2023 has been an exciting year for neuroscience as we continue to learn more about the organ that makes us who we are. As the year comes to a close, we asked our writers to share one thing that got them excited about neuroscience this year. Here’s what they said.
Lindsay Ejoh: Sensing your body in space
You have a 6th sense that you may not know about! It’s called proprioception– the sense of where your body is in space. Let me prove it to you: close your eyes and touch your thumb to the tips of each of your fingers. You would not have been able to do this without proprioception. Proprioception is crucial for maintaining balance and coordination and performing precise movements without relying on vision. To learn more about just how important this is, check out this video about the life of a man who lost his sense of proprioception. Next time you are in a situation where you must keep your balance and move around in the dark, thank your proprioceptors for not leaving you hanging..or more like leaving you falling!
Catrina Hacker: Giving a voice to patients who struggle to speak
A virtual avatar controlled by a patient’s mind is restoring their voice. Patients who lose their ability to speak after brain injury or due to neurological disorders like Amyotrophic Lateral Sclerosis (ALS) can feel isolated from the rest of the world and struggle to communicate their needs. This year, a team of neuroscientists developed a machine that uses brain activity from a patient with vocal paralysis to control an animated avatar that can speak the words the patient is thinking (watch a video here!). While there’s still lots of work to do in making these kinds of machines faster and more easily usable, this is one important step in the right direction.
Joe Stucynski: Penguin power naps
Studying how different animals sleep is a great way to help us understand its function and why we need so much of it. In a recent study, researchers tracked the sleep patterns of chinstrap penguins living in a colony in Antarctica. Surprisingly, they found that the average length of a sleep episode was only 4 seconds long, and that penguins engaged in as many as 10,000 of these mini-naps in a day! Penguins caring for eggs showed even shorter naps, indicating that this may be a strategy to stay vigilant while guarding their nests. Despite these incredibly short-but-frequent sleep episodes, chinstrap penguins still accumulate enough sleep to support their brains, allowing them to live and breed successfully. This sleep adaptation stands in stark contrast to humans and other animals who require long uninterrupted durations of sleep, and may lead to future insights into why sleep is so important.
Omer Zeliger: Artificial intelligence and language learning
With the recent boom in generative language models such as ChatGPT, a type of artificial intelligence (AI) , it’s only natural to wonder how exactly they learn to “speak” as well as they do. One group of AI researchers tracked some of these models across the learning process and, remarkably, found that the language models learn certain grammar skills in the same order that children do. We don’t know why the AIs learn these skills in this particular order, but future research aims to find out. For example, do the models learn the skills they see most often first, or do they learn in order of difficulty? Collaborations between AI and linguistics researchers have plenty to offer both fields, and studying how AIs learn language can teach us about how our brains do the same. The opposite is true too, and this research will be crucial to building better, smarter AIs – though we’re still a long ways away from any AI chipping in to do this research itself!
Sophie Liebergall: Discovery of the neurons that make you faint
If you’re among the many people who get woozy at the sight of blood or needles, you may have wondered how simply seeing something can cause physical changes so dramatic that you can even lose consciousness! This year, scientists at the University of California San Diego discovered a small subset of neurons in the brainstem that are to blame for the reflex that causes fainting. These neurons don’t just decrease heart rate and blood pressure, which are changes that have long been associated with the fainting reflex; they also send signals that directly silence the rest of the brain. The scientists were even able to make mice faint on demand by selectively activating these brainstem neurons!
Margaret Gardner: The Menstrual Cycle: Changing moods, bodies, and … our brains?!
Cramps, acne, crying way harder than we normally would over videos of animals getting adopted: those of us who get our periods can experience all sorts of changes to our bodies and emotions over a month. However, very few studies have looked at how the brain’s structure and function change over the course of the human menstrual cycle. For the last few years, Dr. Laura Pritschet and her colleagues at the University of California Santa Barbara have been making amazing breakthroughs in this field by analyzing data from a single female participant who did an MRI scan every day for 30 straight days, covering one full menstrual cycle! Their work has shown how cyclical changes in estrogen and progesterone are associated with changes in both the size of certain brain regions and the patterns of activation across the brain. This research reminds us neuroscientists that as long as we want our interpretations of the brain to be relevant to real, everyday people, hormones shouldn’t be ignored.
Kara McGaughey: New technology helps a paralyzed patient stand, walk, and more!
Spinal cord injuries damage the connecting pathways between the brain and the spinal cord, interrupting communication and resulting in permanent paralysis. This year, new technology helped a paralyzed patient stand, walk, and even climb stairs. Researchers implanted one device on the patient’s brain (over regions responsible for control/planning of leg movement) and another device on the spinal cord (over nerves responsible for controlling leg muscles). As the patient thinks about moving their legs, these signals are decoded from the device implanted in the brain and sent to the device implanted in the spinal cord, which stimulates the muscles and enables the intended movement to be performed. Not only does the system work to create a new, wireless channel of communication between the brain and the spinal cord, but it also seems to be driving recovery! The participant eventually regained the ability to walk with crutches even when the devices were switched off.
Barnes Jannuzi: Turns out, lab grown neurons just needed the right home to grow up!
