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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Gaze control ability of League of Legends players in various game situations: Perspectives from solo-ranked match</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Inhyeok Jeong</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Donghyun Kim</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Naotsugu Kaneko</string-name>
          <email>kaneko@idaten.c.u-</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kimitaka Nakazawa</string-name>
          <email>nakazawa@idaten.c.u-tokyo.ac.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>8th International GamiFIN Conference 2024</institution>
          ,
          <addr-line>GamiFIN 2024</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>MaxForm Corp.</institution>
          ,
          <addr-line>242, Gonghang-daero, Gangseo-gu, 07805 Seoul</addr-line>
          ,
          <country>Republic of Korea</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>The University of Tokyo</institution>
          ,
          <addr-line>3-8-1, Komaba, Meguro-ku, 153-8902 Tokyo</addr-line>
          ,
          <country country="JP">Japan</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Previous research analyzes the superior gaze control ability of esports players in simple cognitive tasks or in full games. Therefore, it is necessary to understand the gaze control ability of esports players in various situations. We assumed that game situations that require multiple tasks had wider gaze distribution than other situations. Therefore, the current study aims to compare the gaze control ability between high- and middle-skilled "League of Legends (LoL)" players and among various game situations classified into four categories and in an unclassified situation (five in total). Eight high-skilled (top 10%) and eight middle-skilled (lower than the top 10%) LoL players were recruited for the experiment. They wore an eye tracker and were asked to play solo-rank matches in LoL games. We analyzed gaze distribution, Region of Interest (ROI), and fixation duration during the games. The results showed that high-skilled players had a wider gaze distribution and shorter fixation time regardless of the game scene than middle-skilled players. Furthermore, high-skilled players checked the ROI area more frequently than middle-skilled players, where they could see the overall flow and feedback of the game. Thus, focusing on the overall flow and feedback with wide gaze distribution is the source of high performance in LoL players. When the game situations required focusing on multiple stimulations simultaneously, wide gaze distribution was observed rather than in other situations, regardless of the skill level. Our results suggest that it is necessary to adopt the appropriate gaze control training for esports players based on the various situations in esports.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Gaze control ability</kwd>
        <kwd>League of Legends</kwd>
        <kwd>1solo-rank game</kwd>
        <kwd>esports</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Esports consists of competitive video games with
online and offline spectators [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. With the
development of the esports industry, research on
esports has also increased in various fields. From the
point of view of cognitive science, it is known that
esports can help players gain faster reaction time and
information processing skills [
        <xref ref-type="bibr" rid="ref2 ref3">2, 3</xref>
        ]. Moreover, esports
experts have superior visual behavior (e.g., gaze
movement) and attention skills (e.g., visual attention) [
        <xref ref-type="bibr" rid="ref4 ref5">4,
5</xref>
        ]. The gaze movement is a well-known factor for
understanding the superior performance level in
esports [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Among the many esports genres, the
multiplayer online battle arena (MOBA) game is well
known to require a high level of gaze control ability
and cognitive functions [
        <xref ref-type="bibr" rid="ref7 ref8">7,8</xref>
        ]. In MOBA games, players
team up with other teammates to fight against opponents
      </p>
      <p>0000-0002-1343-7442 (A1, Inhyeok Jeong);
0009-0001-97102542 (A2, Donghyun Kim); 0000-0002-1587-9287 (A3, Naotsugu
Kaneko); 0000-0001-5483-8659 (A4, Kimitaka Nakazawa)
© 2024 Copyright for this paper by its authors. The use permitted under
Creative Commons License Attribution 4.0 International (CC BY 4.0).</p>
      <p>
        CEUR Workshop Proceedings (CEUR-WS.org)
with complex strategies [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The MOBA game generates
various situations, such as one-on-one matches, team
fighting, and communication with other players.
      </p>
      <p>
        League of Legends (LoL) is one of the most famous
esports belonging to the MOBA game, where players team
up with 5 teammates to fight against opponents. To
achieve high performance in LoL, wide gaze distribution
and short fixation time are important for collecting more
information during gameplay [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Moreover, in real-time
strategy (RTS) games with a similar gaming interface to
MOBA games, high-skilled RTS players had wider gaze
distribution with fast gaze movement than low-skilled
RTS game players [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Information and interfaces in
MOBA and RTS games are widely distributed across the
entire monitor. Therefore, fast and wide gaze movement
allows high-skilled RTS and MOBA game players to
collect more information faster than low-skilled game
players during the gameplay [
        <xref ref-type="bibr" rid="ref10 ref4">4,10</xref>
        ]. To sum up the
previous studies [
        <xref ref-type="bibr" rid="ref10 ref4">4,10</xref>
        ], it is uncontroversial that
highskilled MOBA and RTS game players have superior
gaze control abilities.
