Brain aging reversed by as much as 50 years.
It causes the brain to flood with dopamine, a neurotransmitter strongly linked to positive emotions.
Discovery of the receptor could lead to better drugs for depression and anxiety.
People can learn to control their brain waves when they are given feedback about the electrical activity in their brains.
Without abstract thought, we would be unable to do maths or science, create laws or think about human emotions.
The system could eventually translate thoughts into words automatically.
Both our genetics and the circumstances of our lives influence the exact shape that our brains form.
Male brains (top) show greater connectivity front-to-back, while female brains (bottom) are more connected across the hemispheres.
A fascinating new study on the brains of 949 young people finds striking gender differences in the brain’s connectivity between males and females (Ingalhalikar et al., 2013).
These may help explain some of the classic psychological differences between men and women.
The study uses a type of brain imaging–diffusion tensor imaging–which can reveal the microscopic structures of the living brain.
From the 428 males in the study, the researchers found that the connections in men’s minds ran more between the front and the back, within the same half of the brain.
This may help to explain men’s advantage with motor and spatial skills over women since front-to-back connections help link perception with action.
In the brains of the 521 females in the study, the researchers noted more overall connections between the two hemispheres of the brain.
This may help explain women’s improved memory and social skills, the authors argue, since communication between the halves of the brain helps link intuition with analysis.
The participants in the study were aged between 8 and 22-years old, as the researchers were looking for clues about how the brain develops.
They found that there were few differences between males and females before the age of 13, but that the different patterns of connectivity kicked in at puberty.
One of the study’s authors, Ruben Gur commented:
“It’s quite striking how complementary the brains of women and men really are. Detailed connectome maps of the brain will not only help us better understand the differences between how men and women think, but it will also give us more insight into the roots of neurological disorders, which are often sex related.”
Image credit: Ragini Verma, Ph.D., Proceedings of National Academy of Sciences
“Hidden caves” that open up in the brain may help explain sleep’s amazing restorative powers.
A new study published in the prestigious journal, Science, has found that the brain may wash away toxins built up over the day during sleep.
The research discovered “hidden caves” inside the brain, which open up during sleep, allowing cerebrospinal fluid (CSF) to flush out potential neurotoxins, like β-amyloid, which has been associated with Alzheimer’s disease.
To reach their discovery, researchers injected mice’s brains with a dye and monitored the flow while they were awake, asleep and anaesthetised (Xie et al., 2013).
One of the study’s authors, Dr Maiken Nedergaard, explained the results:
“We were surprised by how little flow there was into the brain when the mice were awake. It suggested that the space between brain cells changed greatly between conscious and unconscious states.”
For a long time the real physiological purpose of sleep has remained a mystery.
We know that lack of sleep causes all kinds of psychological problems like poor learning, decision-making and so on.
We also know that animals that are chronically deprived of sleep will eventually die: flies or rodents in days to weeks, humans within months or years.
Everyone who has ever enjoyed a blissfully good night’s sleep knows just how restorative it can be, but the actual physiological process wasn’t clear.
This study, though, suggests that the flushing out of toxins by the CSF may be central to sleep’s wondrous powers.
The interstitial spaces in the mouse’s brain took up only 14% of the brain’s volume while it was awake. Yet, while it slept, this increased by almost two-thirds to take up fully 23% of the brain’s total volume.
The difference might seem slight, but the actual physiological effects are profound.
During the day, the CSF mostly covers the surface of the brain. During sleep, though, the CSF is able to move deep inside.
The effect is that potential neurotoxins, like β-amyloid, are cleared twice as fast during sleep as during waking.
The results of this study–if they hold in humans–may help to explain why many neurological diseases, like strokes and dementia, are associated with problems sleeping.
It could be that lack of sleep, and restriction of the brain’s cleaning system, may cause toxic metabolites to building up, leading to long-term damage.
→ Related: 10 Sleep Deprivation Effects.
Image credit: HaoJan Chang
New study demonstrates that the brain treats social pain in a similar way to physical pain.
Being rejected by other people is no fun.
Contrary to the old ‘sticks and stones’ saying, it seems words can and do hurt, and the brain responds accordingly.
A new study from the University of Michigan Medical School has found that the body produces natural painkillers in response to social rejection, just as if it had suffered a physical injury (Hsu et al., 2013).
The lead author, Assistant Professor David T. Hsu, explained:
“This is the first study to peer into the human brain to show that the opioid system is activated during social rejection. In general, opioids [are] released during social distress and isolation in animals, but where this occurs in the human brain has not been shown until now.”
In the study, social rejection was simulated in the lab. Eighteen participants were asked to look at fictional online dating profiles and choose some they were interested in.
Then, while lying in a PET scanner, they were told they’d been rejected by their potential online dates.
The scans showed that in response to the rejection, the brain sent out painkillers in the form of opioids into the spaces between neurons. This dampens down the pain signals.
In fact participants knew in advance that the online dating profiles were not real, and neither was the rejection. Nevertheless, the simulated situation was still enough to set off the release of painkillers.
Participants who were highly resilient were the most likely to produce high levels of the natural painkiller.
At the other end of the scale, those with low painkiller production may be particularly vulnerable to rejection. One of the authors, Professor Jon-Kar Zubieta explained:
“It is possible that those with depression or social anxiety are less capable of releasing opioids during times of social distress, and therefore do not recover as quickly or fully from a negative social experience.”
This is further evidence that social pain is not as different from physical pain as many thought. More and more research is pointing to an overlap in the brain’s response to both.
Image credit: josemanuelerre
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