Virtual Reality in Brain-Computer Interface Research
F. Lee 1, R. Scherer 2, H. Bischof 1, G. Pfurtscheller 2
1) Institute for Computer Graphics and Vision2) Institute for Human-Computer Interfaces
Outline Overview of Brain Computer
Interface (BCI) Problems in BCI research Studierstube combined with BCI Experiments Further work
Brain Computer Interface A Brain-Computer Interface is a
communication system that do not depend on peripheral nerves and muscles
Applications: Patient with severe movement disorders:
Control external devices (neuroprosthesis, wheelchair) by mental focus
Entertainment (games) Military Use (fighter pilots)
Graz BCI system Graz-BCI system based on classification
of motor imagery related brain activity changes in ongoing EEG Electrodes placed on the scalp Movement imagination (left hand, right
hand, foot or tongue)
Homunculus
Primary Somato Sensory Cortex
Primary Motor Cortex
Motor execution vs. Movement imagination
Imagination
Execution
Subject g3, 16-20 Hz Subject f7, 20-24 Hz
ERD ERS500mstime
Simplified model of the BCI system
Problems in BCI Research Time-consuming training
Which kind of movement imagination is better?
Impact of visual stimulus on the motor cortex activity and resulting EEG Can lead to deterioration of motor
imagery related EEG pattern Correct visual feedback should help user
to get more control on the own brain activity
Goal Design an accurate BCI system
which needs only few training sessions Investigation of different classification
methods Presentation of „better“ visual
feedback Studierstube (stereoscopic 3-D scene, tracking)
BCI combined with Studierstube
Experiments Rotate the cube by mental focus
Observation of Movement
•Feature extraction: adaptive autoregressive parameter•Feature mapping: PCA•Feedback: rotation, size, color of cube
Further work
Virtual flat Navigastion: e.g
moving into bathroom
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