Cooper and Mackie (1986): Video Games and Aggression

Why investigate video games and aggression?

Cooper and Mackie’s 1986 study investigated whether violent video games affected children’s behaviour, particularly whether boys and girls responded differently. It belongs to criminal psychology because aggression is one possible form of antisocial behaviour. However, studying children’s play is not the same as studying criminal offending.

Earlier research suggested that watching television violence could increase children’s aggressive behaviour. Much of this research had used male participants. Video games offered a new comparison: a child could actively participate in the action as a player, or watch the same action as an observer.

This connects with social learning theory, which explains how behaviour can be learnt through observing and imitating others. If watching aggression influences later behaviour, direct participation might not be necessary. Comparing players with observers therefore helped investigate whether active involvement made a difference.

The researchers also considered arousal, meaning physical and psychological activation. Previous research suggested that frequent viewers of violence showed less physiological arousal in response to new violence than children with less exposure. Cooper and Mackie reasoned that girls’ lower experience of violent media and gaming at that time might make their responses more pronounced. This was a proposed explanation, not a claim that all girls or boys respond alike.

The aim and predictions

The aim was to investigate the effects of computer-generated games depicting substantial violence on children, especially differences between boys and girls.

The researchers predicted that boys and girls would perceive video games differently, and that aggressive games would have a greater effect on children’s behaviour than non-aggressive games.

Comparing games and participation

The study was a laboratory experiment: the researchers controlled the gaming situation and measured behaviour afterwards. It used an independent-measures design, so different children experienced different conditions.

There were two manipulated independent variables:

• Game condition: high aggression, low aggression or control.
• Participation: playing the game or observing a partner play.

Each child took part in only one game condition and was either a player or an observer. Boys’ and girls’ responses were also compared, but sex was a participant characteristic rather than something the researchers manipulated.

The high-aggression game was Missile Command, which involved substantial violence and shooting. The low-aggression game was Pac-Man, in which the character chased and was chased by ghosts through a maze. It involved less violence and almost no shooting. Pac-Man was therefore the less aggressive comparison, not a game entirely without aggression.

The control activity was a paper-and-pen maze: children used magic markers to solve mazes featuring Star Wars and Tron characters, which were popular with their age group at the time. Televisions and video-game equipment were used for the video games.

Later behaviour was measured through observation of toy play and a separate measure of interpersonal aggression, meaning aggression directed towards another person. Questionnaires gathered information about gaming experience and perceptions of the games.

Who took part and how were conditions allocated?

The sample consisted of 84 children: 44 boys and 40 girls, from fourth- and fifth-grade classes in suburban Trenton, New Jersey, USA. Parental consent was obtained. Children were paired randomly, with the restriction that partners had to be of the same sex and school grade.

A week before the experimental session, children completed a questionnaire about their previous gaming experience. During the experiment, each pair was randomly allocated to Missile Command, Pac-Man or the control maze. One member was then randomly chosen to play for eight minutes, while the other observed.

The experimenter recorded the player’s cumulative game score. Observers could advise or encourage their partners, but were not allowed to participate in the game.

Measuring behaviour in the toy room

Players next went to a room containing four pre-selected, coded toys:

• Aggressive: a three-foot-high plastic Shogun Warrior with a spring-releasing fist and dart-firers.
• Active: a Nerf Basketball set with a shooting net.
• Skill: a table-top Pop-up Pinball game.
• Quiet: Lincoln Logs and roofing pieces for building.

Children were told they could play with any toys while waiting for an observer to ‘work some things out’. The observer sat in a corner and covertly recorded which toys were used, in what order and for how long. The children were therefore not told that their toy play was being measured.

This made aggression measurable through toy choice and time spent playing. However, choosing the Shogun Warrior was not the same as attacking someone: the measure concerned aggressive play, rather than directly observed harm to another person.

Measuring imagined punishment and reward

While players were in the toy room, their observer partners completed the interpersonal measure in another room. Each child chose the worst of three behaviours: talking back, hitting someone or stealing something. They imagined another child performing that behaviour and selected a punishment: not being allowed out to play, restricted television or being sent to their room.

The child pressed a red button to indicate how much punishment they would give: the longer the press, the more punishment. This was repeated for a second and third occurrence of the bad behaviour. Children could retain their chosen punishment or select another, and button-press duration was recorded on each trial.

A similar procedure covered good behaviour: helping someone, stopping a fight or cleaning up their room. Possible rewards were getting a surprise, not having to do a chore or staying up later. Finally, children ranked the punishments and rewards from worst to best. No actual punishment or reward was administered to another child.

After eight minutes of toy play, players moved to the interpersonal measure and their observer partners moved to the toy room. They exchanged testing locations, not gaming roles.

