What Happens in the Brain While Daydreaming?

The findings provide a clue that daydreams may play a role in brain plasticity
Image Credit: Scientific Frontline 

You are sitting quietly, and suddenly your brain tunes out the world and wanders to something else entirely — perhaps a recent experience, or an old memory. You just had a daydream.

Yet despite the ubiquity of this experience, what is happening in the brain while daydreaming is a question that has largely eluded neuroscientists.

Now, a study in mice, published Dec. 13 in Nature, has brought a team led by researchers at Harvard Medical School one step closer to figuring it out.

The researchers tracked the activity of neurons in the visual cortex of the brains of mice while the animals remained in a quiet waking state. They found that occasionally these neurons fired in a pattern similar to one that occurred when a mouse looked at an actual image, suggesting that the mouse was thinking — or daydreaming — about the image. Moreover, the patterns of activity during a mouse’s first few daydreams of the day predicted how the brain’s response to the image would change over time.

The research provides tantalizing, if preliminary, evidence that daydreams can shape the brain’s future response to what it sees. This causal relationship needs to be confirmed in further research, the team cautioned, but the results offer an intriguing clue that daydreams during quiet waking may play a role in brain plasticity — the brain’s ability to remodel itself in response to new experiences.

Enzymes Can’t Tell Artificial DNA From the Real Thing

Like adding new letters to an existing language’s alphabet to expand its vocabulary, adding new synthetic nucleotides to the genetic alphabet could expand the possibilities of synthetic biology. This image shows a rendering of RNA polymerase (center) and a synthetic nucleotide (lower right).
Image Credit: UC San Diego Health Sciences

The genetic alphabet contains just four letters, referring to the four nucleotides, the biochemical building blocks that comprise all DNA. Scientists have long wondered whether it’s possible to add more letters to this alphabet by creating brand-new nucleotides in the lab, but the utility of this innovation depends on whether or not cells can actually recognize and use artificial nucleotides to make proteins.

Now, researchers at Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of California San Diego have come one step closer to unlocking the potential of artificial DNA. The researchers found that RNA polymerase, one of the most important enzymes involved in protein synthesis, was able to recognize and transcribe an artificial base pair in exactly the same manner as it does with natural base pairs.

The findings, published in Nature Communications, could help scientists create new medicines by designing custom proteins.

Wildfires can unlock toxic metal particles from soils, Stanford study finds

Burned serpentine chaparral at McLaughlin Natural Reserve after the 2020 LNU Lightning Complex.
 Image Credit: Alandra Lopez

New research from Stanford University shows wildfires can transform a natural element in soils into a cancer-causing and readily airborne metal known as chromium 6.

Wildfires can transform a benign metal in soils and plants into toxic particles that easily become airborne, according to a new study from Stanford University.

Published in Nature Communications, the research documents high levels of a hazardous form of the metal chromium at wildfire sites with chromium-rich soils and certain kinds of vegetation compared to adjacent unburned sites. Known as hexavalent chromium or chromium 6, this is the same toxin made notorious by the 2000 film Erin Brockovich.

“Our study suggests far more attention should be paid to wildfire-modified chromium, and we presume additional metals as well, to more thoroughly characterize the overall threats wildfires pose to human health,” said lead study author Alandra Lopez, a postdoctoral scholar in Earth system science at the Stanford Doerr School of Sustainability.

This Japanese ‘dragon’ terrorized ancient seas

UC Associate Professor Takuya Konishi is an expert on ancient marine reptiles such as mosasaurs.
 Photo Credit: Joseph Fuqua II/UC

Researchers have described a Japanese mosasaur the size of a great white shark that terrorized Pacific seas 72 million years ago.

Extra-long rear flippers might have aided propulsion in concert with its long-finned tail. And unlike other mosasaurs, or large extinct marine reptiles, it had a dorsal fin like a shark’s that would have helped it turn quickly and with precision in the water.

University of Cincinnati Associate Professor Takuya Konishi and his international co-authors described the mosasaur and placed it in a taxonomic context in the Journal of Systematic Palaeontology.

The mosasaur was named for the place where it was found, Wakayama Prefecture. Researchers call it the Wakayama Soryu, which means blue dragon. Dragons are creatures of legend in Japanese folklore, Konishi said.

“In China, dragons make thunder and live in the sky. They became aquatic in Japanese mythology,” he said.

Trees are in trouble

 The trees in this lush, temperate forest in the Cascade Range of Washington are likely less resistant to drought than their counterparts in drier regions to the south.
Photo Credit Joan Dudney

This holiday season brings surprising news about your Christmas tree. Scientists just discovered that globally, trees growing in wetter regions are more sensitive to drought. That means if your tree hails from a more humid clime, it’s likely been spoiled for generations.

Scientists have long debated whether arid conditions make trees more or less resilient to drought. It seems intuitive that trees living at their biological limits will be most vulnerable to climate change, since even just a little extra stress could tip them past the brink. On the other hand, these populations have adapted to a harsher setting, so they might be more capable of withstanding a drought.

According to a new study in the journal Science by researchers at UC Santa Barbara and UC Davis, greater water availability could “spoil” trees by reducing their adaptations to drought. “And that’s really critical to understand when we’re thinking about the global vulnerability of forest carbon stocks and forest health,” said ecologist Joan Dudney, an assistant professor at UCSB’s Bren School of Environmental Science & Management and in the Environmental Studies Program. “You don’t want to be a ‘spoiled’ tree when facing a major drought.”

