Superagers maintain exceptional memory by growing new hippocampal neurons at twice the rate of their peers.
Category: neuroscience
A common parasite in the brain is far more active than we thought
A parasite carried by billions isn’t dormant at all—it’s running a secret survival operation inside the brain.
A common parasite long thought to lie dormant is actually much more active and complex. Researchers found that Toxoplasma gondii cysts contain multiple parasite subtypes, not just one sleeping form. Some are primed to reactivate and cause disease, which helps explain why infections are so hard to treat. The discovery could reshape efforts to develop drugs that finally eliminate the parasite for good.
An ultrasound-scanning in vivo light source
Beautifully executed paper on putting mechanoluminescent nanoparticles into blood circulation of mice which express optogenetic channels. Focused ultrasound can then trigger targeted light emission and control of neural activity in the brain and elsewhere.
A deep-tissue light source made from mechanoluminescent transducers stimulated by focused ultrasound enables wide imaging of live animal vasculature, and modulation of neuronal activity and behaviour.
Ultrafast MRI uncovers brain signal direction: New scan may help decode autism, Alzheimer’s and hallucinations
Researchers at the Champalimaud Foundation in Lisbon have for the first time managed to identify with an imaging technique whether nervous impulses in the brain of rats are flowing in a “bottom-up” (feedforward), carrying information about visual input, or a “top-down” (feedback) direction, carrying information about expectations or predictions on a given task or about the perception of the world around us. Their results, published in Nature Communications, could have important implications for understanding changes in the brains of people with hallucinations, Alzheimer’s, schizophrenia, autism, and other conditions.
Joana Carvalho, first author of the new study, who at the time was working in the Preclinical MRI lab led by senior author Noam Shemesh (she has since become a group leader at Coimbra University), “came up with the ideas, did the experiments and analyzed the results. I just brought the MRI expertise,” says Shemesh good-humoredly. Co-author Koen V. Haak from Tilburg University (Netherlands) gave assistance with the computational models and the others helped with the experiments.
The team showed that spontaneous feedforward and feedback nervous impulses in these rodents (the brain never sleeps) each have a unique, distinct signature, which can be detected by using a method they developed, called uFLARE (UltraFast Layer-Resolved Encoding), a neuroimaging technique designed to map brain activity with unprecedented high temporal and spatial resolutions.
Two to tango: Study shows dancers’ brains sync up as they move together
Scientists at the University of Colorado Boulder have discovered something that experienced ballroom dancers have long known: When dancers are in tune with each other, their brains may sync up, helping them move as one.
“When we dance, our brains are actually coupling,” said Thiago Roque, a graduate student in the Atlas Institute who led the study. “We are synchronizing our brains through our behavior.”
For the unique experiment, the researchers placed electroencephalogram (EEG) caps, or devices that measure electrical activity in the brain, on pairs doing the Argentine Tango—a sensuous dance where a leader and follower hold each other tight while moving together to music.
The brain may use dopamine to bend time and shape memory
Ever heard of getting a “dopamine hit” from something you enjoy? These exciting moments also appear to influence memory, although perhaps not in the way you’d expect.
New research by UCLA psychologists suggests your brain may use dopamine to distort and expand time between distinct events, separating the flow of experience into pieces that can be flexibly reconstructed in the future.
The study, published in Nature Communications, found that a key dopamine-producing area of the brain—the ventral tegmental area—was activated when volunteers participating in an MRI scan detected the start of a new event. Importantly, when this dopamine hub was strongly activated, people reported more time had passed. The researchers also found that when people blinked more during a new event—an action thought to be related to dopamine signaling—their memory for time once again expanded.
The Most Counterintuitive Way to Build a Brain
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The Neuroscience Behind Adversarial Convergence and How It Can Influence AI Design
In a previous article, I traced Adversarial Convergence (AC) through 2,500 years of human intellectual history — from Sun Tzu’s unsentimental assessment of self and enemy, through Socrates’ elenchus, through Hegel’s dialectic, and to Kant’s critical method. The argument was that AC isn’t a novel prompt engineering technique. It’s a formalization of something human cognition has been doing naturally whenever it operates at points of tension and resolution.
This raises a deeper question: why does structured adversarial reasoning consistently produce more refined analysis and conclusions? What is it about human cognitive architecture that makes this particular structure the natural shape of rigorous truth-seeking? The answer appears to live, at least in part, in a small but remarkably important region of the brain.
Brain motion is driven by mechanical coupling with the abdomen
UNIVERSITY PARK, Pa. — The brain is more mechanically connected to the body than previously appreciated, scientists reported today (April 27) in Nature Neuroscience. Through a study using mice and simulations, the team found a potential biological mechanism underlying why exercise is thought to benefit brain health: abdominal contractions compress blood vessels connected to the spinal cord and the brain, enabling the organ to gently move within the skull. This swaying facilitates the surrounding cerebrospinal fluid to flow over the brain, potentially washing away neural waste that could cause problems for brain function.
According to Patrick Drew, professor of engineering science and mechanics, of neurosurgery, of biology and of biomedical engineering at Penn State, the work builds on previous studies detailing how sleep and neuron loss can influence how and when cerebrospinal fluid flushes through the brain.
“Our research explains how just moving around might serve as an important physiological mechanism promoting brain health,” said Drew, corresponding author on the paper. “In this study, we found that when the abdominal muscles contract, they push blood from the abdomen into the spinal cord, just like in a hydraulic system, applying pressure to the brain and making it move. Simulations show that this gentle brain movement will drive fluid flow in and around the brain. It is thought the movement of fluid in the brain is important for removing waste and preventing neurodegenerative disorders. Our research shows that a little bit of motion is good, and it could be another reason why exercise is good for our brain health.”
Drew, who also holds the title of associate director of the Huck Institutes of the Life Sciences, explained how in a hydraulic system, a pump creates pressure that drives fluid flow. In this case, the pump is the abdominal contraction — which can be as light as the tensing prior to sitting up or taking a step. The contraction puts pressure on the vertebral venous plexus, a network of veins that connect the abdominal cavity to the spinal cavity, causing the brain to move.
Abstract: Nature Neuroscience Brain motion is driven by mechanical coupling with the abdomen.
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