INCREASED GAMMA POWER: NEW DATA AGAINST OLD PREJUDICES
Reply to Klimesch on Brain-Rhythms

Abstract

Klimesch (1994) proposes that reduced spectral power in various frequency bands (the gamma-band included) is an indicator of increasing task difficulty. He argues against the possibility that the enhancement of gamma power could be an indicator of activation of a cortical cell assembly. Our response is the following: (1) Klimesch needs to spell out his model in terms of biological mechanisms. The result will probably be one within the cell assembly framework. (2) In recent experiments, focal enhancement of gamma-band power has been recorded in the EEG, whereby the local distribution is a critical factor which discriminates it clearly from the more unspecific type of distributions commonly found in the alpha or beta range.

Keywords

References

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