      </p>
      <p>However, LoL game players do not always have to pay
attention to all the information from the entire monitor. In
a game situation when players are engaged with multiple
opponents, it is important to focus on a single piece of
information. When strategizing the fight, it is important to
pay attention to various information for an effective battle
simultaneously. Each percentage of the situation was
dynamically changed throughout the game. To sum up,
situations that need to focus on multiple information and
single information exist at the same time in a single LoL
game match.</p>
      <p>
        Even though various game situations exist in LoL, the
criteria for dividing the game scene for scientific research
in LoL is still lacking. Furthermore, given that different
game situations exist in a single LoL game match, it is
necessary to reveal the situation-based gaze control
abilities of LoL players. In RTS games, gaze movement
training based on the game situation has been suggested
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Therefore, revealing the situation-based gaze ability
of skilled LoL players, one of the most famous MOBA
genre esports might contribute to developing a new
specific training method for LoL players.
      </p>
      <p>
        In the current study, we used solo rank games to
categorize the game scene and evaluate the gaze control
ability of LoL players. The rankings of participants
directly change based on wins and losses matches in LoL
solo rank games. This ranking system serves as an
important motivational factor for esports players [
        <xref ref-type="bibr" rid="ref11 ref12">11,12</xref>
        ].
Thus, requiring participants to play a solo-ranked game is
an effective approach to studying their ability in actual
game situations. To sum up, using the solo rank game is
suitable for investigating the gaze control ability of LoL
players in various situations of actual LoL matches.
      </p>
      <p>
        The purpose of the current study is to investigate
the gaze control ability of skilled LoL players in
challenging and motivating tasks adapted to various
game situations using a solo rank game of LoL. The
game scene was divided by the game situations in the
solo rank game of LoL. According to previous research,
esports players have a wide gaze distribution when
performing multiple tasks simultaneously [
        <xref ref-type="bibr" rid="ref10 ref4">4,10</xref>
        ].
Therefore, we set the two hypotheses. H-1) Game
situations that require multiple tasks have wider gaze
distribution than not require multiple tasks. H-2)
High-skilled players show wider gaze distribution than
middle-skilled players in game situations that require
them to perform multiple tasks simultaneously.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. Methods</title>
      <sec id="sec-2-1">
        <title>2.1. Participants</title>
        <p>
          Eight high-skilled and eight middle-skilled LoL players
were recruited for the experiment. The official rank of
the high-skilled players was over than platinum rank
(top 10%). Middle-skilled players were involved in
bronze, silver, and gold tiers (lower than the top 10%).
All participants self-reported that they had normal
vision with no gaming disorder. Table 1 shows specific
information about the participants. The experiment
was approved by the Human Research Ethics
Committee of The University of Tokyo (approval
number: 872).
The current study used a 27-inch 144 Hz refresh rate
monitor for the experiment (ASUSTek Computer Inc.,
Taiwan) and an eye tracker (Pupil-core, Pupil-Lab,
Haftungsbeschränkt, Berlin, Germany). Gaze
movement was recorded using Pupil-Core, open-source
software for Pupil-Core (Version 3.5.7). The eye tracker
had one video camera (60 Hz, 1920 x 1080 px) and two
eye cameras (200 Hz, 192 x 192 px) to record the
experimental environment and gaze movement,
respectively. The eye tracker had 0.06° accuracy with
calibration and 0.02° precision. The eye tracker used the
“dark pupil” detection method to analyze gaze movement.
The “dark pupil” detection method detects the edge of the
pupil for estimating the location of the gaze position. The
eye tracker (pupil-core) had a maximum 40-millisecond
delay in processing the gaze movement data (including
pupil image transport, formatting, detecting, and showing
the results) [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ]. Four surface markers were attached to
the corners of the monitor (Figure 1) to define the
monitor screen and calibrate the gaze position. With
calibration, the coordinates of the participant's gaze
position were represented as a number between 0 and
1. The participants used their own mouse and
keyboards for the experiment.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>2.3. Experimental procedures</title>
        <p>Before the experiment, participants wore the eye
tracker and calibrated the gaze position using the
Screen Marker Calibration method. The Screen Marker
Calibration method calibrates the gaze position
through five dots that appear on the screen (one center
and four corners of the monitor) (Figure 2).</p>
        <p>When the calibration was finished, participants
logged in to their own LoL account for a solo-rank
match. Before starting the task, we set the distance
between the monitor and the head position of the
participants as 100 cm. After setting the head position, we
requested the participants to keep their current head
position as same as possible during the task. During the
experiment, participants freely played the solo-rank match
(called the Assignment). Solo-rank match was designed
by the publisher of LoL (Riot Games, Inc., California,
USA). During the solo-rank match, participants teamed up
with four random players to play the match (one team with
five members). When teaming up with four random
players, it will be matched with players who have similar
rankings to the participants by the AI matching system.
Participants fought against the other opponent team
players (not a bot) who had similar ranks to them.</p>
        <p>When the match was finished, gaze movement was
analyzed by open-source software for Pupil-Players
(version 3.5.7). The overall flow of the experiment can
be checked in Figure 3.</p>
      </sec>
      <sec id="sec-2-3">
        <title>2.4. The Assignment</title>
        <p>
          The game scene in the Assignment was divided into
four categories (Moving, Fighting, Object, and
Watching) and non-divided scene (ALL; total 5 game
scenes). In esports, the game scene was classified
based on the game situation that commonly appeared
during the gameplay [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ]. Thus, we categorized the
game scenes that commonly appeared during the LoL
single-rank matches as previous research. During the
experiment, we record the feature of the Assignment
as a video .mp4 file without including the gaze
movement data. After the experiment, a video file of
the Assignment was provided for an anonymous LoL
player who judged and divided the game scenes. The
game scene was classified by the top 1% of the ranked
anonymous LoL players with more than 10 years of
experience. In the Moving scene, the participant only
moves their character in the game (Figure 4A).
