Psychophysiological game research faces the problem that for understanding the player experience, it needs to analyze game metrics and events with high temporal resolution and within the game context. This way greater understanding of gameplay and the player experience can be achieved with the use of physiological instrumentation. This is a presentation of a paper that presents a solution to recording in-game events and metrics, by sending out event byte codes through a parallel port to the physiological signal acquisition hardware. Thus, psychophysiological data can immediately be correlated with in-game data. By employing this system for psychophysiological game experiments, researchers will be able to analyze gameplay in greater detail in future studies.

1. Log Who’s Playing:
Psychophysiological Game Analysis
Made Easy Through Event Logging
Lennart Nacke, Craig Lindley, Sophie Stellmach
Blekinge Institute of Technology, Sweden
Department of Interaction and System Design
Game and Media Arts Laboratory

2. Outline
 Motivation for our work
 Conceptual design
 Automated game event logging
– Details
– A word about gaze logging
 Conclusion and future work

3. Motivation
 Understand user behavior by decoding events
 Evaluation data accompanied by video
– Qualitative data
– Behavioral data
 Improvement by adding even-related physiological data
– Specific phasic response in event context
 What makes gameplay fun?

4. Conceptual design
 Meaningful events
– In-game events
 User-created
 Pre-defined and triggered
– Real-world events
 Sensors (physiological, positional, etc.)
 Video
 Record at run-time speed of 3d game engine
 Interface with physiological recording hardware
– Parallel port (200 ms accuracy)
 Easy integration into editing tools

5. IMPLEMENTED IN
SOURCE SDK

6. Types of logging

7. Event-code examples
105:
Pressing
red button
55:
Player fires
a gun
21:
Damage to smiling
opposing NPC

8. Automated game logging
 Transmission component
– Interfacing class
– Communication with physiological recording hardware
 Event component
– Common (level-independent)
 Enemy is killed, etc.
– Unique (level-dependent)
 Player enters area, etc.
 Dynamically assign unique events in editing tool
CBaseEntity
Event_Log Logging_Entity
Private
Input Output
Data
Functions Functions
Members

9. Dynamically assigning events
Screenshot showing the logging entities and manually defined output
codes inside the Hammer editing tool for the Half-Life 2 Source SDK.

10. Correlation of Physiological Data to Events
Physiological data is recorded together with real-time game events,
allowing for automatic data clustering and analysis

11. Main benefit: time reduction for researcher
 Data correlation is fully automated
Experiment Data Analysis
Preparation
Correlation

12. A word about gaze logging
 Automatically logs and identifies
– Game objects
– Graphical assets
 Tobii 1750 (SDK)
– Video-based
– Corneal-reflection tracking
 Logs
– Object ID
– Event ID
– Time stamp
– L+R gaze points (x,y)

13. Dissecting player experience
 Surveys
– Pre-game
– (In-game)
– Post-game
 Physiological responses
– Emotion
– Cognition
– Arousal
 Visual attention
– Gaze tracking
 Game Metrics

14. Conclusion and future work
 Event-logging enables detailed understanding
– of game experience
 Automatic data correlation saves analysis time
 Studies using the system are ongoing
 First results will be coming in shortly

15. Thank you kindly for listening!
me Craig Sophie
cld@bth.se slm@bth.se
Lennart Nacke
Find me at…
Blekinge Institute of Technology
Game and Media Arts Laboratory
Karlshamn, Sweden
Lennart.Nacke@bth.se
http://gamescience.bth.se
http://www.acagamic.com
Download papers from: http://gamescience.bth.se/research/publications