The project saw more than half a million Britons aged 37-73 studied over five years, taking memory and IQ tests.
Cilmi baarista ayaa lagu falanqeeyay hab nololeedyada in ka badan 500 oo kun oo British ah oo da'doodu u dhaxeyso 37 ilaa 73 sano jirro muddo shan sano, waxaa la baaray waqtigaasi fahamkooda iyo xusuustooda.