        </p>
        <p>Participants could move their characters by using the
mouse right-click. In the Fighting scene, the participant
freely fought with enemy team players by combining
the mouse left click and keyboard q, w, e, and r keys
(Figure 4B). Four different types of fighting scenes
were included in the Fighting scene (Figure 4B-1, 2, 3,
and 4). In the Object scene (Figure 4C), participants
fought with six types of objects that were operated by
a computer AI system (Tower, Nexus, Dragon,
Inhibitor, Rift Herald, and Baron). Participants can
obtain items and buffs that are important in the game
by defeating the six types of objects. Participants could
destroy the objects by using the mouse left click and
keyboard q, w, e, r keys. The Watching scene included
the action of watching another player play to check the
overall flow of the match by using the keyboard's left,
right, up, and down keys or mouse right-click (Figure
4D). Finally, the ALL scene was defined as a game scene
that was non-classified. The Assignment was finished
when the participants won or lost.</p>
        <p>After the Assignment was finished, two parameters
were calculated to evaluate the performance level. The
first is the Kill/Death/Assistant ratio (KDA) used to
evaluate the performance level of each participant.
KDA was calculated as following equation (1).

 ℎ</p>
        <p>+ 

 
(1)</p>
        <p>The second is “Total Damage to Champions” used
to evaluate the Assignment performance. "Total
Damage to Champions" represents the amount of
direct damage to the opponent team characters.</p>
      </sec>
      <sec id="sec-2-4">
        <title>2.5. Gaze movement acquisition</title>
        <p>
          At the end of the Assignment, gaze distribution, Region
of Interest (ROI), and fixation duration were calculated
for each of the five scenes (Moving, Fighting, Object,
Watching, and ALL scene). According to the
manufacturer, it is recommended to only use data with
a confidence level of 80% [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ]. The confidence level
was used as the accuracy of the gaze movement data.
The confidence level was calculated by the accuracy of
the pupil detected through the eye camera. A total of
7.18% of the gaze movement data (have lower
accuracy than 80%) were excluded from the
evaluation. In gaze distribution, the standard deviation
of horizontal and vertical gaze was calculated
respectively. The coordination of gaze position was
normalized by the monitor size and represented as a
number between 0 to 1. We set the five following ROIs:
Chatting, Skill, KDA, Mini-map, and Game scene areas
(Figure 5). Participants could view the chat in the
Chatting area (Figure 5A). In the Skill area, participants
could see the remaining time of skill, purchased items,
virtual commodity, and level of skills (Figure 5B). The
KDA area showed how many enemies a participant had
taken down and helped other teammates (Figure 5C).
In the Mini-map area, participants could see the entire
flow of the game (Figure 5D). The Game scene area
represents the main screen where the Assignment was
performed (Figure 5E). The percentage of gaze
position located in each ROI was calculated. Fixation
was defined when the gaze position was fixed more
than 100ms and the maximum pupil dispersion was
less than 1.5 degrees.
        </p>
      </sec>
      <sec id="sec-2-5">
        <title>2.6. Statistical analysis</title>
        <p>
          All statistical analyses were performed by the RStudio
version 4.3.1 (R Studio, Boston, MA, USA). After the
experiment, a power analysis was conducted to
estimate the number of participants was appropriate
(G*Power version 3.1.9). Three parameters were used
to estimate the power of the sample size. Horizontal
gaze distribution in the Moving scene and the
Watching scene, ROI percentage between high- and
middle-skill in the Mini-map area, and fixation
duration between high- and middle-skill were used for
power analysis. The effect size was calculated
according to Cohen’s method [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]. The specific results
of the power analysis can be checked in Table 2.
        </p>
        <p>
          According to Levene’s test and Shapiro-Wilk test,
all datasets did not follow the normality and
homogeneity. Therefore, the Wilcoxon rank-sum test
was performed to determine the difference in
performance levels (KDA and “Total Damage to
Champions) and experienced years between the
groups (high- and middle-skilled players). Gaze
movements (horizontal gaze distribution, vertical gaze
distribution, ROI, and fixation duration) were analyzed
by two-way analysis of variance (ANOVA) with aligned
rank transform (ART), non-parametric statistical
methods [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ], for two skill levels (high-skilled,
middleskilled) and five scenes (Moving, Fighting, Object,
Watching, ALL scenes). When a main effect was
observed in scenes, a contrast test was performed for
multiple comparisons. When a significant interaction
between skill level and scenes was observed, the
contrast test was performed as the post-hoc test. P
values were adjusted by using the Holm-Bonferroni
correction method. Partial η2 indicated effect size for
the ANOVA. All levels of statistical significance were
set at p &lt; .05.
