Brain Topography

, Volume 5, Issue 3, pp 241–251 | Cite as

Alpha frequency, cognitive load and memory performance

  • W. Klimesch
  • H. Schimke
  • G. Pfurtscheller


EEG-signals were recorded from subjects as they performed a modified version of Schneider's and Shiffrin's memory search paradigm. The hypothesis was tested whether individual (centre of gravity) alpha frequency, termed IAF, is related to memory performance and/or attentional demands. The results show that memory performance exerts the strongest effect on IAF. As compared to a resting period, the difference in IAF between age-matched good and bad memory performers reached a maximum when subjects were actually retrieving information from their memory. During retrieval, the IAF of good performers is 1.25 Hz higher than for bad performers. Attentional and task demands also tend to reduce IAF, but- as compared to memory performance - to a much lesser degree. The results of amplitude analyses demonstrate further that during retrieval, alpha desynchronization is more pronounced for bad performers than for good performers. Taken together, the results indicate that a decrease in IAF is always related to a drop in performance.

Key words

Alpha frequency Event related desynchronization Memory performance Encoding Retrieval Attention 


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Copyright information

© Human Sciences Press, Inc. 1993

Authors and Affiliations

  • W. Klimesch
    • 1
  • H. Schimke
    • 1
  • G. Pfurtscheller
    • 2
  1. 1.Department of Physiological Psychology, Institute of PsychologyUniversity of SalzburgSalzburgAustria
  2. 2.Ludwig Boltzmann Institute of Medical InformaticsUniversity of TechnologyGrazAustria

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