Neural Computing and Applications

, Volume 31, Issue 3, pp 945–953 | Cite as

Fractal dimension methods to determine optimum EEG electrode placement for concentration estimation

  • Hossein Siamaknejad
  • Wei Shiung LiewEmail author
  • Chu Kiong Loo
Original Article


In this study, fractal dimension approaches were used for analyzing EEG to determine the optimum electrode placement to distinguish between concentration and relaxation states. The EEG of participants was recorded from multiple electrode placements while under relaxed state and while in a state of heightened mental activity. Higuchi and Katz algorithms were applied to extract the fractal dimension FD indices of windowed segments of the EEG. These were then plotted in a graph, and a simple threshold was applied to best divide the indices of relaxation and concentration. The Higuchi algorithm was found to be better than Katz at distinguishing between relaxation and concentration, and P3 was found to be the best position to measure concentration, with P8 being a close contender.


Fractal dimensions Electroencephalogram Medical signals Attention estimation 



This study was funded by University of Malaya High Impact Research (HIR) Grant UM.C/625/1/HIR/MOHE/FCSIT/10.

Compliance with ethical standards

Conflict of interest statement

We declare that we have no potential conflicts of interest.


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Copyright information

© The Natural Computing Applications Forum 2017

Authors and Affiliations

  1. 1.Faculty of Computer Science and Information TechnologyUniversity MalayaKuala LumpurMalaysia

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