Weird News

More bedtime could mean earlier death

Regularly spending more than nine hours in bed could be linked to a higher risk of early death.

Scientists found that people who slept for more than nine hours a night had a 17 per cent higher chance of dying from any cause compared with those getting seven to eight hours. Researchers tracked the sleeping habits of more than 3,000 people over three decades and found mortality was lowest among those sleeping seven to eight hours each night. There were 10.57 deaths per 1,000 people during the study among this group. That figure rose slightly to 10.97 among people sleeping fewer than six hours and to 11.27 among those sleeping more than nine hours.

The Taiwanese researchers said the reasons for the association were unclear, but pointed to several possible explanations. People who sleep for longer periods are more likely to have high blood pressure, which is a major risk factor for heart disease and stroke. Longer sleep has also been linked to increased inflammation and may affect the body’s internal clock, hormone regulation and immune system.

Writing in the Journal of Sleep Research, the researchers said: “These findings may have implications for identifying individuals at increased health risk – sleep duration assessment may be incorporated into routine health check-ups to help identify individuals at potentially increased health risk.”

Newborns focus on different things after birth

Baby girls are more interested in people than boys from their very first hours of life, while newborn boys appear more fascinated by objects, research suggests.

Scientists at the University of Cambridge studied 130 babies just hours after birth, before they had experienced the toys, expectations and social influences that can shape childhood. Each newborn was shown two videos side by side. One featured a human face, while the other showed a Newton’s cradle, a desk toy made from suspended metal balls that swing into one another. Both sexes generally preferred the face, but girls spent more time watching it than boys, who devoted more attention to the moving metal balls.

The findings suggest some average differences in behaviour may have biological influences, rather than being entirely shaped by upbringing. Yumnah Khan, who led the study at Cambridge’s Autism Research Centre, said: “Recent research has also shown that on-average sex differences are present in brain structure at birth and emerge prenatally.

“This new study tells us that there are not only on-average sex differences in the brain, but also in attention and behaviour.”

Professor Sir Simon Baron-Cohen, who oversaw the research, said the findings addressed whether biology helped shape differences between male and female minds.

He said the fact that differences were visible within hours of birth, before extensive experience outside the womb, suggested “prenatal factors play a role”.

Those factors could include “sex hormones and/or genes”, he said.

The expert added: “In other words, it’s nature and nurture, not nature or nurture.”

New discoveries made about brains’ origins

Scientists say the human brain is made from two ancient nervous systems that evolved separately.

Researchers at Stanford University found that the front and back of the brain follow fundamentally different developmental pathways, suggesting they were once separate systems that were eventually brought together through evolution. The hindbrain controls vital automatic functions including breathing, sleep, heartbeat and hunger, while the forebrain and midbrain are responsible for higher-level abilities such as language, consciousness, reasoning, vision and voluntary movement.

Dr Kyle Loh, an author of the study, said: “We’ve shown for the first time that the front of the brain arises from a totally different progenitor cell than the back of the brain.”

The team studied developing mouse embryos and found that cells destined to become the forebrain and midbrain express a gene called Otx2, while hindbrain cells express Gbx2. They also discovered major differences in the way DNA is packaged in the two regions.

The finding could have major implications for studying diseases affecting the brain and nervous system.