Brain Topography

, Volume 26, Issue 4, pp 547–557 | Cite as

Age-Related Task Sensitivity of Frontal EEG Entropy During Encoding Predicts Retrieval

  • Denis O’Hora
  • Stefan Schinkel
  • Michael J. Hogan
  • Liam Kilmartin
  • Michael Keane
  • Robert Lai
  • Neil Upton
Original Paper


Age-related declines in memory may be due in part to changes in the complexity of neural activity in the aging brain. Electrophysiological entropy provides an accessible measure of the complexity of ongoing neural activity. In the current study, we calculated the permutation entropy of the electroencephalogram (EEG) during encoding of relevant (to be learned) and irrelevant (to be ignored) stimuli by younger adults, older adults, and older cognitively declined adults. EEG entropy was differentially sensitive to task requirements across groups, with younger and older controls exhibiting greater control of encoding-related activity than older declined participants. Task sensitivity of frontal EEG during encoding predicted later retrieval, in line with previous evidence that cognitive decline is associated with reduced ability to self-initiate encoding-related processes.


EEG Memory Aging Entropy 



DOH was supported by a Grant from ERASMUS and by sabbatical leave from the School of Psychology at NUI Galway. SS was supported by the German Research Foundation (DFG) in the Research Group FOR 868Computational Modeling of Behavioral, Cognitive, and Neural Dynamics. Supplementary material is available in the online version of this article. The software used for this study will be provided at:

Supplementary material (1.1 mb)
Supplementary material (ZIP 1,167 kb)


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Denis O’Hora
    • 1
  • Stefan Schinkel
    • 2
  • Michael J. Hogan
    • 1
  • Liam Kilmartin
    • 3
  • Michael Keane
    • 4
  • Robert Lai
    • 5
  • Neil Upton
    • 5
  1. 1.School of Psychology, NUI GalwayGalwayIreland
  2. 2.Departments of Physics and PsychologyHumboldt Universität zu BerlinBerlinGermany
  3. 3.College of Engineering and Informatics, NUI GalwayGalwayIreland
  4. 4.School of Nursing and Human SciencesDublin City UniversityDublin 9Ireland
  5. 5.Exploratory Medical Sciences, Neurology CEDD/CPDM/NFSP NorthHarlowUK

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