim ID_Port As Integer ' Choice of port COM1 to COM4.
Dim State As Long 'Returns 0 if there have been no error
ID_Port = 3 ' COM3 port is established.
' The port is opened with the following characteristics.
' Retry action is not implemented.</p>
          <p>State = CommOpen(ID_Port, "COM" &amp; CStr(ID_Port), _
"baud=57600 parity=N data=8 stop=1")
With the addition of this file in the project, the sketch code shown above must be
modified so that only the value of the "attention" variable is displayed by the serial.
Afterward, just connect the Arduino to the computer (the previously compiled program
is already stored in the Arduino memory). You must select the button "Open Port" and
then "Read Port", and you will see how the values of the table and the graph are
modified by capturing the level of attention through the Mindwave.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5 Results and Discussion</title>
      <p>For this research, a level of care test was done on 46 people, of whom 20 were men
and 26 women; and in turn, xz is a common factor to which people are subjected, even
in their hours of study, at the end a test of compression of what they had read.</p>
      <sec id="sec-5-1">
        <title>5.1 Comparison of data by sex</title>
        <p>According to the data obtained (See Fig. 3a), it is appreciated that men reach higher
levels of attention, but over time these go down. On the other hand, although women
do not get high levels of attention, it remains more constant. A normal distribution was
observed for each group (Kolmogorov-Smirnov test: p&gt;0.05). The average value of
men is statistically significantly higher than the women’s value (t test, p&lt;0.05) (See
Fig. 3b)</p>
        <p>M en
x
e
S
W om en
40
60
A v e ra g e
80</p>
      </sec>
      <sec id="sec-5-2">
        <title>5.2 Comparison of data by age</title>
        <p>The results obtained are shown in (Fig. 4a). It can be seen that although the minors
were very enthusiastic about trying the experiment and could reach good levels of
attention, the values were very unstable. On the other hand, young people had the
possibility of having a higher level of attention, but these values decreased with time,
presenting a bit of instability. Finally, the values show that adults were the most stable
during the evaluation time. A normal distribution was observed in two groups (minors
and young people). Adult data had a non-normal distribution. The analysis showed
statistically significant differences between the groups (Kruskal-Wallis test, p&lt;0.05).
Young people have a higher average than the minors (p&lt;0.05). Adults have a higher
average than the minors (p&lt;0.05). No statistically significant differences were found
between adults and young people average (p&gt;0.05) (See Fig. 4b).
The results show that students lose attention levels over school hours, being similar to
the results in men and young adults people, who low their attention level over time.
When students are training to improve their attention, it comes with constant values.
The attention of the children when they read a book reaches an average of 51. Finally,
in the tests carried out, the existence of small-time ranges was appreciated where
people low their level of attention, maybe due to the emotion that can be transmitted
when reading a book.
6</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Conclusions</title>
      <p>The Arduino and Neurosky MindWave EEG allowed us, with a low cost, to carry out
an in-depth evaluation of how people's attention changes according to age or sex, this
required a spreadsheet that collects the samples sent by Arduino.</p>
      <p>The fundamental cognitive ability in the life of the human being is the attention, this
one favors the yield and personal development. This cognitive ability varies according
to the age or sex of the human being, as expressed in this research.</p>
      <p>Males tend to have high levels of attention compared to females, however, this
decreases over time. On the other hand, women's attention tends to remain constant.
Based on age, the level of attention in children often varies being unstable, young
people have a level of attention, but little by little this decreases. In contrast, adults
maintain a constant level of attention
With this research, you have the basis to perform various tests in different situations
that know if a human being is attentive, in future research you will have more detail to
develop new methodologies of how to improve education according to age and sex.</p>
      <sec id="sec-6-1">
        <title>Acknowledgments</title>
        <p>The authors express their gratitude to the Vice-rectorate of Research of the
Universidad Catolica de Santa María for the opportunity to develop this research using
Resolution 24710-R-2017.</p>
      </sec>
    </sec>
  </body>
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