Smparticle2 - Untitled

“She has autonomy. She has a strong will. But she can’t move. So in many ways her life is my life. It’s bigger than me, it controls me, and it makes me fight like never before. We spend so much time together that she’s a part of me. She knows how important she is to me. She had childhood cancer. Her heart failed three times. And I was by her side the entire time. I never realized that I could love someone as much as this. She could never hurt me. She could never hurt anyone. We always ask her: ‘Are you angry?’, ‘Are you mad?’ And she always says ‘no.’ She laughs when I laugh. And right now I’m trying not to cry. Because she’ll cry if I cry.” (São Paulo, Brazil)

Big Improvements to Brain-Computer Interface

When people suffer spinal cord injuries and lose mobility in their limbs, it’s a neural signal processing problem. The brain can still send clear electrical impulses and the limbs can still receive them, but the signal gets lost in the damaged spinal cord.

The Center for Sensorimotor Neural Engineering (CSNE)—a collaboration of San Diego State University with the University of Washington (UW) and the Massachusetts Institute of Technology (MIT)—is working on an implantable brain chip that can record neural electrical signals and transmit them to receivers in the limb, bypassing the damage and restoring movement. Recently, these researchers described in a study published in the journal Nature Scientific Reports a critical improvement to the technology that could make it more durable, last longer in the body and transmit clearer, stronger signals.

The technology, known as a brain-computer interface, records and transmits signals through electrodes, which are tiny pieces of material that read signals from brain chemicals known as neurotransmitters. By recording brain signals at the moment a person intends to make some movement, the interface learns the relevant electrical signal pattern and can transmit that pattern to the limb’s nerves, or even to a prosthetic limb, restoring mobility and motor function.

The current state-of-the-art material for electrodes in these devices is thin-film platinum. The problem is that these electrodes can fracture and fall apart over time, said one of the study’s lead investigators, Sam Kassegne, deputy director for the CSNE at SDSU and a professor in the mechanical engineering department.

Kassegne and colleagues developed electrodes made out of glassy carbon, a form of carbon. This material is about 10 times smoother than granular thin-film platinum, meaning it corrodes less easily under electrical stimulation and lasts much longer than platinum or other metal electrodes.

“Glassy carbon is much more promising for reading signals directly from neurotransmitters,” Kassegne said. “You get about twice as much signal-to-noise. It’s a much clearer signal and easier to interpret.”

The glassy carbon electrodes are fabricated here on campus. The process involves patterning a liquid polymer into the correct shape, then heating it to 1000 degrees Celsius, causing it become glassy and electrically conductive. Once the electrodes are cooked and cooled, they are incorporated into chips that read and transmit signals from the brain and to the nerves.

Researchers in Kassegne’s lab are using these new and improved brain-computer interfaces to record neural signals both along the brain’s cortical surface and from inside the brain at the same time.

“If you record from deeper in the brain, you can record from single neurons,” said Elisa Castagnola, one of the researchers. “On the surface, you can record from clusters. This combination gives you a better understanding of the complex nature of brain signaling.”

A doctoral graduate student in Kassegne’s lab, Mieko Hirabayashi, is exploring a slightly different application of this technology. She’s working with rats to find out whether precisely calibrated electrical stimulation can cause new neural growth within the spinal cord. The hope is that this stimulation could encourage new neural cells to grow and replace damaged spinal cord tissue in humans. The new glassy carbon electrodes will allow her to stimulate, read the electrical signals of and detect the presence of neurotransmitters in the spinal cord better than ever before.

Cool! Go theoretical -and experimental-physics!

Heating up exotic topological insulators

Fashion is changing in the avant-garde world of next-generation computer component materials. Traditional semiconductors like silicon are releasing their last new lines. Exotic materials called topological insulators (TIs) are on their way in. And when it comes to cool, nitrogen is the new helium.

This was clearly on display in a novel experiment at the National Institute of Standards and Technology (NIST) that was performed by a multi-institutional collaboration including UCLA, NIST and the Beijing Institute of Technology in China.

Topological insulators are a new class of materials that were discovered less than a decade ago after earlier theoretical work, recognized in the 2016 Nobel Prize in physics, predicted they could exist. The materials are electrical insulators on the inside and they conduct electricity on the outer surface. They are exciting to computer designers because electric current travels along them without shedding heat, meaning components made from them could reduce the high heat production that plagues modern computers. They also might be harnessed one day in quantum computers, which would exploit less familiar properties of electrons, such as their spin, to make calculations in entirely new ways. When TIs conduct electricity, all of the electrons flowing in one direction have the same spin, a useful property that quantum computer designers could harness.

Read more.

