Finding a better route to treating social anxiety disorder may lie in another part of the brain, researchers suggest — ScienceDaily

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Studies have long suggested that oxytocin — a hormone that can also act as a neurotransmitter — regulates prosocial behavior such as empathy, trust and bonding, which led to its popular labeling as the “love hormone.” Mysteriously, oxytocin has also been shown to play a role in antisocial behaviors and emotions, including reduced cooperation, envy and anxiety. How oxytocin could exert such opposite roles had largely remained a mystery, but a new UC Davis study sheds light on how this may work.

Working with California mice, UC Davis researches showed that the “love hormone” oxytocin can sometimes have antisocial effects depending on where in the brain it is made. (Mark Chappell/UC Riverside)

While most oxytocin is produced in an area of the brain known as the hypothalamus, some oxytocin is produced in another brain area known as the bed nucleus of the stria terminalis, or BNST. The BNST is known for its role in the stress response, and it may play a key role in psychiatric disorders such as depression, addiction and anxiety.

The findings of the study, published this week in Proceedings of the National Academy of Sciences, show that oxytocin produced in the BNST increases stress-induced social anxiety behaviors in mice. This may provide an explanation as to why oxytocin can sometimes have antisocial effects. The lead author is Natalia Duque-Wilckens, a former doctoral researcher at UC Davis who is now at Michigan State University. The senior author is Brian Trainor, professor of psychology and director of the Behavioral Neuroendocrinology Lab at UC Davis.

“Before this study, we knew that stress increased the activity of the oxytocin-producing neurons located in the BNST, but we didn’t know if they could affect behavior. Our experiments show that production of oxytocin in the BNST is necessary for social anxiety behaviors

Results suggest retrieval of cellular powerplants via an energy feedback loop sustains communication — ScienceDaily

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Our thoughts, feelings, and movements are controlled by billions of neurons talking to each other at trillions of specialized communication points called synapses. In an in-depth study of neurons grown in laboratory petri dishes, National Institutes of Health researchers discovered how the chattiest of some synapses find the energy to support intense conversations thought to underlie learning and memory. Their results, published in Nature Metabolism, suggest that a series of chemical reactions control a feedback loop that senses the need for more energy and replenishes it by recruiting cellular powerplants, called mitochondria, to the synapses. The experiments were performed by researchers in a lab led by Zu-Hang Sheng, Ph.D., at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS).

The team studied synapses that use the neurotransmitter glutamate to communicate. Communication happens when a packet of glutamate is released from presynaptic boutons which are tiny protrusions that stick out, like beads on a string, of long, wiry parts of neurons called axons. Previously, Dr. Sheng’s team showed that synaptic communication is an energy-demanding process and that mitochondria traveling along axons can control signals sent by boutons. Boutons that had mitochondria sent stronger and more consistent signals than those that were missing powerplants. The difference was due to higher energy levels produced by the mitochondria in the form of ATP.

In this study, led by Sunan Li, Ph.D., a post-doctoral fellow at NINDS, the team investigated what happens when boutons undergo intense communication thought to underlie learning and memory. They found that this type of signaling quickly dropped energy levels at boutons. These changes triggered a series of chemical reactions controlled by an energy sensor called AMP-activated protein kinases (AMPK) that ultimately led to the rapid recruitment of mitochondria to the boutons. Genetically blocking or chemically interfering with this

Recent findings suggest the repeated evolution of similar traits in island lizards was not channelled by developmental responses to the environment, as commonly thought — ScienceDaily

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Scientists have challenged a popular theory behind the evolution of similar traits in island lizards, in a study published recently in eLife.

The findings in Greater Antillean Anolis lizards provide insights on why creatures often evolve similar physical features independently when living in similar habitats. They suggest that the role of developmental plasticity in shaping adaptive evolution may be less important than commonly thought.

Developmental plasticity refers to how development responds to the environment, in particular the way that an organism’s genetic constitution (or genotype) interacts with its environment during development to produce a particular set of characteristics (or phenotype).

