People who have good language skills in their early 20s might stay 'with it' longer in old age even if their brains are showing the physical signs of Alzheimer's disease. Researchers at Johns Hopkins University in Baltimore carried out autopsies on the brains of 38 nuns. 10 of them had asymptomatic Alzheimer's with the plaques and tangles in the brain characteristic of the condition but no symptoms, five had mild cognitive impairment (MCI), 10 had Alzheimer's and 13 had no cognitive problems or changes to their brain. The researchers also analysed essays that 14 of the women had written in their teens or early twenties when they entered the convent. They looked at 'idea density' - the average number of ideas expressed for every ten words - and grammatical complexity. They found that the early writings of the women who died with no cognitive deficits were significantly denser in ideas than the essays written by the women with MCI or Alzheimer's although there was no difference between the two groups as far as grammatical complexity was concerned. The brains of the nuns with asymptomatic Alzheimer's had larger cells in many areas of the brain as well as larger cell structures such as nuclei and nucleoli - a finding consistent with earlier studies into this issue suggesting that their brains had adapted to cope with the damage caused by Alzheimer's.
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