2023's Biggest Breakthroughs in Biology and Neuroscience

The line between imagination and reality has long been the realm of cinematic and literary exploration. But now, thanks to research published in

2023

, scientists are gaining new insights into one of the most mysterious transitions in human consciousness: the shift from reality-based perception to internal, imaginative brain states. Imagination really allows you to think about what things would be like in alternate realities, which is a really powerful thing. It can help you plan things. Can you imagine, okay, if I go to dinner, what will it taste like? If that's something I like? Okay, so let me go make that for dinner, for example.

This allows you to really enjoy and plan for your future. It's interesting to know how the brain distinguishes internally generated content from material that exists in the world. But scientists have long struggled to understand the puzzling

neuroscience

behind our ability to distinguish between perception and imagination, since both use many of the same parts of the brain. In 1910, psychologist Mary Perky was attempting to develop a scientific definition of imagination. She then devised an experiment that produced a surprising result. Test subjects were asked to stare at a blank wall and imagine a certain fruit. Meanwhile, behind the scenes, Perky projected a very faint image of the fruit on the wall.

When asked if they had seen anything real, participants said no, although they commented on how vivid the image they were imagining seemed. Perky concluded that when our perception of something matches what we imagine, we will assume that we have imagined it. This would eventually become known as the Perky effect. Since then, there have been several studies that attempted to replicate it, but the results were very mixed. However, decades with the advancement of neuroimaging, we have shown time and time again that when we imagine something, many of the same brain processes are engaged as when we would actually see the same thing.

So Dykstra and her team designed an updated version of Perky's experiment. The setup was similar. But to better control for variability in imagined objects, the researchers asked participants to imagine something more specific: diagonal lines. Participants looked at a static screen and were asked to imagine the lines, just as in Perky's experiment, faint images appeared and disappeared. What we found was actually somewhat surprising because we didn't find a Perky effect. However, in the results published in

2023

, a more nuanced picture emerged. When the researchers asked the participants whether the lines they saw were real or imaginary, the answers varied.

When they were shown faint images of the lines. Participants were more likely to report seeing them and when they were not shown the lines. some still reported seeing them, suggesting vivid imaginings at work. All in all, what we can conclude from this is that when imagination becomes really vivid, it can become confused with reality. So the way we're thinking about this now is that this is all about sensory force. Unlike cheerful, Dykstra went beyond first-person reporting. She and her collaborators analyzed neuroimaging data from the participants in their study. What they saw suggests that the visual and prefrontal cortices may be directly involved in the process of distinguishing imagination from reality.

So intuitively I always thought it would be more of a switch. But research seems to suggest it might be more of a gradual meter. But the way you interpret this is more binary. So once it crosses some threshold, you think, now it's real, and before it's not real. And that point is what we call the threshold of reality. And they are basically saying that the way we distinguish what is seen from what is imagined is the strength of this representation. It has to overcome the threshold for us to consider it real or existing in the world.

And that's something we're very interested in investigating further, if we can measure this in individual people and then see if it relates to things like propensity for hallucinations or schizophrenia or sometimes in Parkinson's, People experience these really vivid hallucinations that are actually imaginations, but they feel real to these people. So one hypothesis would be that something is wrong at your threshold of reality the more I learn, the more questions I have, and the more I want to move forward. Human beings are made up of almost 70 trillion cells, but only half of them are truly ours. The other half are foreign microbes, collectively called the human microbiome.

Covering us inside and out, this intricate ecosystem helps us digest food and fight disease. Although the microbiome is an essential part of who we are, it remains largely a mystery to science. Researchers have been trying to better understand how we acquire these foreign microbes and whether they are freely exchanged between people like other germs. That's why we say microbiome, but this means many different species, hundreds to thousands. So it's not just about studying one pathogen, we have to study many microorganisms, all of them are different. These organisms vary in terms of their genomes, their functions, what they do, why they are there, how they interact with the human body.

