NURS 502: Critique article : The Effect of Online Violent Video Games on Levels of Aggression

The Effect of Online Violent Video Games on Levels of Aggression Jack Hollingdale1*, Tobias Greitemeyer2

1 School of Psychology, University of Sussex, Brighton, United Kingdom, 2 Institute of Psychology, University of Innsbruck, Innsbruck, Austria

Abstract

Background: In recent years the video game industry has surpassed both the music and video industries in sales. Currently violent video games are among the most popular video games played by consumers, most specifically First-Person Shooters (FPS). Technological advancements in game play experience including the ability to play online has accounted for this increase in popularity. Previous research, utilising the General Aggression Model (GAM), has identified that violent video games increase levels of aggression. Little is known, however, as to the effect of playing a violent video game online.

Methods/Principal Findings: Participants (N = 101) were randomly assigned to one of four experimental conditions; neutral video game—offline, neutral video game—online, violent video game—offline and violent video game—online. Following this they completed questionnaires to assess their attitudes towards the game and engaged in a chilli sauce paradigm to measure behavioural aggression. The results identified that participants who played a violent video game exhibited more aggression than those who played a neutral video game. Furthermore, this main effect was not particularly pronounced when the game was played online.

Conclusions/Significance: These findings suggest that both playing violent video games online and offline compared to playing neutral video games increases aggression.

Citation: Hollingdale J, Greitemeyer T (2014) The Effect of Online Violent Video Games on Levels of Aggression. PLoS ONE 9(11): e111790. doi:10.1371/journal. pone.0111790

Editor: Cheryl McCormick, Brock University, Canada

Received August 5, 2014; Accepted September 21, 2014; Published November 12, 2014

Copyright: � 2014 Hollingdale, Greitemeyer. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. All relevant data are within the paper and its Supporting Information files.

Funding: This research was supported by grant P23809 from the Austrian Science Fund. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

* Email: [email protected]

Introduction

The video game industry is now the largest entertainment

industry in the UK. 2011 industry figures have identified that

game sales, including platform and digital, have exceeded both

music and video sales [1]. Violent video games have previously

been identified to be the most popular video games played by

consumers [2]. Research into the effect of violent video games on

levels of aggression has led to concerns that they may pose a public

health risk [3]. Indeed, cross-sectional studies have found positive

correlations between violent video game play and real-life

aggression [4–6]. Longitudinal studies showed that habitual

violent video game play predicts later aggression even after

controlling for initial levels of aggressiveness [7–9]. Finally,

experimental studies have revealed that playing violent video

games is a causal risk factor for increased aggression [10–12]. It

should be noted, however, that there is other research showing no

evidence that engagement with violent video games leads to

increases in aggression or reductions in prosocial behaviour [13–

16], warranting the need for further research in this area. On

balance however, evidence from meta-analyses confirm that

exposure to violent video games increases aggressive cognitions,

aggressive affect and aggressive behaviour, and decreases empathy

and prosocial behaviour [17,18].

Much of the research that has provided evidence to indicate the

negative effects of violent video games has utilised the General

Aggression Model (GAM) [19]. A widely accepted model for

understanding media effects, the GAM posits that cognition, affect

and arousal mediate an individual’s perception of a situation.

Thus, in the short term a violent video game may temporarily

increase aggression through the activation of one or more of these

domains. In the long term aggressive scripts can develop and

become more readily available [4]. Therefore the GAM can

explain how properties of a video game can affect players’

thoughts, feelings, physiological arousal and subsequent behav-

iour. Technological developments have afforded such games, and

subsequent gaming experience, to expand beyond the realms of

the console, and computer programmed opponents (offline

gaming), and now allow players to engage in video game play

with multiple players from all over the world via the internet

(online gaming). Schubert, Regenbrecht and Friedmann [20]

found that players who interact with other human players

experience a heightened sense of being part of the action.