“It is the most passionate relationship of the film. It is almost equivalent to that of Scarlett O’hara and Ashley Wilkes and Scarlett and Rhett Butler. Mammy is Scarlett’s true mother. It is Mammy to whom Scarlett goes to for advice, it is Mammy who sees deeply into Scarlett’s emotions and knows everything that’s going on with her. Whereas Scarlett’s biological mother doesn’t understand the emotional turmoil of her daughter. This is an incredible performance, very inflictive, that unfortunately is never getting discussed these days because of the sensitivity we should properly feel.” -Camille Paglia

A research group at MIT has created a new class of fast-acting, soft robots from hydrogels. The robots are activated by pumping water in or out of hollow, interlocking chambers; depending on the configuration, this can curl or stretch parts of the robot. The hydrogel bots can move quickly enough to catch and release a live fish without harming it. (Which is a feat of speed I can’t even manage.) Because hydrogels are polymer gels consisting primarily of water, the robots could be especially helpful in biomedical applications, where their components may be less likely to be rejected by the body. For more, see MIT News or the original paper. (Image credit: H. Yuk/MIT News, source; research credit: H. Yuk et al.)

Insecticides Mimic Melatonin, Creating Higher Risk of Diabetes

Synthetic chemicals commonly found in insecticides and garden products bind to the receptors that govern our biological clocks, University at Buffalo researchers have found. The research suggests that exposure to these insecticides adversely affects melatonin receptor signaling, creating a higher risk for metabolic diseases such as diabetes.

The research is in Chemical Research in Toxicology. (full access paywall)

Kootenai Falls, Montana by Liang Ge

Researchers identify method of creating long-lasting memories

Imagine if playing a new video game or riding a rollercoaster could help you prepare for an exam or remember other critical information.

A new study in mice shows this link may be possible.

Attention-grabbing experiences trigger the release of memory-enhancing chemicals. Those chemicals can etch memories into the brain that occur just before or soon after the experience, regardless of whether they were related to the event, according to researchers at UT Southwestern Medical Center’s Peter O’Donnell Jr. Brain Institute.

The findings, published in Nature, hold intriguing implications for methods of learning in classrooms as well as an array of potential uses in the workplace and personal life, researchers said.

The trick to creating long-lasting memories is to find something interesting enough to activate the release of dopamine from the brain’s locus coeruleus (LC) region.

“Activation of the locus coeruleus increases our memory of events that happen at the time of activation and may also increase the recall of those memories at a later time,” said Dr. Robert Greene, the study’s co-senior author and a Professor of Psychiatry and Neurosciences with the O’Donnell Brain Institute.

The study explains at the molecular level why people tend to remember certain events in their lives with particular clarity as well as unrelated details surrounding those events: for instance, what they were doing in the hours before the Sept. 11, 2001, terrorist attacks; or where they were when John F. Kennedy was assassinated.

“The degree to which these memories are enhanced probably has to do with the degree of activation of the LC,” said Dr. Greene, holder of the Sherry Gold Knopf Crasilneck Distinguished Chair in Psychiatry, in Honor of Mollie and Murray Gold, and the Sherry Knopf Crasilneck Distinguished Chair in Psychiatry, in Honor of Albert Knopf. “When the New York World Trade Center came down on 9/11, that was high activation.”

But life-changing events aren’t the only way to trigger the release of dopamine in this part of the brain. It could be as simple as a student playing a new video game during a quick break while studying for a crucial exam, or a company executive playing tennis right after trying to memorize a big speech.

“In general, anything that will grab your attention in a persistent kind of way can lead to activation,” Dr. Greene said.

Scientists have known dopamine plays a large role in memory enhancement, though where the chemical originates and how it’s triggered have been points of study over the years.

Dr. Greene led a study published in 2012 that identified the locus coeruleus as a third key source for dopamine in the brain, besides the ventral tegmental area and the substantia nigra. That research demonstrated the drug amphetamine could pharmacologically trigger the brain’s release of dopamine from the LC.

The latest study builds upon those findings, establishing that dopamine in this area of the brain can be naturally activated through behavioral actions and that these actions enhance memory retention.

The new study suggests that drugs targeting neurons in the locus coeruleus may affect learning and memory as well. The LC is located in the brain stem and has a range of functions that affect a person’s emotions, anxiety levels, sleep patterns, memory and other aspects of behavior.

The study tested 120 mice to establish a link between locus coeruleus neurons and neuronal circuits of the hippocampus – the region of the brain responsible for recording memories – that receive dopamine from the LC.

One part of the research involved putting the mice in an arena to search for food hidden in sand that changed location each day. The study found that mice that were given a “novel experience” – exploring an unfamiliar floor surface 30 minutes after being trained to remember the food location – did better in remembering where to find the food the next day.

Researchers correlated this memory enhancement to a molecular process in the brain by injecting the mice with a genetically encoded light-sensitive activator called channelrhodopsin. This sensor allowed them to selectively activate dopamine-carrying neurons of the locus coeruleus that go to the hippocampus and to see first-hand which neurons were responsible for the memory enhancement.

They found that selectively activating the channelrhodopsin-labeled neurons with blue light (a technique called optogenetics) could substitute for the novelty experience as a memory enhancer in mice. They also found that this activation could cause a direct, long-lasting synaptic strengthening – an enhancement of memory-relevant communication occurring at the junctions between neurons in the hippocampus. This process can mediate improvement of learning and memory.

Some next steps include investigating how big an impact this finding can have on human learning, whether it can eventually lead to an understanding of how patients can develop failing memories, and how to better target effective therapies for these patients, said Dr. Greene.