Researchers have been able to grow mature human neurons by giving them a new place to hang out. Neurons have been grown in labs before, but these lab-grown human neurons look and act more similarly to neurons grown in your body because of the special environment of molecules the scientists used for the cells to grow in and around. While there is still a lot of work to be done, this really excites me because being able to grow mature human neurons could lead to massive breakthroughs in clinical neuroscience. With applications ranging from 1) neural implants for patients with neurodegeneration (like ALS or Alzheimer’s disease) or into patients with damaged spinal cords; 2) providing researchers a stable and mass-producible way to better study these neural diseases and many others. For more information please check out the original research article, or this well written ScienceDaily article.
Andrew Nguyen: Tasting with touch: sensory receptors in cephalopods
Cephalopods like the alien-like octopus and squid are known for their slippery and fluid hunting movements, quickly grappling their prey and wrestling them into submission. Previous studies have shown that these animals actually have distinct neurons in their many arms that researchers believe to operate independently of their central brain. New evidence shows that the octopus evolved new strategies to taste its prey by sensing and processing taste information locally in each arm, without the need to send the information back to the central brain first. Meanwhile, the squid has separately-evolved receptors that respond to “bitter” taste, which helps them quickly decide to pursue or avoid a particular prey. Comparing their genomes and understanding how these two cephalopod species have evolved may help explain why these two similar looking animals hunt so differently.
Stephen Wisser: Psychedelics clinic opens in Oregon
This June, the first legal psychedelics clinic opened in Eugene, Oregon. Psychedelics like magic mushrooms, which have been discussed here and here on our blog, are being studied for their therapeutic potential to treat a variety of mental health conditions like depression, addiction, and PTSD. Some of these experiments suggest psychedelics could be a helpful medicine, but until this year in Oregon, the use of psychedelics outside of a clinical trial was illegal. These clinics in Oregon and others set to open in Colorado in 2025 provide a state-regulated & relatively safe way for people to experience the drug while under the supervision of a trained professional. While not everyone agrees with this state-by-state legalization strategy, more people in more states are likely to be exposed to psychedelics through these clinics in the coming years, which will hopefully fuel the conversation about how these unique drugs could fit into our healthcare system if at all.
Serena Chen: Researchers can control ant behavior by reprogramming their brains
Ants are super social animals that do not work as individuals, but instead behave according to the needs of their colony. Their behaviors depend on their caste – a job class, such as worker or soldier – which they are born into. Different castes have distinct physical features that help them perform their job: soldier ants are stronger and have powerful mandibles to fight off predators, while workers are smaller and have mouths more suited to grabbing food. Recently, researchers found that altering certain genes in the ant brain changes their behavior, but not their physical features, so that a brute soldier now searches for food while a worker tries to fight off threats even though they are physically too weak to combat. This study shows us that what controls our genes has a major impact on who we are.
Lisa Wooldridge: Pregnant mice get new neurons with their new pups
With a few exceptions, the neurons you’ve got by early childhood are all the neurons you’ll have the rest of your life. This November, scientists discovered a new exception – the brains of mice make new scent-detecting cells during pregnancy! These baby neurons are needed for a mouse mama to sniff out and recognize her new pups. The new neurons stick around only as long as they are needed – once the pups are grown, they disappear from the mouse mama’s brain. Though It remains to be seen whether the same thing happens in human mamas, this fascinating finding is another demonstration of pregnancy’s powerful influence on the body – and expands our understanding of how and why we might add new neurons in adulthood.
Joseph Gallegos: The specialized star-shaped cells that cover your brain
One of the most unique characters in your brain is a group of cells called ‘astrocytes’ , named after their complex shapes that spread out in every direction like twinkling stars. Astrocytes are incredibly diverse in the types of jobs they have in the brain, and this year a group of astrocyte specialists at NYU defined a new unique type of astrocyte – one that covers the entire surface of your brain! These special astrocytes begin covering the outside of the brain during its development, and they are shaped almost like tree-trunks; with their arms reaching down into the brain like roots into the soil. There is still a lot to learn about the importance of this unique type of astrocyte, but they may be important for supporting the structural integrity of the brain, and to help relay messages from ‘the outside, in’. With all the new types of astrocytes we are finding in the brain, 2024 is likely to be another exciting year for astrocyte research.
Abby Lieberman: Researchers can now track neurons in freely moving, boneless animals!
Neuroscience methods developed in the last several years have made it possible to identify and study single neurons in small animals like mice. Despite these exciting tools, it has been challenging to study individual neurons in animals that have flexible boneless bodies, such as worms, because their brains move and deform inside of them! This month, a team of scientists from Harvard University and the École polytechnique fédérale de Lausanne developed a technique called Targettrack to address this challenge, using exciting artificial intelligence methods to study neurons from freely moving worms. The team also developed software so that Targettrack will be accessible to other researchers. Tools like Targettrack will make it easier for researchers to perform more ecologically-relevant studies where animals are moving freely in their environment.
Jafar Bhatti: Tracking neurons over a lifetime (of a mouse)
As technology has advanced, neuroscientists have developed new ways of measuring brain activity in behaving animals, such as mice, monkeys, and humans. However, one major challenge with measuring the activity of neurons in animals is that neural signals are usually short-lasting, due to movement of the brain or recording device. Earlier this year, scientists at Harvard developed a novel measuring device that can record the activity of single neurons across the entire adult life of mice. This new device can be implanted in brain tissue in a way that ensures minimal damage, no harmful immune response, and long-term tracking of the same single neurons. This sort of technology has the potential to improve our understanding of learning, memory, aging, and brain-computer interfaces.
We look forward to returning in 2024 for another year of sharing brain research with you all!
Cover photo by Kenta Kikuchi on Unsplash.
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