Significant differences in physiological arousal and evaluations of

game experience, including presence and likability, have also been

found when video game opponents are controlled by other

humans [21]. In regards to the negative effects, increases in

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aggressive thoughts and hostile expectations have been found

when playing human opponents in a violent video game [22,23].

Further to this, Wei [24] found, from a survey of 312 Chinese

adolescents, that those who played violent video games online

against human opponents expressed a greater tolerance of

violence, a lower empathetic attitude and more aggressive

behaviour than those who played against computer opponents.

Based on previous studies, engagement with/against human

opponents may strengthen gaming experiences and therefore, in

accordance with the GAM, heighten their effects on players’

thoughts, feelings and behaviour.

As noted above, violent content within violent video games has

also been identified to increase levels of aggression. Within specific

violent video games, progression through gaming levels achieved

by engaging in violence poses an additional risk of increasing levels

of aggression. Carnagey and Anderson [25] found that rewarding

violence increased in-game violence and that rewards for killing

other racing drivers and pedestrians, in the race-car video game

Carmageddon 2, increased levels of hostile emotion, aggressive thinking and aggressive behaviour. Sherry [26] identified that

video games that portray human violence were associated with

increases in levels of aggression, potentially due to higher rates of

action, and subsequent heightened nonspecific arousal. More

specifically, increases in experience of perceived difficulty,

enjoyment and action have yielded significant game effects on

aggressive thoughts [27]. These findings lend support to the

processes involved in the GAM.

One of the most popular violent gaming formats to date is the

First Person Shooter (FPS), in which the gamer experiences the

action through the eyes of the main protagonist, centred on a

projectile weapon. Reports indicate that a specific franchise,

utilising the FPS format, Call of Duty, a military war game, has broken all previous sales records. Call of Duty: Modern Warfare 2, made $550 m (£350 m) in the first five days of sale. This was surpassed by Call of Duty: Black Ops and Call of Duty: Modern Warfare 3, which made $650 m (£412 m) and $775 m (£490 m) in sales respectively [28]. FPSs have been found to significantly

increase hostility and aggression from base line levels [29]. Based

on anecdotal evidence much of the success of this franchise has

been attributed to features of online game play.

Despite the popularity of the genre, to date, there is a lack of

research that has attempted to investigate the effect of playing

violent video games, specifically FPSs, online on levels of

aggression.

Overview of the present research In the present research, we examined whether playing a FPS

online would exacerbate the negative effects of violent video game

play on aggression. Further to this we examined the effect of

particular game experiences including perceived difficulty, enjoy-

ment and action, previously identified to be associated with

increases in aggressive thoughts [27], on levels of behavioural

aggression. To this end, participants played either a violent video

game online or offline, or a neutral video game online or offline.

Afterwards, aggressive behaviour was assessed. It was expected

that playing a violent video game would increase aggression. It was

also expected that participants who had played the violent video

game online would show the highest levels of aggression (relative to

the remaining three experimental conditions) due to the previously

identified experiences specific to online game play. Finally, we

examined whether these proposed effects would hold when

controlling for perceived difficulty, enjoyment and action.

Ethical approval was given by the University of Sussex’s School

of Life Sciences Research Governance Committee (Ethical

Approval Reference: RBJH0510). All relevant data are within

the paper and its Supporting Information files.

Method

Within this paper the authors report how we determined our

sample size, all data exclusions (if any), all manipulations, and all

measures in the study. One hundred and one students (64 men

and 37 women; ages range from 18 to 44: M = 21.38, SD = 4.00) from a UK University participated in the study in exchange for

course credits or payment. After being welcomed by the examiner

all participants were asked to complete a consent form.

Participants were randomly assigned to one of four experimental

conditions; 26 participants in a neutral video game offline, 26

participants in a neutral video game online, 23 participants in a

violent video game offline and 26 participants in a violent video

game online. Participants were advised that they would be

undertaking two unrelated marketing surveys that had been

combined for the economy of time. The first would ask for their

views about a popular video game and the second would involve a

marketing survey for a new recipe of hot chilli sauce.

