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Nov 12, 2019

Specific neurons that map memories now identified in the human brain

Posted by in categories: biotech/medical, engineering, neuroscience, virtual reality

An important aspect of human memory is our ability to conjure specific moments from the vast array of experiences that have occurred in any given setting. For example, if asked to recommend a tourist itinerary for a city you have visited many times, your brain somehow enables you to selectively recall and distinguish specific memories from your different trips to provide an answer.

Studies have shown that —the kind of you can consciously recall like your home address or your mother’s name—relies on healthy medial temporal lobe structures in the , including the hippocampus and entorhinal cortex (EC). These regions are also important for spatial cognition, demonstrated by the Nobel-Prize-winning discovery of “place cells” and “grid cells” in these regions— that activate to represent specific locations in the environment during navigation (akin to a GPS). However, it has not been clear if or how this “spatial map” in the brain relates to a person’s memory of events at those locations, and how in these regions enables us to target a particular memory for retrieval among related experiences.

A team led by neuroengineers at Columbia Engineering has found the first evidence that in the human brain target specific memories during recall. They studied recordings in neurosurgical patients who had electrodes implanted in their brains and examined how the patients’ brain signals corresponded to their behavior while performing a virtual-reality (VR) object-location memory task. The researchers identified “memory-trace cells” whose activity was spatially tuned to the location where subjects remembered encountering specific objects. The study is published today in Nature Neuroscience.

Nov 11, 2019

SpaceX launch highlights threat to astronomy from ‘megaconstellations’

Posted by in categories: internet, satellites

Spaceflight company SpaceX is set to launch 60 communications satellites into orbit today as the basis for a web of spacecraft designed to provide global Internet access. But many astronomers worry that such ‘megaconstellations’ — which are also planned by other companies that could launch tens of thousands of satellites in the coming years — might interfere with crucial observations of the Universe. They fear that megaconstellations could disrupt radio frequencies used for astronomical observation, create bright streaks in the night sky and increase congestion in orbit, raising the risk of collisions.


Researchers fear that plans to send tens of thousands of communications satellites into orbit will disrupt scientific observations of the Universe.

Nov 11, 2019

2019 Mercury Transit

Posted by in category: space

Q: What did Mercury say when it was asked to line up between Earth and the Sun?

A: I’ll pass! 😎

We were in for a rare treat during today’s #MercuryTransit, which only happens about 13 times a century! Revel in the views captured our NASA Sun Science-observing satellite in a variety of a variety of wavelengths of light in the extreme ultraviolet: https://go.nasa.gov/2NF6tQQ

Nov 11, 2019

The U.S. military, algorithmic warfare, and big tech

Posted by in categories: information science, military, robotics/AI

The U.S. military is preparing for the age of AI and algorithmic warfare, and it’s getting help from tech giants like Facebook, Google, and Microsoft.

Nov 11, 2019

Natural image reconstruction from brain waves: a novel visual BCI system with native feedback

Posted by in category: neuroscience

Here we hypothesize that observing the visual stimuli of different categories trigger distinct brain states that can be decoded from noninvasive EEG recordings. We introduce an effective closed-loop BCI system that reconstructs the observed or imagined stimuli images from the co-occurring brain wave parameters. The reconstructed images are presented to the subject as a visual feedback. The developed system is applicable to training BCI-naïve subjects because of the user-friendly and intuitive way the visual patterns are employed to modify the brain states.

Currently, the usage of EEG-based BCIs in assistive and rehabilitation devices mostly comes down to the following scenarios:

Nov 11, 2019

The Important Gut-Behavior Relationship

Posted by in categories: biotech/medical, existential risks, neuroscience

Both humans and mice respond to fear in ways that are deeply etched in survival mechanisms that have evolved over millions of years. Feeling afraid is part of a response that helps us to survive; we learn to respond appropriately, based on our assessment of the danger we face. Importantly, part of this response involves extinguishing fear and modifying our behavior accordingly, once we have learned that a potential threat poses little or no imminent danger. The inability to adapt to fears or lay them aside is involved in disorders such as PTSD and anxiety.

The researchers from Weill Cornell demonstrated that changes in the microbiome can result in an impaired ability to extinguish fear. This was true of two groups of mice: one group had been treated with antibiotics; the other group was raised entirely free of germs. The ability of both groups of mice to extinguish fear was compared with that of control mice whose microbiome was not altered. The difference suggested that signals from the microbiome were necessary for optimal extinction of conditioned fear responses.

Nov 11, 2019

The people on a mission to live for ever – video

Posted by in category: life extension

What if you could cheat death and live for ever? To people in the radical life extension movement, immortality is a real possibility. Leah Green spends a long weekend at RAADfest, a meeting of scientists, activists and ordinary people who want to extend the human lifespan. So is reversing your age a real possibility? And what’s behind the wish for immortality?

Nov 11, 2019

Previously Unseen Phase of Matter Produced by Ultrafast Laser Pulses

Posted by in categories: energy, physics

Adding energy to any material, such as by heating it, almost always makes its structure less orderly. Ice, for example, with its crystalline structure, melts to become liquid water, with no order at all.

But in new experiments by physicists at MIT and elsewhere, the opposite happens: When a pattern called a charge density wave in a certain material is hit with a fast laser pulse, a whole new charge density wave is created — a highly ordered state, instead of the expected disorder. The surprising finding could help to reveal unseen properties in materials of all kinds.

The discovery is being reported today (November 11, 2019) in the journal Nature Physics, in a paper by MIT professors Nuh Gedik and Pablo Jarillo-Herrero, postdoc Anshul Kogar, graduate student Alfred Zong, and 17 others at MIT, Harvard University, SLAC National Accelerator Laboratory, Stanford University, and Argonne National Laboratory.

Nov 11, 2019

CRISPR: the movie

Posted by in categories: biotech/medical, education, genetics

New gene-editing documentary showcases biology’s hottest tool — up to the point when things went awry. By Amy Maxmen.

Nov 11, 2019

How Long Before Sodium Batteries Are Worth Their Salt?

Posted by in categories: chemistry, computing, mobile phones, transportation

Circa 2017


Today, lithium is the active ingredient in batteries that power smart phones, laptops, and cars. But because of the price of lithium, researchers have been looking for another, more abundant element that could replace it. Several start-ups and established companies have tackled the idea of developing rechargeable batteries in which the active ingredient is sodium, lithium’s neighbor on the periodic table.

Besides its availability, sodium has several other important properties—not the least of which is its resistance to catching on fire. What’s more, “It was a good candidate because it could store a similar amount of energy as compared to lithium,” remembers Minah Lee, who does research on sodium batteries at Stanford University.

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