# Implementation and Evaluation of a Serious Game for Working Memory Enhancement
## 2 Theoretical Background
### Rationale for Supporting Working Memory Training with Serious Games  
WM is a kind of memory that allows the transfer of information into long-term memory, which can temporarily store new information, creating suitable conditions for recall--when needed--in order to be used or stored permanently [35]. It is the type of memory which facilitates attention preservation and attempts to create visuo-spatial designs in order to not create cognitive loads by overloading the already limited memory, but to help the brain perform cognitive tasks more easily. Since WM is a key factor in activating attention to preserve information--even temporarily--in order to create connections with other types of memory, or to have the appropriate encoding which will facilitate cognitive function, it is realized that it is important to include WM in the development of an SG. Almost every factor taken into consideration for the successful design of an SG is strongly connected, either directly or indirectly, to WM. Thus, apart from the user's enjoyment, WM constitutes another factor that should be considered when designing SGs. Recently, several SGs for cognitive training have been developed which directly target the training of cognitive functions by utilizing mental exercises in games, called \"brain training\". Games like \"Sudoku\" and crossword puzzles constitute examples of simple yet effective games which support brain training. Sudoku, for example, relies on short-term memory, since in order to successfully complete a Sudoku puzzle, you have to be able to make predictions and follow trails of consequence. This type of planning helps improve short-term memory and concentration. A well-known platform is \"Lumosity\" ([[http://www.lumosity.com/](http://www.lumosity.com/)]([http://www.lumosity.com/](http://www.lumosity.com/))), which aims to enhance attention, WM and executive functions. Lumosity's brain training and mental fitness games, tests, and activities are backed by science. Other similar options are:  
* BrainHQ ([[https://www.brainhq.com/](https://www.brainhq.com/)]([https://www.brainhq.com/](https://www.brainhq.com/))),
* CogniFit ([[https://www.cognifiit.com/](https://www.cognifiit.com/)]([https://www.cognifiit.com/](https://www.cognifiit.com/))),
* NeuroSky ([[http://neurosky.com/](http://neurosky.com/)]([http://neurosky.com/](http://neurosky.com/))),
* MindMaze ([[https://www.mindmaze.com/](https://www.mindmaze.com/)]([https://www.mindmaze.com/](https://www.mindmaze.com/))),
* Braintrain (www.braintrain.com),
* Brain Metrix (www.brainmetrix.com),
* CogniFit Brain Fitness (www.cogniift.com) and more. The approach chosen in these programs relies on performing short tasks repeatedly and with increasing levels of difficulty. Most brain training games have been developed for healthy elderly people and people with mild cognitive impairments. Evidence for the effectiveness of these brain training games is inconclusive, as the effects of the training generally are not generalized beyond the training itself [35; 36]. Cognitive training applications, and specifically WM training systems, are designed to improve the user's WM. However, conventional systems are frequently considered tedious or repetitive, which deeply affects the user's motivation to learn and consequently the potential for learning transfer [37]. According to [PERSON] et al. [38], WM training with game elements significantly improves motivation and training performance. A game is considered to be \"serious\" if it offers strong motivation for an objective, provides simple and clear directions, increases the attention and focus of the player, offers scalable and adaptive difficulty, and all these are supported in a fun environment. The connection of the SGs with cognitive training can be found in the fact that cognitive training has also got specific goals which motivate the subject. Moreover, it requires the subject's increased attention and concentration.