“Anolis lizards that live on all four of the Greater Antillean islands have independently and repeatedly evolved six different body types for maneuvering through their given habitat,” says lead author Nathalie Feiner, Researcher at the Department of Biology, Lund University, Sweden. “As a result, they make a great model for studying why evolution often repeats itself.”

To address this question, Feiner and the team used micro computed tomography scans to measure the shoulder, hip and leg bones of 95 species of anoles that live on the Greater Antillean islands. Their work revealed that several of the species’ body shapes evolved along similar trajectories.

“These body shapes are adapted by natural selection, but several different shapes could in principle perform equally well in a given habitat,” says senior author Tobias Uller, Professor of Evolutionary Biology at the Department of Biology, Lund University. “As a result, repeated evolution is more likely to occur when species share a developmental biology that makes some characteristics appear readily, while others are rare or even impossible.”

One source of these developmental biases can be found in how individuals respond to different environments, a hypothesis known as plasticity-led evolution. The researchers tested how the anoles’ bones

Compact Nuclear Fusion Reactor Is ‘Very Likely to Work,’ Studies Suggest

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Scientists developing a compact version of a nuclear fusion reactor have shown in a series of research papers that it should work, renewing hopes that the long-elusive goal of mimicking the way the sun produces energy might be achieved and eventually contribute to the fight against climate change.

Construction of a reactor, called Sparc, which is being developed by researchers at the Massachusetts Institute of Technology and a spinoff company, Commonwealth Fusion Systems, is expected to begin next spring and take three or four years, the researchers and company officials said.

Although many significant challenges remain, the company said construction would be followed by testing and, if successful, building of a power plant that could use fusion energy to generate electricity, beginning in the next decade.

This ambitious timetable is far faster than that of the world’s largest fusion-power project, a multinational effort in Southern France called ITER, for International Thermonuclear Experimental Reactor. That reactor has been under construction since 2013 and, although it is not designed to generate electricity, is expected to produce a fusion reaction by 2035.

Bob Mumgaard, Commonwealth Fusion’s chief executive and one of the company’s founders, said a goal of the Sparc project was to develop fusion in time for it to play a role in mitigating global warming. “We’re really focused on how you can get to fusion power as quickly as possible,” he said.

Fusion, in which lightweight atoms are brought together at temperatures of tens of millions of degrees to release energy, has been held out as a way for the world to address the climate-change implications of electricity production.

Like a conventional nuclear fission power plant that splits atoms, a fusion plant would not burn fossil fuels and would not produce greenhouse-gas emissions. But its fuel, usually isotopes of hydrogen, would

Researchers suggest providing mental health services to those with the greatest need — ScienceDaily

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Experiencing multiple stressors triggered by the COVID-19 pandemic — such as unemployment — and COVID-19-related media consumption are directly linked to rising acute stress and depressive symptoms across the U.S., according to a groundbreaking University of California, Irvine study.

The report appears in Science Advances, published by the American Association for the Advancement of Science.

“The pandemic is not hitting all communities equally,” said lead author E. Alison Holman, UCI professor of nursing. “People have lost wages, jobs and loved ones with record speed. Individuals living with chronic mental and physical illness are struggling; young people are struggling; poor communities are struggling. Mental health services need to be tailored to those most in need right now.”

In addition, the research highlights the connection between mental health and exposure to media coverage of the COVID-19 pandemic, suggesting the need to step away from the television, computer or smartphone to protect psychological well-being.

“The media is a critical source of information for people when they’re faced with ambiguous, ongoing disasters,” said Roxane Cohen Silver, professor of psychological science and one of the study’s principal investigators. “But too much exposure can be overwhelming and lead to more stress, worry and perceived risks.”

With funding from a National Science Foundation RAPID grant, Holman, Silver, and co-investigators Dana Rose Garfin and Rebecca R. Thompson conducted a national survey of more than 6,500 U.S. residents in March and April 2020, as illness and deaths were rising around the country. Using the NORC AmeriSpeak panel, the study was the first of its kind to examine early predictors of rising mental health problems across the nation. The design let researchers evaluate the effects of the pandemic as it was unfolding in real time.

“Over the course of the study, the size of the pandemic shifted dramatically,” Holman