The first task involved playing a video game for thirty minutes

[29] either offline or online. In the offline condition participants

were allowed to play against computer characters, subject to the

video game’s narrative. In the online condition participants played

against human opponents via the internet, utilising randomly

computer selected pre-existing levels, thus reducing the time spent

navigating menus. In the online conditions, when appropriate,

participants were requested to wait patiently whilst the server

selected and loaded following levels. There was no opportunity for

players to communicate with other human players via the internet

in the online condition. The audio was turned off in all conditions

to prevent participants being exposed to other players’ attitudes or

opinions in the online condition and to promote consistency. The

gaming approach and engagement of online opponents was not

recorded. All participants were initially introduced to a Playstation

3 computer console. The type of video game (violent and neutral)

was identified using their Pan European Game Information

(PEGI) ratings. Participants in the neutral video game condition

were introduced to LittleBigPlanet 2, certificate 7, a game that would normally be rated suitable for all age groups but contains

scenes that may be considered frightening for young children [30].

LittleBigPlanet 2 allows players to create, explore, solve puzzles, and interact with fantasy environments which they can enjoy or

share online with other gamers. All participants in the neutral

condition played the initial training level and were then allocated

to either the offline condition, subject to the game’s narrative, or

online condition, able to engage freely with the game’s online

content, for the remainder of the experiment. Participants in the

violent video game condition were introduced to Call of Duty: Modern Warfare, certificate 18. Call of Duty: Modern Warfare is a FPS that sets gamers as soldiers tasked to kill the enemy in various

environments. Games with a certificate 18 depict extreme violence

including multiple, motiveless killing and violence towards

defenceless people that may make the viewer experience a sense

of revulsion [30]. All participants were asked to play the initial

level, that introduces players to the gaming controls, and then

were set up to play offline levels, following the narrative of the

game, or online levels, during which the player played against

other human operated opponents in free-for-all mode (Death-

match). Having played for the allotted time participants were then

asked to complete a number of questions about the game they had

just played. This survey investigated their attitudes towards the

games, including how violent they perceived the content and the

Online FPS Video Games on Levels of Aggression

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graphics to be. Among some filler items, participants indicated

how difficult they perceived the game to be (using two items,

a = .72), to what extent they enjoyed the game (using two items, a = .79), and how fast the action of the game was (using one item). All items were assessed on a Likert scale from 1 to 7.

Following this, some affective measures were employed. There

were no significant effects on these measures so this is not

considered further. Finally, participants completed a marketing

survey investigating a new hot chilli sauce recipe. Participants were

informed that they were not required to taste the hot chilli sauce

but to prepare an amount of chilli sauce for a taste tester. During

the instructions they were made aware that the taste tester

‘couldn’t stand hot chilli sauce’ but was taking part due to good

payment. They were presented with a hot chilli sauce, depicting

three out of three chillies for hotness, a spoon and a plastic

receptacle. The amount of chilli sauce was weighed in grams after

the participant had left the experiment. The chilli sauce paradigm

has been successfully used in previous studies to measure

behavioural aggression in the laboratory environment [31]. All

participants completed all parts of the experiment with none

admitting to knowing the true purpose of the study, therefore all

data was included within the study. At the conclusion of the

experiment all participants were offered a comprehensive debrief

form which included information as to the true purpose of the

experiment.

Results

The manipulation check identified that participants in the

violent video game condition reported that the violent video game

Call of Duty: Modern Warfare 2 (M = 4.08, SD = 1.29) depicted a more violent content and more violent graphics compared to the

neutral video game LittleBigPlanet 2 (M = 1.41, SD = 0.89), F(1, 97) = 146.97, p,.001, gp

2 = .60.

A 2 (type of video game: violent vs. neutral) x 2 (setting: online

vs. offline) analysis of variance (ANOVA) on the amount of chili

sauce (aggression measure) revealed a significant main effect of

type of video game, F(1, 97) = 8.63, p = .004, gp 2

= .08. Partici-

pants who had played the violent video game were more

aggressive (M = 16.12, SD = 15.30) than participants who had played the neutral video game (M = 9.06, SD = 7.65). The main effect of setting, F(1, 97) = 0.35, p = .558, gp

2 = .00, and the

interaction were not significant, F(1, 97) = 1.44, p = .234, gp

2 = .02.

