An amazing graph theoretic analysis of the C. elegans neuropeptide connectome!
Neuromodulation by peptides is essential for brain function. By comprehensively mapping neuropeptide signaling in the nematode C. elegans, Ripoll-Sánchez et al. define a dense wireless network whose organization differs in important ways from wired brain circuits. This network is a prototype for understanding neuropeptide signaling networks in larger brains.
A study revealed that one-third of cardiac arrest survivors experienced consciousness, with EEG showing brain activity despite heart stoppage. This groundbreaking finding challenges current understandings of brain function during cardiac emergencies.
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My name is Artem, I’m a computational neuroscience student and researcher. In this video we discuss engrams – fundamental units of memory in the brain. We explore what engrams are, how memory is allocated, where it is stored, and how different memories become linked with each other.
OUTLINE: 00:00 — Introduction. 00:39 — Historical background. 01:44 — Fear conditioning paradigm. 03:38 — Immediate-early genes as memory markers. 08:13 — Engrams are necessary and sufficient for recall. 10:16 — Excitabiliy and memory allocation. 16:19 — Brain-wide engrams. 18:12 — Linking memories together. 24:20 — Summary. 25:33 — Brilliant. 27:09 — Outro.
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Georgetown University Medical Center neuroscientists revealed that the fusiform face area, a vital region for face processing in sighted people, plays an important role in helping blind people recognize faces.
Cleveland Clinic researchers analyzed genes and brain tissue of patients with Alzheimer’s and found that differences in brain immunometabolism – the interactions between the immune system and the ways cells create energy – may contribute to women’s increased risk for the disease and its severity.
The findings, published in Alzheimer’s and Dementia, offer important insight into developing sex-specific treatment and prevention options for Alzheimer’s disease, the sixth-leading cause of death in the United States.
“Our immune systems depend on communication between different cell types in our bodies, which are fueled by energy created from unique metabolic processes,” said Justin Lathia, Ph.D., vice chair of the Department of Cardiovascular and Metabolic Sciences and co-author on the paper. “As sex influences both the immune system and metabolic process, our study aimed to identify how all of these individual factors influence one another to contribute to Alzheimer’s disease.”
Contrary to popular belief, the brain does not have the capability to rewire itself to compensate for loss of sight, amputations, or stroke-related damage, according to scientists from the University of Cambridge and Johns Hopkins University.
In a recent paper published in eLife, Professors Tamar Makin (Cambridge) and John Krakauer (Johns Hopkins) argue that the notion that the brain, in response to injury or deficit, can reorganize itself and repurpose particular regions for new functions, is fundamentally flawed – despite being commonly cited in scientific textbooks. Instead, they argue that what is occurring is merely the brain being trained to utilize already existing, but latent, abilities.
Researchers in Texas have developed a method to keep a brain alive and functioning for several hours without being connected to the body — a truly weird scientific experiment that recalls the head in jars bit in the iconic cartoon “Futurama.”
A team led by the University of Texas Southwestern Medical Center in Dallas took two pigs and severed connections between their heads and bodies, instead hooking the brains up to a device they call the extracorporeal pulsatile circulatory control (EPCC), which they detailed in a paper published in the journal Scientific Reports. The machine keeps blood pumping through the brain, mimicking the natural flow when it’s connected to the rest of the body.
The intent behind this nightmarish procedurewas to study the brain independently from other bodily functions that may influence it, but the system may also lead to better-designed cardiopulmonary bypass, a process in which machines take over your heart and lung function during surgery.
A recent study has raised questions about the impact of chronic caffeine consumption on our brain’s ability to adapt and learn. In a new study published in Frontiers in Psychiatry, scientists found that long-term caffeine users may exhibit decreased brain plasticity, a critical factor in the processes of learning and memory, when subjected to a brain stimulation protocol.
Caffeine is a common stimulant found in coffee, tea, soda, and other beverages. It’s known to help with alertness and concentration, but its effects on the brain’s ability to change and adapt over time, a process called plasticity, have been less clear.
Previous studies have shown mixed results when it comes to caffeine’s influence on brain plasticity. Some studies hinted that caffeine might hinder the brain’s ability to learn and adapt, while others suggested potential benefits. The researchers conducted this study to investigate the effects of caffeine on human brain plasticity, specifically focusing on its impact on long-term potentiation (LTP) and its potential interaction with a neuromodulation technique called repetitive transcranial magnetic stimulation (rTMS).
In 2018, Groh’s team discovered that the ears make a subtle, imperceptible noise when the eyes move. In a new report appearing the week of November 20 in the journal Proceedings of the National Academy of Sciences, the Duke team now shows that these sounds can reveal where your eyes are looking.
It also works the other way around. Just by knowing where someone is looking, Groh and her team were able to predict what the waveform of the subtle ear sound would look like.
These sounds, Groh believes, may be caused when eye movements stimulate the brain to contract either middle ear muscles, which typically help dampen loud sounds, or the hair cells that help amplify quiet sounds.
In a recent study published in Nature Communications, researchers aimed to develop a model of rumination, a mental process characterized by persistent negative self-reflective thoughts that can lead to depression and anxiety. Using resting-state functional magnetic resonance imaging (rsfMRI) — a technique that captures brain activity when a person is at rest — they identified a specific region of the brain, the dorsal medial prefrontal cortex (dmPFC), as playing a pivotal role in these ruminative thoughts.
Recognizing that rumination can be an early risk factor for depression, the researchers aimed to develop methods for subclinical detection and intervention before clinical episodes of depression occur. Early detection and intervention can be crucial for preventing the development of more severe mental health conditions.
The default mode network (DMN), a large-scale resting-state network, had been consistently linked to rumination in previous research. But the precise brain regions responsible for variations in individual levels of rumination have remained elusive. The researchers wanted to investigate the specific role of the DMN and its subsystems in rumination, as it is involved in various processes related to self-referential thought, autobiographical memory, emotional experience, and more.