Medical & Biological Engineering & Computing

, Volume 49, Issue 9, pp 985–995 | Cite as

An EEG-based real-time cortical functional connectivity imaging system

  • Han-Jeong Hwang
  • Kyung-Hwan Kim
  • Young-Jin Jung
  • Do-Won Kim
  • Yong-Ho Lee
  • Chang-Hwan ImEmail author
Original Article


In the present study, we introduce an EEG-based, real-time, cortical functional connectivity imaging system capable of monitoring and tracing dynamic changes in cortical functional connectivity between different regions of interest (ROIs) on the brain cortical surface. The proposed system is based on an EEG-based dynamic neuroimaging system, which is capable of monitoring spatiotemporal changes of cortical rhythmic activity at a specific frequency band by conducting real-time cortical source imaging. To verify the implemented system, we performed three test experiments in which we monitored temporal changes in cortical functional connectivity patterns in various frequency bands during structural face processing, finger movements, and working memory task. We also traced the changes in the number of connections between all possible pairs of ROIs whose correlations exceeded a predetermined threshold. The quantitative analysis results were consistent with those of previous off-line studies, thereby demonstrating the possibility of imaging cortical functional connectivity in real-time. We expect our system to be applicable to various potential applications, including real-time diagnosis of psychiatric diseases and EEG neurofeedback.


Electroencephalography (EEG) Functional connectivity Real-time neuroimaging Diagnosis of psychiatric diseases Inverse problems 



This work was supported in part by the KRISS-WCL project (Development of Measurement Technology for Cognitive Process) and in part by the Original Technology Research Program for Brain Science through the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education, Science and Technology (No. 2010-0018840)

Supplementary material

Supplementary material 1 (MPG 1168 kb)


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Copyright information

© International Federation for Medical and Biological Engineering 2011

Authors and Affiliations

  • Han-Jeong Hwang
    • 1
    • 2
  • Kyung-Hwan Kim
    • 2
  • Young-Jin Jung
    • 1
    • 2
  • Do-Won Kim
    • 1
    • 2
  • Yong-Ho Lee
    • 3
  • Chang-Hwan Im
    • 1
    Email author
  1. 1.Department of Biomedical EngineeringHanyang UniversitySeoulSouth Korea
  2. 2.Department of Biomedical EngineeringYonsei UniversityWonjuKorea
  3. 3.Korea Research Institute of Standard and ScienceDaejeonKorea

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