This paper proposes a model for studying elements of game design rooted in neuropsychology. By examining these elements in a context of other forms of art and the biological functions of the intended audience, we hope to point the way for further aesthetic advancement in this most lively new form.
We argue that enjoyment in game play is a product of the evolution of the human mind, an increasingly common point of view in the field. In The Ambiguity of Play, Sutton-Smith (1996) indicates:
"Play [is] a reinforcement of potential synaptic variability through the performance of variable antics, and... as a fuller imitation of the evolutionary process itself, in which the organism models its own biological character"
It is important to make the distinction between pure, or "free" play and games with codified rules. The former is observed in virtually all mammals and some species of birds, while the latter appears to be exclusively confined to homo sapiens [1].
The most successful game designs present the user with the opportunity to seek closure and to displace the sense of self. These two features evolved in the brain to support survival and social stability.
- Predictive closure
Predictive closure is the capacity of the mind to suggest consistent completion of a mental model, filling information gaps with a reasonable inference based on witsh learned information. The effects of this form of closure are familiar in many fields including vision, psychology and art, and simple closure is present in animals with far less developed neural systems than human beings.
If, for example, a predator is only partly visible, closure enables potential prey to assume that the rest of the predator exists. "In an incomplete world, we must depend on closure for our very survival" (McCloud 1994)
The human mind extends the quest for closure from these early vision processes to higher levels of conscious thinking, in order to maximize the pleasure induced by successful closure (Ramachandran&Hirstein 1999). Artists began to employ predictive closure en masse with the Op Art movement, incorporating gestalt closure and other optical illusions from the study of vision into their art. The player extends predictive closure towards a game, thus forming the first part of a feedback loop that is inherent to enjoyment. This urge for completion underlies our interest in hearing the end of a piece of music, or seeing the end of a movie - the loops of prediction have been opened in the mind of the audience, and we will not rest until we find out what happens.
- Dramatic Closure
Dramatic closure is a feature common to many forms of art, including literature, music, and computer games. It appears to stem from the property of consciousness that requires formation of a story structure, or internal dialouge. This personal storytelling allows the mind to maintain a stable identity and a sense of self. (Dennett 1992)
This form of closure has been adequately described in the cases of drama (Hiltunen 1999) and music (Hofstadter 1979), explaining how satisfaction arises from the resolution of tension. However, there has been little academic exploration of the aesthetic uses of tension and release in game design, although designers themselves are well aware of this structure (Falstein 1999).
The simplest example of dramatic closure may be found in the popular game Tetris. While the drama of Tetris is simple, it is clear-cut - the player succeeds, or fails, a single row at a time, defeating an enemy that emerges from chaos. The individual quadrominoes begin to take on an archetypical character: the linear piece is the saviour; the s-shaped piece, the trickster in two forms. In some sense, each player's journey through the state space of the game is a tiny epic, overcoming obstacles to defeat a greater evil.
However, Tetris never permits the final, highest level of closure - the game only ends when the player has failed at a series of smaller closures. This is the root of the addictiveness of the game - it causes a state of tension that can never be fulfilled, but can be temporarily sated by further small closures. The falling blocks which fill the minds of devoted players are much akin to the melody which rings in your ears after the song is gone, parodied in "Who Framed Roger Rabbit." Roger is drama incarnate, and is done in by the need for closure.
- Relationship between Dramatic and Predictive Closure
These two forms of closure create a feedback loop between them, where the expectation of resolution drives the player to perform the actions needed to reach closure. Typically, these actions are repetitive, and in a well-structured game, there will be multiple hierarchical levels of sub-closures.
In Miyamoto's landmark The Legend of Zelda: Ocarina of Time, Link is driven to a final resolution, saving the land of faeries, through a series of subquests in which he rescues representatives of air, earth, fire, and water. Song structure is one element used to create this dramatic tension, as the player must learn and play melodies and different times in the game to drive the action.
Link begins the game as a young boy, around ten years of age, and he is introduced to a pony, Epona. Her keeper teaches Link "Epona's Song", and the horse bonds with Link. Learning the song is itself a small puzzle, with a minor closure of its own. Later in the game, Link has aged, and is now a young man. When he plays the same haunting melody, the fully-grown Epona, now running wild in a ruined land, remembers the song, and will thus serve as his loyal steed.
- Somatic
Somatic displacement refers to the ability of a person to project the mental model of his or her own identity into another physical form, which represents the player in an alternate environment. There are some examples of somatic displacement in other human activities, such as driving a car - successful automotive navigation requires the driver to project their body image to the physical limits of a car. When one is involved in a car accident, one typically says "he hit me!" rather than "his car hit my car!"
