Study: Is modernity leading to a growing Cognitive Divide?

Sub­ject dur­ing EEG study. Cour­tesy of Sapi­ens Labs

—

Has Mod­ern Expe­ri­ence Changed The Human Brain? (NPR):

“The brain has evolved over evo­lu­tion­ary time scales of mil­lions of years. So, what is the like­li­hood that the rel­a­tive­ly recent advent of read­ing and writ­ing, or motor­ized trans­port, or the Inter­net, could have changed our brains?…

A study out of India, still under­go­ing peer review, in which sci­en­tists look at EEG mea­sures in diverse pop­u­la­tions across India may shed some light on the question.

It has long been known that awake sub­jects with eyes closed show a pat­tern of neur­al oscil­la­tion in the so-called alpha band (8–15 Hz) and this has been tak­en to be a fun­da­men­tal cere­bral rhythm that may be tied to atten­tion, learn­ing abil­i­ty, and work­ing memory…For the study, Indi­an schol­ars Dhanya Para­mesh­waran and Tara Thi­a­gara­jan per­formed EEG mea­sure­ments on 402 sub­jects from 38 dif­fer­ent set­tle­ments across India — rang­ing from remote ham­lets to large cities…

The find­ings of the study are dra­mat­ic. The exis­tence of alpha-band activ­i­ty was basi­cal­ly unde­tectable in peo­ple who lack wealth, edu­ca­tion and knowl­edge of mod­ern technology…Can the world afford to con­fine alpha rhythms to the 15–20 per­cent who, by the cri­te­ria of this study, enjoy the income, edu­ca­tion and tech­nol­o­gy con­ducive to cog­ni­tive and neu­ro­log­i­cal development?

There is also a fas­ci­nat­ing method­olog­i­cal upshot. The vast major­i­ty of cog­ni­tive sci­ence has been done on WEIRD sub­jects — that is, sub­jects sam­pled from West­ern, Edu­cat­ed, Indus­tri­al­ized, Rich, Demo­c­ra­t­ic soci­eties. But recent schol­ar­ship sug­gests that this fact may con­ceal real vari­a­tion across human communities.”

The Study

Mod­ern­iza­tion, Wealth And The Emer­gence Of Strong Alpha Oscil­la­tions In The Human EEG (not peer-reviewed yet). 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.

To Learn More