To test our specific prediction that aggressive behaviour, grams

of chilli sauce dispensed by participants, would be particularly

pronounced after playing a violent video game online, planned

contrasts were performed, which are particularly adequate to

answer such specific research questions [32,33]. In fact, partici-

pants who had played the violent video game online were more

aggressive (M = 16.81, SD = 16.57; contrast weight: 3) compared to participants who had played the violent video game offline

(M = 15.35, SD = 14.04; contrast weight: 21), participants who had played the neutral video game online (M = 6.92, SD = 7.62; contrast weight: 21), and participants who had played the neutral

video game offline (M = 11.19, SD = 7.20; contrast weight: 21), t(97) = 2.07, p = .041 (Figure 1). Note, however, that the orthog- onal contrast comparing the violent video game offline condition

(contrast weight: 2) with the neutral video game online (contrast

weight: 21) and the neutral video game offline (contrast weight: 2

1) condition was also significant, t(97) = 2.09, p = .039. Finally, the orthogonal contrast comparing the neutral video game online

(contrast weight: 1) with the neutral video game offline (contrast

weight: 21) condition was not significant, t(97) = 1.28, p = .202. This pattern of data suggests that both playing violent video games

online and offline compared to playing neutral video games

increases aggression.

The violent video game (M = 4.11, SD = 1.48) was perceived as being more difficult than the neutral game (M = 2.71, SD = 1.18), F(1, 97) = 27.11, p,.001, gp

2 = .22. Participants also enjoyed the

violent video game more (M = 4.81, SD = 1.46) than the neutral game (M = 3.76, SD = 1.38), F(1, 97) = 13.34, p,.001, gp

2 = .12.

The violent video game (M = 5.00, SD = 1.47) was also perceived as having faster action than the neutral video game (M = 2.94, SD = 1.56), F(1, 97) = 46.06, p,.001, gp

2 = .32. Note, however,

that in a multiple regression the effect of type of video game

(violent vs. neutral) was still significant when controlling for these

video game ratings, b = .27, t(96) = 2.15, p = .034. Moreover, none

Figure 1. Mean grams of chilli sauce by experimental condition. doi:10.1371/journal.pone.0111790.g001

Online FPS Video Games on Levels of Aggression

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of the video game ratings received a significant regression weight,

all bs,.15, all ts,1.29, all ps..202.

Discussion

The present study examined the effect of playing a violent video

game online and the impact of game experience including

perceptions of difficulty, enjoyment and action on levels of

behavioural aggression. Supporting previous research, this study

found that playing a violent video game in comparison to a neutral

video game significantly increased levels of aggression [3–6].

However, this main effect was not particularly pronounced when

the game was played online. That is, both playing the violent video

game online and offline relative to playing a neutral video game

increased levels of aggression.

It is important to note that the violent and the neutral video

game differed in terms of perceived difficulty, enjoyment and

action, with the violent game perceived as being more difficult,

more enjoyable, and being faster. However, when controlling for

these video game properties, there was still a significant influence

of type of video game on aggression. To put it differently, the effect

that playing the violent relative to the neutral video game increases

aggression is not due to differences in perceived difficulty, enjoyment and action. It should be noted, however, that

controlling for potential confounders within video game research

should be viewed with caution [34].

It should be acknowledged that the violent and the neutral video

game chosen for this study may differ in properties other than

difficulty, pace of action, and enjoyment. For example, the first-

person shooter game, even when played offline (alone), contains a

great deal of competitive content (competing in shooting battles for

survival against other computer-generated characters), whereas

the neutral video game contains little to no competitive content.