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Results</title>
      <sec id="sec-3-1">
        <title>3.1. Scene classification result</title>
        <p>There was no significant difference between high- and
middle-skilled players in Assignment playtime
(highskilled: 1790 sec. ± 328 sec., middle-skilled: 1479.4
sec. ± 626 sec.; Wilcoxon rank-sum test, W = 17, p =
.42). A total of 1214 scenes were classified from all
participant’s game scenes (Moving: 358, Fighting: 419,
Object: 265, Watching: 172). There was no significant
main effect observed in skill level (F = 0.08, p = .77,
Partial η2 = .008). The main effect was detected in the
scene (F = 3.54, p = .02, Partial η2 = .31). According to
the contrast test, the Watching scene had a smaller
number than the Fighting scene (p = .03). However,
there was no significant difference in other scene
compare results (Moving-Fighting: p = .97;
MovingObject: p = .22; Moving-Watching: p = .09;
ObjectFighting: p = .10; Watching-Object: p = .96). There was
no interaction effect detected between skill level and
scene (F = 0.49, p = .73, Partial η2 = .01).</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Performance level</title>
        <p>The high-skilled players had a longer LoL experience
than the middle-skilled players (Wilcoxon rank-sum
test, W = 53.5, p = .02). Figure 6 indicates the
performance level of each group. The high-skilled
players had a significantly higher KDA than the
middle-skilled players (Wilcoxon rank-sum test, W =
52, p = .04). Moreover, the high-skilled players had
better “Total Damage to Champions” scores on average
(high-skilled players: 21567 ± 5328.6, middle-skilled
players: 14338.8 ± 14320.2, respectively). However,
there was no significant difference in “Total Damage to
Champions” scores between the high- and
middleskilled players (W = 48, p = .10).</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3. Gaze distribution</title>
        <p>3.4. ROIs
Figure 8 represents the percentage of gaze movement
in each ROI. Two-way ANOVA with ART revealed no
significant main effects (skill level: F = 0.20, p = .65,
Partial η2 = .006; scene: F = 1.94, p = .11, Partial η2 =
.08) and interaction (F = 0.29, p = .88, Partial η2 = .03)
in the Chatting area. In the Skill area, no significant
main effect (skill level: F = 0.11, p = .73, Partial η2 = .03;
scene: F = 0.18, p = .94, Partial η2 = .01) and interaction
(F = 0.17, p = .95, Partial η2 = .004) was detected. In the
KDA area, no significant main effect (skill level: F =
0.06, p = .79, Partial η2 = .001; scene: F = 0.30, p = .87,
Partial η2 = .04) and interaction (F = 0.20, p = .93,
Partial η2 = .04) was observed. In the Mini-map area,
the main effect was detected between high- and
middle-skilled players (F = 23.23, p &lt; .001, Partial η2 =
.23), but not in scene (F = 0.40, p = .80, Partial η2 = .01).
No interaction was detected in Mini-map area (F =
1.11, p = .35, Partial η2 = .02). There was no main effect
(skill level: F = 0.44, p = .50, Partial η2 = .01; scene: F =
0.33, p = .85, Partial η2 = .003) and interaction (F = 0.29,
p = .87, Partial η2 = .004) in the Game scene area.</p>
      </sec>
      <sec id="sec-3-4">
        <title>3.5. Fixation duration</title>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Discussion</title>
      <p>In the current study, we investigated the differences
between high- and middle-skilled players' gaze
movements depending on the situation. The
Assignment of the current study (solo-rank game) had
participants fight against opponent players in a
motivated situation (affecting the participant’s official
ranking). Moreover, participants fought against the
human opponent players. The motivated situation and
human opponent players allow the experiment to
reveal the source of the high performance of LoL
players in actual game situations. In terms of
performance level (KDA and Total Damage to
Champions), the high-skilled players had significantly
higher performance levels (KDA) than the
middleskilled players (Figure 6A). Moreover, the high-skilled
players had more experienced years than the
middleskilled players. This result indicates that each group
(high- and middle-skilled players) was clearly divided,
and high-skilled players had higher performance
levels than middle-skilled players. However, there was
no significant difference observed in Total Damage to
Champions between the groups. Total Damage to
Champions is affected by not only the individual
performance but also the items and positions that
participants used. For example, if participants select
the item and position to help the teammate rather than
directly fight with enemy players, Total Damage to
Champions is naturally decreased.</p>
      <p>According to the scene classification result (Result
3.1.), there was no significant difference in the number
of each scene between high- and middle-skilled
players. In addition, the number of the Fighting scene
was greater than the Watching scene. Thus, analyzing
the characteristics of the gaze movement as a whole
game without categorizing the situation is likely to bias
the overall results due to factors related to the specific
situations.</p>
      <p>
        According to the results about horizontal and
vertical gaze distribution, the high-skilled players had
a horizontally wider gaze distribution than the
middleskilled players (Figure 7A). It is well known that
dividing the gaze movement into horizontal and
vertical directions was common practice in esports
studies [
        <xref ref-type="bibr" rid="ref10 ref4 ref8">4,8,10</xref>
        ]. Moreover, previous research points
out that gaze distribution and performance level in
esports have significant correlations [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. Thus,
analyzing the gaze movement of esports players by
dividing the gaze distribution helps to understand the
superior gaze control ability of LoL players. Since the
monitor is a long object in the horizontal direction, no
significant difference between high- and
middleskilled players was caused by the physically short
length in the vertical direction. Moreover, the
highskilled players had a shorter fixation duration than the
middle-skilled players (Figure 9A). These results are
consistent with previous studies that have shown that
skilled LoL and real-time strategy (RTS) game players
had wider gaze distributions and short fixation times
[
        <xref ref-type="bibr" rid="ref10 ref4">4,10</xref>
        ].
