Modernization, Wealth And The Emergence Of Strong Alpha Oscillations In The Human EEG

Parameshwaran, D.; Thiagarajan, T. C.

doi:10.1101/125898

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bioRxiv · 10.1101/125898

Modernization, Wealth And The Emergence Of Strong Alpha Oscillations In The Human EEG

Parameshwaran, D.·Thiagarajan, T. C.

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Abstract

Oscillations in the alpha range (8-15 Hz) have been found to appear prominently in the EEG signal when people are awake with their eyes closed, and since their discovery have been considered a fundamental cerebral rhythm. While the mechanism of this oscillation continues to be debated, it has been shown to bear positive relation to memory capacity, attention and a host of other cognitive outcomes. Here we show that this feature is largely undetected in the EEG of adults without post-primary education and access to modern technologies. Furthermore, we show that the spatial extent and energy of the oscillation have wide variation, with energy ranging over a thousand fold across the breath of humanity with no centralizing mean. This represents a divergence in a fundamental functional characteristic of an organ demonstrating both that modernization has had a profound influence on brain dynamics and that a meaningful average human brain does not exist in a dynamical sense.

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Parameshwaran, D., Thiagarajan, T. C.. 2017-04-11. Modernization, Wealth And The Emergence Of Strong Alpha Oscillations In The Human EEG. https://doi.org/10.1101/125898

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