Importantly, previous research has demonstrated an effect of

competitive video game content (i.e., competing against other

computer-generated characters in a game) on aggressive behavior

in the short-term [35] and long-term [36]. Unfortunately, we did

not control for competitive content so it may well be that our

finding that violent video games increase aggression can be (in

part) accounted for by differences in how competitive the game is

perceived to be. This is certainly an important endeavor for future

investigations.

With the growing popularity and prevalence of online video

gaming, more specifically the engagement with violent video

games online, and evidence to suggest that playing against human

opponents can heighten the gaming experience, we thought it an

important endeavor to investigate whether violent video games

played online would exacerbate any negative effects on aggression.

As expected, online violent video game play relative to the three

remaining experimental increased aggression. However, inasmuch

as offline violent video game play relative to the neutral video

game conditions also significantly increased aggression, we have to

conclude that the violent video game affected aggression but that

this effect was not further strengthened by playing the game

online. Because this is the first study to have examined the effects

of online violent video game play on aggression, we hasten to add

that more research is needed before the conclusion is warranted

that playing online vs. offline has no consequences on the player’s

social behavior. For instance, future research may address the

effects of online violent video game play on behavioural aggression

in the long term. Differences in perceived competition when

playing video games online and offline should also be explored.

Further to this, future research should investigate the properties of

violent video games experienced online that impact on players’

aggressive cognitions, affect, physiological arousal and behaviour.

Consideration could also be given to potential positive effects of

playing prosocial video games online. Previous research has shown

that playing a prosocial video game (where the main objective of

the game is to benefit video game characters) increases prosocial

behaviour [37–39] and empathy [40] and decreases the accessi-

bility of aggressive thoughts [41] and reduces aggressive behaviour

[42]. Likewise, playing cooperative team-player (relative to a

single-player) video games increases cooperative behaviour and

empathy and decreases aggressive cognitions and angry feelings

[43–49]. It may well be that prosocial and antisocial outcomes are

even more affected by prosocial and cooperative video games

when played online.

It is important to acknowledge a limitation in regards to the

video games selected in this study. The perspective of the FPS is

specific, and the authors are unaware of a neutral video game that

utilises the first person perspective. It may be possible, in the

future, to identify a non-violent first person perspective video game

and thus better match the characteristics of the violent and neutral

video games. As a result, LittleBigPlanet 2 was selected for its low PEGI rating and ease of operating the controls (unrelated to game

difficulty). It should also be conceded that the two online

conditions differed in that participants competed against human

opponents in the first-person shooter game, whereas the neutral

video game allowed players to play competitively and coopera-

tively. This possible confound might have led to increased

aggression in the online/violent (relative to the offline/violent)

video game condition and decreased aggression in the online/

neutral (relative to the offline/neutral) video game condition (that

is, an interaction between type of video game and setting).

However, we did not find this interaction, but simply a main effect

of type of video game. In fact, it is compelling that despite these

differences in online/offline shooter games that they did not differ

in their effect on aggression.

Further to this some concerns have been raised as to the

suitability of the chilli sauce paradigm as an accurate measurement

of behavioural aggression within the laboratory environment [50].

In addition the current sample size was relatively small and

therefore limits the generalisability of the results. Future research

should increase the experimental population and may examine the

effects of violent video games online on other measures of

aggression.

In conclusion this study has identified that increases in

aggression are not more pronounced when playing a violent video

game online in comparison to playing a neutral video game online.

This is an important finding in relation to the growing online

community and popularity of violent video games, specifically

FPSs, and the potential for subsequent increases in aggression. We

think there should be concern about the harmful effects of playing

violent video games but it appears that playing the game online

does not further exacerbate these effects.

Supporting Information

File S1 SPSS data file.

(SAV)

Author Contributions

Conceived and designed the experiments: JH TG. Performed the

experiments: JH. Analyzed the data: TG. Contributed reagents/materi-

als/analysis tools: JH TG. Wrote the paper: JH TG.

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PLOS ONE | www.plosone.org 5 November 2014 | Volume 9 | Issue 11 | e111790