      </p>
      <p>
        Horizontally wide gaze distributions might be
caused by the superior visual processing skills of
highskilled LoL players. Generally, the wide gaze
distribution is beneficial for collecting information
from a wide area in cognitive tasks and esports
[
        <xref ref-type="bibr" rid="ref10 ref17 ref18 ref4">4,10,17,18</xref>
        ]. Since the user interface and information
in LoL are widely spread on the monitor, it is essential
to check the entire screen for the information that LoL
players need. Obtaining information not only from a
wide area but also quickly is important for achieving
high visual processing skills. For example, short
fixation time with high task accuracy in cognitive tasks
represents high visual processing skills [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. In
fixation duration, high-skilled LoL players had a
shorter fixation duration than middle-skilled LoL
players regardless of the game scene. This indicates
that getting information quickly, regardless of the
game situation, might be a superior characteristic of
high-skilled LoL players. To sum up, short fixation time
and horizontally wide gaze distribution indicate that
high-skilled LoL players had superior visual
processing skills than middle-skilled players.
      </p>
      <p>
        Surprisingly, horizontal gaze distribution changed
significantly depending on the game situation
regardless of the skill level (Figure 7B; H-2). However,
there was no significant difference between high- and
middle-skilled LoL player’s gaze movements in specific
scenes (H-1). The results related to H-1 show that LoL
players should be able to control their gaze
movements for specific situations, regardless of their
skill level. The Moving scene had a wider horizontal
gaze distribution than the Fighting and Object scene.
Participants must move their characters after
understanding the overall flow to win the game. To
process the visual stimulation, it is necessary to
visually check the target first [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. Thus, it is beneficial
for winning the game to distribute the gaze movement
and gathers a broader range of information than in the
Fighting and Object scene through the wide gaze
movement. Fighting scenes and Object scenes have a
narrower distribution of gaze than Watching and ALL
scenes since more information is concentrated in the
center of the monitor. Furthermore, the gaze control
ability observed throughout the game (ALL scene) is
not the same as that in the Fighting scene. Previous
research suggests training to widen the gaze
distribution simply since skilled esports players have
a wider gaze distribution during games [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. However,
according to the result of the current study, it is
necessary to conduct situation-based gaze control
training in LoL players regardless of their skill level.
      </p>
      <p>
        In the ROI percentage of gaze position, high-skilled
players had a higher ROI percentage in the Mini-map
area than middle-skilled players for two reasons
(Figure 8G). First, the game interface is designed to
share the information in the Mini-map area. For
example, participants were able to give feedback on
dangers (e.g., enemy is coming) with icons in the
Minimap area. Second, the overall flow of the Assignment
was represented in the Mini-map area. Understanding
the overall flow of the game and cooperating with
teammates are key factors to winning. According to
previous research about RTS game players,
highskilled RTS game players frequently check the overall
flow of the games than low-skilled players [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. RTS
game and LoL had similar user interfaces (e.g., the
mini-map was represented in the right corner of the
monitor). Thus, focusing the gaze position on the
information about feedback and the overall flow might
be important factors in achieving the high
performance of the high-skilled players in LoL.
      </p>
      <p>However, there was no significant difference in the
ROI percentage of Skill and KDA area between
highand middle-skilled LoL players (Figure 8C and E).
There is a possibility that both high- and
middleskilled players had superior visuo-spatial ability. The
visuospatial ability is the capacity to memorize and
understand visual-spatial objects correctly [21]. Both
information in the Skill area and KDA area were
related to the visual and spatial elements. In the Skill
area, participants could check the left time of the skills.
In the KDA area, participants could see the information
about time and KDA. Previous research points out that
long-term esports training can improve visuospatial
ability [22]. In the current research, all participants
had enough LoL experience (experienced years;
highskilled: 9.2 years, middle-skilled: 4.3 years). Thus, it
might be able to estimate the information without
seeing the Skill and KDA area with high visuospatial
ability. Thus, each participant had enough experience
to guess what was being displayed without looking
directly at the information on the Skill and KDA area.</p>
      <p>In the Chatting area, there was no significant
difference between high- and middle-skilled players
detected in ROI percentage. The reason is as follows:
Both high- and middle-skilled players did not prefer to
use the Chatting area because typing the chatting takes
a long time to communicate with other players. It is
important to reduce wasting time to react fast during
the game. Therefore, there is a possibility that
participants spent less time communicating with other
players by using the feedback icons rather than typing
a chatting.</p>
      <p>The Game scene area is the main area where the
game is played. Therefore, the Game scene area had a
high importance in both high- and middle-skilled
players. High importance might be effect to no
significant difference in the Game scene area was
observed between high- and middle-skilled players.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Limitation</title>
      <p>In the current study, we only experimented with
eight high-skilled and eight middle-skilled LoL players
(small sample size). Thus, some parameters have low
power which is related to sample size (see Table 2). It
is important to be cautious about applying the
obtained results to all LoL players. In future research,
conducting the experiment with a large sample size is
necessary. To induce the actual solo-rank gameplay
situations, we did not strictly control the trial of each
scene. Thus, there is a possibility that some scenes
might have more or fewer gaze points and affect the
gaze movement-related data. Moreover, we did not
strictly control the head movement. Therefore, we
cannot exclude the possibility that head movement
affected the gaze movement data.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion</title>
      <p>The current study analyzed the gaze control ability
of esports players in various and motivated situations.
