One extra year of school was tied to fewer dementia diagnoses decades later
A 1972 change in England, Wales and Scotland raised the school-leaving age from 15 to 16, creating a natural comparison between people born just before and just after 1 September 1957. Researchers followed more than 100,000 UK Biobank participants to age 65 and found the extra year was associated with a 0.88% lower incidence of Alzheimer's disease and related dementias, with the clearest difference among people carrying higher genetic risk. The authors urge caution because participants were only followed to 65, so the gap could grow or shrink as the group ages.
Source: National Institutes of Health
Frequent daytime naps — especially unintended ones — went with higher later dementia risk
In an observational study, 995 US adults aged 65 and older who were free of dementia in 2013 were followed for up to ten years. Those who napped most days or every day had a 48% higher risk of developing dementia than those who rarely or never napped, while unintentional naps carried a 39% higher risk and naps of 30 minutes or less a 40% higher risk. The researchers stress this does not prove naps cause dementia: changing nap patterns could instead be an early sign of brain changes, and nap habits were self-reported.
Source: Johns Hopkins Bloomberg School of Public Health
Deaf children given sign language from birth matched hearing peers on early number skills
Researchers assessed 178 deaf and hard-of-hearing children aged 3 to 7 on counting and on understanding that the last number counted names the size of the whole set. Children who had American Sign Language or spoken English at home from birth performed at a level comparable to hearing children learning spoken language at home, and better than children whose language access began later — even after accounting for family socioeconomic background. The authors conclude that timing of language access, not deafness itself, shaped early number development.
Source: Phys.org