Before returning to class, all children completed a manipulation-check questionnaire and questions about their perceptions of the games. Five-point rating scales assessed action and violence. Children also reported how much they liked the game. Players indicated how much they wanted to continue playing; observers indicated how much they had wanted to play.

Gaming experience and perceptions

The experience questionnaire showed that 34 of the 44 boys, compared with 17 of the 40 girls, had video games at home. Overall, 73 of the 84 children had previously played a video game, and average daily playing time was 42.57 minutes. These findings help explain why previous experience mattered when interpreting differences between boys and girls.

Children rated the maze as the least violent and active game, followed by Pac-Man and then Missile Command. This supported the intended ordering of the conditions: the high-aggression game was actually perceived as more violent.

Players in every condition perceived their game as more active than their observer partners did. Girls playing the maze or Pac-Man thought they had performed better than girls playing Missile Command. Boys were more strongly confident about their performance and similarly confident across all three games.

Boys enjoyed playing more than watching. Girls generally enjoyed observing more than playing, except in the maze condition. Female maze players liked their game more than female players of either video game, whereas boys were equally happy playing all three games.

Female players wanted to continue less than female observers wanted to take part. For boys, the reverse pattern occurred, especially with Missile Command: players’ desire to continue was stronger than observers’ desire to play.

What changed in toy play?

The video games, especially Missile Command, had much more effect on girls’ than boys’ free play. Compared with the other two games, Missile Command increased girls’ aggressive play and general activity, while reducing their quiet and skill play. Pac-Man tended to increase girls’ quiet play and decrease their general activity.

Boys’ behaviour was largely unaffected by game condition, but there were exceptions: skill play decreased in both video-game conditions, and overall activity decreased in the Pac-Man condition. The conclusion is therefore that boys showed much less behavioural change, not that every measure remained unchanged.

Cooper and Mackie concluded that playing and observing had the same effects on subsequent behaviour. Active participation was therefore not necessary for the main toy-play effect found here.

Did aggression towards other people increase?

Game condition did not affect the interpersonal aggression measure. Boys pressed the button more than girls in both the punishment and reward tasks. Because the difference appeared for rewards as well as punishments, longer presses should not automatically be interpreted as greater hostility.

Button-press duration increased over successive trials, with the greatest increase among players rather than observers. This trial pattern is distinct from the finding that the type of game did not affect interpersonal aggression.

The researchers concluded that playing or observing the games did not increase interpersonal aggression in boys or girls. A child choosing an aggressive toy more often shows a change in play behaviour, but this is not evidence that the child becomes more violent towards people. Likewise, this experiment cannot establish that video games cause crime.

What does the study tell us about social learning?

The similar effects of playing and observing on toy play are consistent with the idea that observing aggressive media can influence subsequent behaviour. The findings therefore offer some support for a social-learning explanation of aggression.

However, the support is limited rather than universal: effects differed between boys and girls and between the measures of aggression. Arousal and previous experience provide possible alternative or additional explanations. The study did not directly demonstrate that every change resulted from imitation.

The research contributes to the nature–nurture debate by examining an environmental influence on behaviour. Differences between boys and girls do not, by themselves, prove an innate difference: the groups also differed in gaming experience. Responses to the same media exposure can depend on individual experience and the behaviour being measured.

Evaluating the evidence

A strength was the controlled comparison between game conditions and between players and observers. Using standardised tasks and timings helped make comparisons more systematic. The perception ratings also checked that the games differed in violence as intended. An independent-measures design avoided children’s responses being affected by experiencing several games in succession.

However, different children brought different previous experiences into each condition. Random allocation helped reduce systematic differences, but could not guarantee identical groups. Excitement, confidence or familiarity with gaming could influence later toy choices.

The setting and tasks limit ecological validity. A short assigned gaming session followed by toy play differs from choosing and playing games naturally at home. Covert recording reduced the chance that children deliberately changed their toy play because they knew it was being measured, but did not make the whole setting natural.

There is a construct-validity problem with treating aggressive toy play or a button response as aggression. These measures may capture interest, excitement or decisions about punishment rather than an intention to harm someone. Using more than one measure was useful, but the absence of a game effect on interpersonal aggression makes a broad claim about increased aggression difficult to justify.

The sample came from children in one American location. Findings may not generalise to other ages, cultures or levels of gaming experience. Games and access to gaming have also changed since 1986, so the findings should not automatically be applied to all modern games.

Finally, the study measured immediate effects rather than lasting changes. Parental consent was an ethical safeguard, although exposing children to violent material raises concerns about possible distress, and covert observation raises issues about informed consent to the recording of behaviour.

Overall, the study supports a narrow conclusion about short-term play behaviour, particularly among girls in this sample, rather than a claim that violent games inevitably produce aggression or criminality.