Scientists have debunked the myth that extreme athletes are adrenaline junkies with a death wish.
Australian researchers behind a just-published study say there has been a "gross misunderstanding" of what motivates people to take part in extreme sports like base jumping, big wave surfing and solo rope-free climbing.
"Our research has shown people who engage in extreme sports are anything but irresponsible risk-takers with a death wish," said Professor Eric Brymer, a psychology researcher at Queensland University of Technology and UK's Leeds Beckett University.
"They are highly trained individuals with a deep knowledge of themselves, the activity and the environment who do it to have an experience that is life-enhancing and life-changing."
Because extreme sports participants found it hard to put their experiences into words, a research project led by Brymer and colleague Professor Robert Schweitzer took a new approach to understanding data collected for it.
"Rather than a theory-based approach which may make judgements that don't reflect the lived experience of extreme sports participants, we took a phenomenological approach to ensure we went in with an open mind," Schweitzer said.
"This allowed us to focus on the lived-experience of extreme sport with the goal of explaining themes that are consistent with participants' experience.
"By doing this we were able to, for the first time, conceptualise such experiences as potentially representing endeavours at the extreme end of human agency, that is making choices to engage in activity which may in certain circumstances lead to death."
'Bionic skin' a step closer
Scientists have developed a revolutionary process for 3D printing that could give robots the ability to feel their environment - and something that has taken the world closer to printing electronics on human skin.
"This stretchable electronic fabric we developed has many practical uses," said Associate Professor Michael McAlpine, a mechanical engineering researcher University of Minnesota.
"Putting this type of 'bionic skin' on surgical robots would give surgeons the ability to actually feel during minimally invasive surgeries, which would make surgery easier instead of just using cameras like they do now.
"These sensors could also make it easier for other robots to walk and interact with their environment."
His team made the unique sensing fabric with a one-of-a kind 3D printer they built in the lab, which has four nozzles to print the various specialised "inks", including a base layer of silicon.
McAlpine, who gained international acclaim in 2013 for integrating electronics and novel 3D-printed nanomaterials to create a "bionic ear", says this new discovery could also be used to print electronics on human skin.
This ultimate wearable technology could eventually be used for health monitoring or by soldiers in the field to detect dangerous chemicals or explosives.
"While we haven't printed on human skin yet, we were able to print on the curved surface of a model hand using our technique," McAlpine said.
"We also interfaced a printed device with the skin and were surprised that the device was so sensitive that it could detect your pulse in real time."
Can trusting your doctor be a placebo?
US scientists have simulated doctor check-ups and flu jabs to reveal that trusting your GP can be its own form of placebo.
Their goal was to find ways to help people feel less pain when seeing the doctor, and reduce phobias about check-ups.
"Pain also has a psychological component as well, and it's the interaction between the psychological and physiological aspects of pain that we're really interested in," said Dr Elizabeth Losin, a psychology researcher at the University of Miami College of Arts and Sciences.
In the study, participants had applied heat to their inner forearm, which was designed to simulate a painful medical procedure like a shot.
The findings revealed that the more patients reported trusting their doctor and feeling similar to them, the less pain they reported feeling from the heat on their arm.
The study also suggested that participants who experienced higher levels of anxiety on a day-to-day basis experienced greater reductions in pain from feeling close to their doctor.
"Overall, we are interpreting our findings as suggesting that the doctor is essentially acting as a social placebo, playing the same role that a sugar pill would play if we were doing a study on placebo pain relief," Losin said.
"When someone believes that something is going to help relieve their pain, their brain naturally releases pain-relieving chemicals.
"Our hypothesis, based on what we are seeing, is that trusting and feeling similar to the doctor who is performing the painful procedure is creating that same kind of placebo pain relief."
Facebook's lure linked to part of your brain being smaller
Ever find yourself checking your Facebook constantly throughout the day?
Researchers from Germany's Ulm University have found social media use to be associated with lots of activity in an area of your brain called the nucleus accumbens - a region which plays a big part in reward and addiction.
Instead of relying solely on self-reported social media use, the researchers used a unique combination of real-life usage data from participants' Facebook apps and neuroscientific data from structural brain scans.
The comparison showed that the volume of grey brain matter - which contains most of the brain's neuronal cell bodies - of the nucleus accumbens was smaller for frequent Facebook users.
The researchers, whose work has just been published in the journal Behavioral Brain Research, explain that the study gives more support to the rewarding aspect of posting that selfie.
'Waves of lava' spotted in space
Scientists have revealed waves of lava rolling across a massive molten lake on one of Jupiter's moons.
In 2015, Europa passed in front of another moon of Jupiter, Io, gradually blocking out light and allowing scientists to accurately isolate the heat emanating from volcanoes on Io's surface.
Infrared data showed that the surface temperature of Io's massive molten lake steadily increased from one end to the other, suggesting that the lava had overturned in two waves that each swept from west to east at about a kilometre each day.
Overturning lava is a popular explanation for the periodic brightening and dimming of the hot spot, called Loki Patera after the Norse god.
The most active volcanic site on Io, which itself is the most volcanically active body in the solar system, Loki Patera is about 200km across.
Earthbound astronomers first noticed Io's changing brightness in the 1970s, but only when Voyager spacecraft flew by in 1979 did it become clear that this was because of volcanic eruptions on the surface.
Despite highly detailed images from NASA's Galileo mission in the late 1990s and early 2000s, astronomers continue to debate whether the brightenings at Loki Patera - which occur every 400 to 600 days - are due to overturning lava in a massive lave lake, or periodic eruptions that spread lava flows over a large area.
"If Loki Patera is a sea of lava, it encompasses an area more than a million times that of a typical lava lake on Earth," University of California scientist Katherine de Kleer said.
"In this scenario, portions of cool crust sink, exposing the incandescent magma underneath and causing a brightening in the infrared."