And that presents many different challenges: how to grow these organisms, how to study their different and varied functions. There is another reason why our microbiome is complicated to study. Its inhabitants change constantly. At birth we have an imprint of the bacteria in and around the environment. And then we continually update, improve, change and modify our microbiome throughout our lives. This year, a team of biologists at the University of Trento in Italy developed new ways to track genetic strains of microbes as they pass between individuals. That is why we try to collect as many samples as possible to obtain a global understanding of microbiome transmission in different lifestyles on the planet.

We collected more than 9,000 samples for the gut and microbiome, that is, stool and saliva samples in more than 30 different countries. We simply sequence all the DNA in the sample. The challenge here is to make sense of the sequencing data, considering that we are not looking at an individual but at a community of individuals all together. By comparing individual data across family and social networks, the researchers wanted to know if microorganisms in the microbiome could be transmitted from person to person, like a cold or a stomach virus. And what they found suggests that microbes jump much more widely than we thought between people who are in close physical proximity, such as roommates, spouses and children.

The power of our study was really that what we saw was consistent across all of these populations and different lifestyles. There really is massive transmission of members of the human microbiome directly through social interactions. So, our social activity impacts our microbiome, which in turn impacts our

biology

. So the way and the people we interact with are impacting our

biology

, our medical history. I think it deserves further study into the dynamics and the true sources and the full range of sources where these organisms come from. But this is a big step in understanding the streaming landscape. As humans evolved, our microbiomes may have evolved with us to protect our health and immunity.

But with the continued use of antibiotics and antiseptics in the modern world, we may be upsetting our body's natural microbial balance and abandoning ourselves. more susceptible to health risks. The more we study it, the more we realize that the microbiome underlies many different immune-related disorders in the body. Many of these are chronic diseases, such as cancers, autoimmune inflammatory bowel diseases and diabetes, multiple sclerosis, and many other disorders. Therefore, we usually did not understand the fundamental causes of these diseases. But as we explore them more, they are not just genetic and environmental, but they have a lot to do with these organisms that live inside our body.

We cannot fully infer causality, so we do not know if the disease occurs first or the microbiome alterations. That is why it is very important for us to understand how we acquire this bacteria and how we transmit it to other individuals. This is a human embryo. This is a mouse embryo. They both start to grow and build a body in the same way. But then something strange happens: the development of the human embryo slows down and that of the mouse accelerates. As far as we know, each step takes 2 to 3 times longer in the human embryo than in the mouse embryo.

How and when different embryonic tissues develop can drastically alter the shape of an organism. But a mystery remains. What controls this difference in time? New evidence suggests that the mysterious driver that drives development is an organelle that scientists may have dismissed as a one-trick pony. So when people think of mitochondria, traditionally, they think of the powerhouse of the cell, producing ATP to provide energy to study our functions. But they are also involved in signaling; Much more happens in mitochondria than just energy production. Discover the causal relationship between the activity of mitochondria and the timing of embryonic development.

Researchers at Harvard Medical School manipulated different regions within the mitochondria of human and mouse stem cells. and at the beginning of 2023 they published their results. Thus, we observed that mouse cells produce proteins more rapidly through the mRNA translation process than human cells. And we found that if we experimentally increased the activity of mitochondria, we could also force cells to produce proteins faster and develop faster. This finding was later echoed by a team of researchers working in Belgium in a paper they published in Science just a few weeks later, which pointed to the role of mitochondria in the development of the nervous system.

Mitochondria are important in many ways. But not only the ATP protein and the production of metabolites. And what we found is that mitochondria function as pacemakers for the speed of cell development. I think the next very important question is how mitochondrial activity regulates the gene regulatory network because the gene regulatory network is also important in regulating the timing of that development. This research could have important implications for cell therapy, which involves replacing damaged cells with healthy cells, and for cancer research. If we can find a way to accelerate the production of cells for therapies by establishing a speed of development, then that would be really important to accelerate the cell therapy revolution.

Rhythm is important to achieve a different result. That is why mitochondria are that important pacemaker and mark the diversity of our animal kingdom. So they have this function as a driving force of evolution.