Rounding up science's latest discoveries
IT'S OKAY TO LET BABY CRY HIMSELF TO SLEEP
It's hard for parents to refrain from picking up a crying baby.
But a new study has found that allowing babies to gradually cry themselves to sleep does not cause them any emotional harm or stress in the long term.
Researchers from Flinders University in South Australia analysed the habits of 43 sets of parents with babies, aged between six and 16 months, that were experiencing problems sleeping.
After three months of tests, they found that babies who had been left to wail for increasing periods of time were falling asleep 13 minutes faster on average, compared with those who were picked up immediately.
The crying babies were not left alone for hours on end. Rather, the "wait time" before the babies were attended to built up from two minutes to 35 minutes over the course of a week.
PAINKILLERS WORSEN CHRONIC PAIN
It is a vicious circle when it comes to taking painkillers for your chronic pain, a new study has found.
Opium-based painkillers are not only addictive, but they can also worsen the very condition they were given to treat.
In a study on rats, researchers at the University of Colorado-Boulder found that opioid use increases chronic pain.
They said the study showed that just five days of morphine treatment in rats caused chronic pain that continued for several months by triggering the release of pain signals from immune cells in the spinal cord.
This has shown, for the first time, that even a brief exposure to opioids can have long-term negative effects on pain.
WHY OLDER PEOPLE TAKE FEWER RISKS
The older we get, the less willing we are to take risks.
A study has found the reason: Falling levels of dopamine as people get older makes them less attracted to big rewards, which in turn makes them less likely to take a big gamble.
Dopamine is a chemical in the brain that affects emotions, movements and sensations of pleasure and pain.
Scientists from University College London found that the drop in this neurotransmitting chemical makes older people more risk-averse when they looked at over 25,000 people, aged 18 to 69,play a smartphone app called The Great Brain Experiment.
They found that the older people in the group were less likely to choose risky gambles to win more points in the app.
The study found that a steady decline in risky choices with age matches the steady decline in dopamine levels, which fall by up to 10 per cent every 10 years of adulthood.
But when the volunteers were given a drug that boosted dopamine levels, they chose significantly more risky gambles to win more money.