Clues to preventing Alzheimer’s come from patient who, despite genetics, evaded disease

A woman who never developed Alzheimer's despite a strong genetic predisposition may hold the key to stopping the disease in its tracks. Studying the woman's unique complement of genetic mutations, researchers at Washington University School of Medicine in St. Louis have found clues that could help cut the link between the early, asymptomatic stage and the late stage, when cognitive decline sets in.
Image Credit: AartlistDesign

Alzheimer’s disease has plagued one large Colombian family for generations, striking down half of its members in the prime of life. But one member of that family evaded what had seemed would be fate: Despite inheriting the genetic defect that caused her relatives to develop dementia in their 40s, she stayed cognitively healthy into her 70s.

Researchers at Washington University School of Medicine in St. Louis now think they know why. A previous study had reported that, unlike her relatives, the woman carried two copies of a rare variant of the APOE gene known as the Christchurch mutation. In this study, researchers used genetically modified mice to show that the Christchurch mutation severs the link between the early phase of Alzheimer’s disease, when a protein called amyloid beta builds up in the brain, and the late phase, when another protein called tau accumulates and cognitive decline sets in. So the woman stayed mentally sharp for decades, even as her brain filled with massive amounts of amyloid. The findings, published in the journal Cell, suggest a new approach to preventing Alzheimer’s dementia.

New treatment for deadly uterine cancer

left to right, Dr Asmerom Sengal, Professor Pamela Pollock.
Photo Credit: Courtesy of Queensland University of Technology

QUT scientists have discovered a promising new therapy for a deadly type of endometrial cancer that has a poor prognosis if the cancer spreads or returns after initial treatment, a plight that affects 15-20 per cent of endometrial cancer patients.

• Testing of new drug inhibited uterine tumor cell growth in lab and mice models

• The drug blocks the receptor of the growth factor in tumors that is associated with a low survival rate

• The inhibitor also reduced the tumors blood vessel formation

Dr Asmerom Sengal and Associate Professor Pamela Pollock from QUT’s School of Biomedical Sciences, published their research in Nature Precision Oncology with a recommendation that the strength of their findings indicated they should proceed to patient trials.

Dr Asmerom said endometrial cancer confined within the uterus could be cured with surgery however, if it had spread to the abdomen and other organs patients had limited treatment options.

“Previously, we found women with endometrial cancer who have an incorrect growth factor receptor called fibroblast growth factor receptor 2c (FGFR2c) on the tumor cell surface have a poor survival rate,” Dr Asmerom said.

Cutting-edge Biodiversity Models Will Help Assess Nature's Vital Contributions to People

Photo Credit: Pixabay

People depend on nature in a multitude of ways. Crop pollination, pest management, storm buffering, and carbon capturing are all part of nature's contributions to people (NCP). But these contributions are subject to change - species that make vital contributions may migrate or even go extinct due to climate change or habitat loss. Forecasting these changes is challenging, but also essential to ensure that humans are adequately prepared to respond.

Part of what makes this so challenging is that current NCP estimates typically rely on data incorporating the physical environment and omit information on species. Given that biodiversity is a cornerstone of NCP, many scientists recognize that biodiversity information can help us better assess the current and future state of NCP.

In a new opinion paper published in Trends in Ecology and Evolution, lead author Jamie M. Kass, associate professor and head of the Macroecology Lab at Tohoku University's Graduate School of Life Sciences, and an international team of colleagues argue that recent advances in biodiversity modeling and mapping have great potential for improving NCP estimates.

The 'one-pot' nanosheet method catalyzing a green energy revolution

Illustration Credit: Minoru Osada

A research group from the Institute for Future Materials and Systems at Nagoya University in Japan has developed a new “one-pot” method to make nanosheets using less rare metals. Their discovery should allow for the energy-making process to be more eco-friendly. The journal ACS Nano published the study.

Producing clean energy is important because it helps reduce global warming and contributes to building a carbon-neutral society. A potential source of clean energy uses hydrogen catalysts, such as palladium (Pd). Industries use Pd in electrolysis to separate water into hydrogen and oxygen. Afterward, the hydrogen in fuel cells is used to create electricity. The only byproduct is water. 

Pd is commonly used in a spherical ‘nanoparticle’ form for catalyst use. However, a flatter, thinner surface would use fewer precious metals and increase the available surface area for the reaction.

Minoru Osada at Nagoya University and his research group have developed a new way to make Pd nanosheets. They named it the "one-pot method" because it can be done in a single glass bottle. The resulting sheets were so thin (1~2 nm) that they can be compared to the size of a single molecule or DNA strand.

Women with PCOS can stress less about fertility

Photo Credit: Mart Production

Researchers from The University of Queensland have found that women with polycystic ovary syndrome (PCOS) respond well to fertility treatments and have the same birth rate as women without the condition.  

Dr Katrina Moss from UQ’s School of Public Health said the findings should offer some reassurance for women with PCOS who are concerned about their fertility.

“We studied 1109 women who were using fertility treatments and found no difference in births between the women with and without PCOS or between those on different treatment paths,” Dr Moss said.

“More women with PCOS used fertility treatment – 38 per cent compared to 13 per cent of women without PCOS, but the birth rate was equivalent, so women with PCOS were not disadvantaged.”

PCOS affects around 1 in 10 Australian women, causing irregular or absent ovulation making it difficult to fall pregnant.

Clinical practice guidelines recommend a stepped treatment for PCOS-related infertility – ovulation induction (OI) followed by intrauterine insemination (IUI) and finally, IVF.