High-skilled LoL players were advantageous to collect
the information from a wide area through a wider gaze
distribution and a shorter gaze fixation time than
middle-skilled players regardless of the game situation.
Since overall flow and communication information had
an essential role in achieving high performance,
highskilled players saw the area displaying overall flow
and communication information than middle-skilled
players. Surprisingly, the gaze control abilities showed
significant differences between full games and specific
situations, regardless of skill level. Specifically, gaze
distribution was wider in game situations, which
require focusing on multiple pieces of information
simultaneously, than in other situations. Therefore,
esports research should investigate the gaze control
ability of esports players in separate game situations
might shed light on the development of the training
method in esports.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgments</title>
      <p>We appreciate Minjun Kim for providing information
on LoL-related knowledge. The current research was
supported by the Tateisi Science and Technology
Foundation (grant number: 2237004), Meiji Yasuda
Life Foundation of Health and Welfare.
[21] F. Irani, “Visual-Spatial Ability BT - Encyclopedia
of Clinical Neuropsychology,” J. S. Kreutzer, J.
DeLuca, and B. Caplan, Eds. New York, NY:
Springer New York, 2011, pp. 2652–2654.
[22] L. Milani, S. Grumi, and P. Di Blasio, “Positive
Effects of Videogame Use on Visuospatial
Competencies: The Impact of Visualization Style
in Preadolescents and Adolescents,” Front.
Psychol., vol. 10, 2019, doi:
10.3389/fpsyg.2019.01226.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>V. H. S. E.</given-names>
            <surname>Robertson</surname>
          </string-name>
          , “eSports and
          <string-name>
            <given-names>Digital</given-names>
            <surname>Ecosystems</surname>
          </string-name>
          :
          <article-title>An Antitrust Perspective,”</article-title>
          <string-name>
            <given-names>J. Eur. Compet. Law</given-names>
            <surname>Pract</surname>
          </string-name>
          ., vol.
          <volume>12</volume>
          , no.
          <issue>8</issue>
          , pp.
          <fpage>591</fpage>
          -
          <lpage>592</lpage>
          , Oct.
          <year>2021</year>
          , doi: 10.1093/jeclap/lpab040.
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>J. G.</given-names>
            <surname>Reitman</surname>
          </string-name>
          ,
          <string-name>
            <surname>M. J. Anderson-Coto</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          <string-name>
            <surname>Wu</surname>
            ,
            <given-names>J. S.</given-names>
          </string-name>
          <string-name>
            <surname>Lee</surname>
            , and
            <given-names>C.</given-names>
          </string-name>
          <string-name>
            <surname>Steinkuehler</surname>
          </string-name>
          , “Esports Research: A Literature Review,” Games Cult., vol.
          <volume>15</volume>
          , no.
          <issue>1</issue>
          , pp.
          <fpage>32</fpage>
          -
          <lpage>50</lpage>
          ,
          <year>2020</year>
          , doi: 10.1177/1555412019840892.
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>M. W. G.</given-names>
            <surname>Dye</surname>
          </string-name>
          ,
          <string-name>
            <given-names>C. S.</given-names>
            <surname>Green</surname>
          </string-name>
          , and
          <string-name>
            <given-names>D.</given-names>
            <surname>Bavelier</surname>
          </string-name>
          , “
          <source>Increasing Speed of Processing With Action Video Games,” Curr. Dir. Psychol. Sci.</source>
          , vol.
          <volume>18</volume>
          , no.
          <issue>6</issue>
          , pp.
          <fpage>321</fpage>
          -
          <lpage>326</lpage>
          , Dec.
          <year>2009</year>
          , doi: 10.1111/j.1467-
          <fpage>8721</fpage>
          .
          <year>2009</year>
          .
          <volume>01660</volume>
          .x.
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>J.</given-names>
            <surname>Inhyeok</surname>
          </string-name>
          ,
          <string-name>
            <given-names>K.</given-names>
            <surname>Nakagawa</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R.</given-names>
            <surname>Osu</surname>
          </string-name>
          , and
          <string-name>
            <given-names>K.</given-names>
            <surname>Kanosue</surname>
          </string-name>
          , “
          <article-title>Difference in gaze control ability between low and high skill players of a real-time strategy game in esports,” PLOS ONE</article-title>
          . pp.
          <fpage>1</fpage>
          -
          <lpage>17</lpage>
          ,
          <year>2022</year>
          , doi: 10.1371/journal.pone.
