Brain Analysis While Playing 2D and 3D Video Games of ... - UTPedia

To be able to gain knowledge of the human brain and study the perception of man towards stimulated events, emotions and sense, scientists have used few main methods. Meanwhile, the prq project will focus on the use of EEG to analyze the human brain. The EEG shows electrical impulses from the brain and can be recorded in the form of waves.

The purpose of this project is to use EEG equipment to analyze the activity of the human brain when playing console game Nintendo 3DS in 2-dimensions (2D) mode and 3-dimensions (3D) mode. The aim of this project is also to study and compare human brain perception of 2D and 3D games. Ultimately, the project will be able to explain and deduce how the human brain reacts to 2D and 3D games from Nintendo 3DS console games and what difference it makes in human visual brain system.

First of all, the author would like to express his utmost gratitude to God Almighty for his blessings and giving me health and life to complete this project. The author would like to express his gratitude to the Electrical And Electronic Engineering Department of Universiti Teknologi PETRONAS for giving the author the opportunity to do this project and Dr. Aamir Saeed Malik, his supervisor for his endless guidance, patience and idea while carrying out this brain analysis project. A person's state can be seen from the EEG, such as focused, awake, dizzy, drowsy, or unfocused, because the patterns of EEG signals are different from one state to another.

An important use of EEG is to display the time it takes for the brain to process different types of stimuli, whether graphic, audio or moving images [3).

Figure below shows the example of EEG electrodes placement on human head scalp and the recording of human brain activity using EEG

Visual Evoked Potential

Auto stereoscopic 3D of Nintendo 3DS brings new experience to users by letting them watch 3D content of the game without using glasses. The purpose of this project is mainly to study and compare the human brain's perception of 2D and 3D games on Nintendo 3DS by means of designated experiments, obtaining the signals generated by the brain during the game with Nintendo 3 DS in the experiments by to use EEG equipment, and further process and analyze the signals to explain brain activity while playing 2D and 3D games. The scope of this project is to research the anatomy, psychology and nervous system of the human brain, design event-related potential experiments, conduct experiments using EEG equipment and further analyze the collected data using signal processing tools.

The research is important to better understand how the human brain perceives 2D and 3D games and what difference they make to our brains when we play them. The result of this project will benefit scientists and psychiatrists to gain more knowledge about the differences between 2D and 3D games in the human brain.

Human Brain

In addition, the limbic system also regulates body temperature, blood pressure and blood sugar levels and performs various maintenance activities. The cerebrum occupies the other parts of the brain and comprises two-thirds of the total mass. The occipital lobe is the ultimate destination for visual information from the eyes, located at the back of the head.

Parietal Lobe Frorlal Lobe

Cerebellum Temporal Lobe

Previous Study of Brain Activity during Video Game Play

In the previous study, researchers examined dynamic brain activity during uninterrupted video game play using high-resolution EEG. The study shows that increased power is observed in the midline theta wave in the frontal lobe as a result of playing video games. Parietal alpha wave power was observed to increase as a result of video games, suggesting increased mental workload.

From this study, researchers can conclude from EEG analysis that a long period of gaming will increase the mental load of players.

CHAPTER3 MEffiODOLOGY

Experiment Method

Subjects are screened to ensure they are healthy and fit to perform the experiment. Participants can change the game mode from 2D to 30 by adjusting the Nintendo 3DS lever next to the top screen. The reasons for choosing this game are because it is easy to play and creates a nice 3D effect by creating depth between the fighting characters and the surrounding background of the game.

EEG signals were digitized with a sampling frequency of 255 kHz and a notch filter of 50 kHz. The recording of the experiment begins with 5 minutes of eyes closed followed by 5 minutes of eyes open to obtain a baseline of the participant's brain. For each recording segment, the participant was asked to sit upright, minimize eye blinking and muscle movements, and keep the eyes closed and open as much as possible according to the recording segments.

The participant will then play Nintendo 3DS's Super Street Fighter IV continuously in 20 mode for 20 minutes. After the participant finishes playing the 20, he or she will be given time to rest for a while before the 5-minute open-eye session is conducted. A questionnaire will be given to the participant at the end of the game to be completed (see APPENDIX).

The next figure shows the experimental setup as well as sample real-tme EEG signals obtained from a participant while playing Nintendo 3DS. Sample size of 20 participants is used for data acquisition, consisting of their EEG signals. The hardware and software used for recording EEG signals are BrainMaster 24e cap, amplifier and Toshiba Qosmio PC with BrainMaster recording software installed.

Before the start of each experiment/recording session, the participant must fill in his or her specific details, such as name, age, gender, and will be asked to sign a consent form and declare that he or she is voluntarily participating in the experiment. Afterwards, the experimenter will set up the participant with the BrainMaster 24e cap which consists of 19-channel electrodes and paired ear mount. After explaining the course of the experiment to the participant, the researcher starts the experiment and records the EEG signals using BrainMaster Software for the entire duration of the experiment, as mentioned earlier in the experiment method section.

Figure 3.5. Experimental setup and obtained EEG signal

Pre-Processing

A black line below the signals means that the signal has been removed and will not be considered for further processing. After performing artifact rejection, the next step is to select the remaining good portion of the EEG signal for analysis. It detects a similar pattern from the 10 second template selected earlier to determine the good parts of the EEG signal.

Red line below the signals indicates that the portion of signals is selected for processing. Processing of the cleaned signal is started by generating a report from NeuroGuide software that contains desired information of the EEG signal, such as Z-Score absolute power, coherence and phase delay values. Before that, information that wanted to be generated could be selected by Report->Report Selection.

These values are stored in Tab Delimited Text (*TOT) and can be opened with Notepad in Windows operating system. In order to see the values correctly, the TDT is further exported to Microsoft Excel sheets. To compare the EEG signal of 20 and 30, the data of each segment of 20 and 30 games of each participant is imported into MA TLAB for further processing.

In MA TLAB, codes are written to get Z-Score values of absolute power, coherence and phase delay from 20 and 3D and mathematical as well as logical operations are done to find the difference between 20 and 30 values. The difference of absolute power, coherence and phase delay maps and bar graphs for each frequency bands Delta, Theta, Alpha 1, Alpha 2, Beta 1, Beta 2, Beta 3 and High-Beta for each electrode are plotted and the matrix values are stored for results analysis .

Figure 3.9: NeuroGuide artefact rejection

CHAPTER4

RESULTS AND DISCUSSION 4.1 Z-Score

Absolute Power

Absolute power is defined as the sum of all powers within the specific frequency band, expressed in ).1 V2 [18]. The figures below show the result for absolute power difference between 20 and 3D at Occipital Lobe, the area where humans perceive visual information.