Many games play upon this form of displacement of the self. For example, computer games set in the third person require a user to project their self-image into the character on the screen. First person games require the user to project their entire body image into a virtual environment, a phenomenon referred to commonly as immersion.
Krueger (2000) noted that users have little trouble projecting their body image into their representation naturally, even if this representation is highly distorted, such as by perspective. Indeed, it is difficult not to displace your representation into a physical form you control.
"The brain is wired to understand... faces and bodies... It is surprisingly easy to control your flat hand in a 3D space, even when mapped onto a curved plane."
This physical displacement of self is familiar to many game players, and accounts for some of the most appealing and popular games. The chart-topping Tomb Raider series, for example, projects the player into the pneumatic body of Lara Croft, a beautiful and athletic young woman. She is capable of running, jumping, and doing perfect backflips in pursuit of her many quests, this providing players with a the vicarious thrill of physical mastery.
In several of the Super Mario games, Mario acquires the gift of flight. Interestingly, his form of flight is that form familiar to from dreams - a temporary swooping release from the bonds of gravity. The fact that this skill is not innate, and can only be acquired as an aspect of a magic hat, the thrill of achievement at the point of first becoming airborne is tangible, typically leaving the player breathless.
Physical displacement does not seem to be required in games in general - abstract games such as Tetris and chess, for example, both have have very weak displacement, if any. However, in representational games, this displacement is required to insert the ego of the user into the closure loop, so that a reward will be perceived as coming "to" the user, rather than to make it an abstraction. This phenomenon is very similar to identification with a character in a movie, for example, except that there is rarely much physical engagement in cinema.
- Temporal
Temporal Displacement is the prediction of hypothetical situations, including the predicted point of view of another person. In The Feeling of What Happens, Damasio (1999) explains the neural basis for the self and its displacement, which Damasio calls the "extended consciousness"
"Extended consciousness goes beyond the here and now of core consciousness, both backward and forward. The here and now is still there, but it is flanked by the past, as much past as you may need to illuminate the now effectively, and just as importantly, it is flanked by the anticipated future."
Survival endowed us with the ability to predict the future based on our mental models, which allowed us to survive and flourish beyond all other creatures. Any complex game play requires this. In The Man Who Mistook His Wife For A Hat, Sacks relates an anecdote about the Lost Mariner, a man who suffered from neurological damage that reduced his active memory to a span of roughly one minute. Locked in a perpetual now, he was able to play simple games and puzzles, such as tic-tac-toe, but unable to extend his working memory or conception of future event well enough to engage in more complex games such as chess.
It is possible that the Lost Mariner, an inexperienced chess player, merely lacked the attention span to maintain a mental model of a game long enough to select a suitable move. It seems more likely, however, that he lacked the ability to displace himself into the future and understand the effects of his moves.
- Relationship between Temporal and Somatic Displacement
While temporal displacement is a requirement for survival - even less intellectually advanced species than ourselves can make some predictions about the future - somatic displacement appears to be a modern phenomenon, linked to the use of technological advancements. Indeed, this capacity for projection of the ego is rather surprising, as related by Krueger (2000):
"I realized that the image as a representation of the person is instinctive. It was as if the DNA didn't care if it was in this or that body. The image was an extension to the self, and what happens to the image seems to happen to the person... We had two cameras set up, one pointed at each of our computer screens, and the two images composited together. His hand was reaching up from the bottom; my hand could reach up from the top. At one moment, the image of my hand touched the image of his hand, and he suddenly jerked his hand away. He didn't want to hold hands with me! Well, my feelings were hurt but I thought this was a revelation."
What evolutionary advantage could this skill confer? A best guess might be that it it is a natural extension of the ability to displace ourselves temporally. The ability to imagine yourself in a different time is the same as the ability to imagine yourself in a different body.
Computer games are, in the authors' opinon, the most important form of art being made at the turn of the century. While they have many structural features in common with other media, there are a number of unique aspects that have not been deeply studied in this context. At least two of these, displacement and closure, can be discussed in terms of their neuropsychological basis, thus shedding light on factors that distinguish an aesthetically pleasing experience from one that is less successful.
[1] Even though there have been some cases of apparent game play in young mammals (Fagen 1981), such as "king of the hill," the rules may not be strictly codified from their point of view; we might be anthropomorphizing, imposing our own standards on spontaneously arising play behaviour.