          <volume>0265526</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>W. R.</given-names>
            <surname>Boot</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A. F.</given-names>
            <surname>Kramer</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D. J.</given-names>
            <surname>Simons</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Fabiani</surname>
          </string-name>
          , and G. Gratton, “
          <article-title>The effects of video game playing on attention, memory, and executive control,” Acta</article-title>
          <string-name>
            <surname>Psychol.</surname>
          </string-name>
          (Amst)., vol.
          <volume>129</volume>
          , no.
          <issue>3</issue>
          , pp.
          <fpage>387</fpage>
          -
          <lpage>398</lpage>
          ,
          <year>2008</year>
          , doi: 10.1016/j.actpsy.
          <year>2008</year>
          .
          <volume>09</volume>
          .005.
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>A.</given-names>
            <surname>Klostermann</surname>
          </string-name>
          ,
          <string-name>
            <given-names>C.</given-names>
            <surname>Vater</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R.</given-names>
            <surname>Kredel</surname>
          </string-name>
          , and E.-J. Hossner, “Perception and Action in Sports.
          <source>On the Functionality of Foveal and Peripheral Vision</source>
          ,” Front.
          <source>Sport. Act. Living</source>
          , vol.
          <volume>1</volume>
          ,
          <year>2020</year>
          , doi: 10.3389/fspor.
          <year>2019</year>
          .
          <volume>00066</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>X.</given-names>
            <surname>Li</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Huang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Li</surname>
          </string-name>
          ,
          <string-name>
            <given-names>H.</given-names>
            <surname>Wang</surname>
          </string-name>
          , and C. Han, “
          <article-title>Time for a true display of skill: Top players in League of Legends have better executive control,” Acta</article-title>
          <string-name>
            <surname>Psychol.</surname>
          </string-name>
          (Amst)., vol.
          <volume>204</volume>
          , p.
          <fpage>103007</fpage>
          ,
          <year>2020</year>
          , doi: https://doi.org/10.1016/j.actpsy.
          <year>2020</year>
          .
          <volume>103007</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>F.</given-names>
            <surname>Ryousuke</surname>
          </string-name>
          , and
          <string-name>
            <given-names>H.</given-names>
            <surname>Goichi</surname>
          </string-name>
          , “
          <article-title>Gaze and Electroencephalography (EEG) Parameters in Esports: Examinations Considering Genres</article-title>
          and Skill Levels”,
          <source>2023 International Workshop on Smart Info-Media Systems in Asia (SISA</source>
          <year>2023</year>
          ),
          <source>Aug.31- Sep</source>
          .1.
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>M.</given-names>
            <surname>Mora-Cantallops and M.-Á</surname>
          </string-name>
          . Sicilia, “
          <article-title>MOBA games: A literature review</article-title>
          ,
          <source>” Entertain. Comput.</source>
          , vol.
          <volume>26</volume>
          , pp.
          <fpage>128</fpage>
          -
          <lpage>138</lpage>
          ,
          <year>2018</year>
          , doi: https://doi.org/10.1016/j.entcom.
          <year>2018</year>
          .
          <volume>02</volume>
          .005.
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <given-names>I.</given-names>
            <surname>Jeong</surname>
          </string-name>
          ,
          <string-name>
            <given-names>K.</given-names>
            <surname>Kudo</surname>
          </string-name>
          ,
          <string-name>
            <given-names>N.</given-names>
            <surname>Kaneko</surname>
          </string-name>
          , and
          <string-name>
            <given-names>K.</given-names>
            <surname>Nakazawa</surname>
          </string-name>
          , “
          <article-title>Esports experts have a wide gaze distribution and short gaze fixation duration: A focus on League of Legends players</article-title>
          ,”
          <source>PLoS One</source>
          , vol.
          <volume>19</volume>
          , no.
          <issue>1</issue>
          , p.
          <fpage>e0288770</fpage>
          ,
          <string-name>
            <surname>Jan</surname>
          </string-name>
          .
          <year>2024</year>
          , [Online], doi: https://doi.org/10.1371/journal.pone.
          <volume>0288770</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <given-names>D.</given-names>
            <surname>Railsback</surname>
          </string-name>
          and
          <string-name>
            <given-names>N.</given-names>
            <surname>Caporusso</surname>
          </string-name>
          , “
          <article-title>Investigating the Human Factors in eSports Performance BT - Advances in Human Factors in Wearable Technologies</article-title>
          and Game Design,”
          <year>2019</year>
          , pp.
          <fpage>325</fpage>
          -
          <lpage>334</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <given-names>F.</given-names>
            <surname>Brühlmann</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Baumgartner</surname>
          </string-name>
          , G. Wallner, and
          <string-name>
            <given-names>S.</given-names>
            <surname>Kriglstein</surname>
          </string-name>
          , “Motivational Profiling of League of Legends Players,” vol.
          <volume>11</volume>
          , no.
          <source>July</source>
          , pp.
          <fpage>1</fpage>
          -
          <lpage>18</lpage>
          ,
          <year>2020</year>
          , doi: 10.3389/fpsyg.
          <year>2020</year>
          .
          <volume>01307</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          [13]
          <string-name>
            <given-names>M.</given-names>
            <surname>Kassner</surname>
          </string-name>
          ,
          <string-name>
            <given-names>W.</given-names>
            <surname>Patera</surname>
          </string-name>
          ,
          <string-name>
            <surname>A</surname>
          </string-name>
          . Bulling , “
          <article-title>Pupil: An Open Source Platform for Pervasive Eye Tracking and Mobile Gaze-Based Interaction”</article-title>
          ,
          <source>Proceedings of the 2014 ACM International Joint Conference on Pervasive and Ubiquitous Computing: Adjunct Publication</source>
          ,
          <year>2014</year>
          ,
          <fpage>1151</fpage>
          -
          <lpage>1160</lpage>
          , doi: https://doi.org/10.1145/2638728.2641695.
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          [14]
          <string-name>
            <given-names>Y.</given-names>
            <surname>Maeda</surname>
          </string-name>
          , “
          <source>Scene Classification in FPS Game Videos Based on Acoustic Information.” 2023 IEEE Conference of Games</source>
          ,
          <year>2023</year>
          , ISBN:
          <fpage>9798350322774</fpage>
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          [15]
          <string-name>
            <given-names>J.</given-names>
            <surname>Cohen</surname>
          </string-name>
          ,
          <article-title>Statistical Power Analysis for the Behavioral Sciences</article-title>
          .
          <year>2013</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          [16]
          <string-name>
            <given-names>J. O.</given-names>
            <surname>Wobbrock</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Findlater</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Gergle</surname>
          </string-name>
          , and
          <string-name>
            <given-names>J. J.</given-names>
            <surname>Higgins</surname>
          </string-name>
          , “
          <article-title>The Aligned Rank Transform for Nonparametric Factorial Analyses Using Only Anova Procedures</article-title>
          ,”
          <source>in Proceedings of the SIGCHI Conference on Human Factors in Computing Systems</source>
          ,
          <year>2011</year>
          , pp.
          <fpage>143</fpage>
          -
          <lpage>146</lpage>
          , doi: 10.1145/1978942.1978963.
        </mixed-citation>
      </ref>
      <ref id="ref17">
        <mixed-citation>
          [17]
          <string-name>
            <given-names>I.</given-names>
            <surname>Jeong</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Nobuto</surname>
          </string-name>
          ,
          <string-name>
            <given-names>N.</given-names>
            <surname>Kaneko</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Kato</surname>
          </string-name>
          , and
          <string-name>
            <given-names>K.</given-names>
            <surname>Nakazawa</surname>
          </string-name>
          , “
          <article-title>Investigating the gaze control ability of VALORANT players using a Python based tool</article-title>
          ,” arXiv Prepr., doi: https://doi.org/10.48550/arXiv2310.15542,
          <year>2023</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref18">
        <mixed-citation>
          [18]
          <string-name>
            <given-names>M.</given-names>
            <surname>Sanz-matesanz</surname>
          </string-name>
          , G. M.
          <article-title>Gea-garcía, and</article-title>
          <string-name>
            <surname>L. M.</surname>
          </string-name>
          <article-title>Martínez-aranda, “Computers in Human Behavior Physical and psychological factors related to player ' s health and performance in esports : A scoping review</article-title>
          ,
          <source>” Comput. Human Behav</source>
          ., vol.
          <volume>143</volume>
          , no.
          <source>August</source>
          <year>2022</year>
          , p.
          <fpage>107698</fpage>
          ,
          <year>2023</year>
          , doi: 10.1016/j.chb.
          <year>2023</year>
          .
          <volume>107698</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref19">
        <mixed-citation>
          [19]
          <string-name>
            <given-names>S.</given-names>
            <surname>Pannasch</surname>
          </string-name>
          ,
          <string-name>
            <given-names>J.</given-names>
            <surname>Schulz</surname>
          </string-name>
          , and
          <string-name>
            <given-names>B. M.</given-names>
            <surname>Velichkovsky</surname>
          </string-name>
          , “
          <article-title>On the control of visual fixation durations in free viewing of complex images</article-title>
          ,” Attention, Perception, Psychophys., vol.
          <volume>73</volume>
          , no.
          <issue>4</issue>
          , pp.
          <fpage>1120</fpage>
          -
          <lpage>1132</lpage>
          ,
          <year>2011</year>
          , doi: 10.3758/s13414-011-0090-1.
        </mixed-citation>
      </ref>
      <ref id="ref20">
        <mixed-citation>
          [20]
          <string-name>
            <given-names>B. D.</given-names>
            <surname>Cameron</surname>
          </string-name>
          and
          <string-name>
            <given-names>J.</given-names>
            <surname>López-Moliner</surname>
          </string-name>
          , “
          <article-title>Target modality affects visually guided online control of reaching,” Vision Res</article-title>
          ., vol.
          <volume>110</volume>
          , pp.
          <fpage>233</fpage>
          -
          <lpage>243</lpage>
          ,
          <year>2015</year>
          , doi: https://doi.org/10.1016/j.visres.
          <year>2014</year>
          .
          <volume>06</volume>
          .010.
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>