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Our default intuition when it comes to consciousness is that humans and some other animals have it, whereas plants and trees don’t. But how sure can we be that plants aren’t conscious? And what if what we take to be behavior indicating consciousness can be replicated with no conscious agent involved? Annaka Harris invites us to consider the real possibility that our intuitions about consciousness might be mere illusions.

Our intuitions have been shaped by natural selection to quickly provide life-saving information, and these evolved intuitions can still serve us in modern life. For example, we have the ability to unconsciously perceive elements in our environment in threatening situations that in turn deliver an almost instantaneous assessment of danger — such as the intuition that we shouldn’t get into an elevator with someone, even though we can’t put our finger on why.

But our guts can deceive us as well, and “false intuitions” can arise in any number of ways, especially in domains of understanding — like science and philosophy — that evolution could never have foreseen. An intuition is simply the powerful sense that something is true without having an awareness or understanding of the reasons behind this feeling — it may or may not represent something true about the world.

In a new study published by Alzheimer’s & Dementia, scientists from Rush University and Tufts University were the first to compare cognitive decline factors to vitamin D concentrations not only in the blood, but in the brain as well.

Researchers analyzed participants of the Rush Memory and Aging Project (MAP)—an ongoing longitudinal study that aims to identify risk factors for Alzheimer’s disease and other cognitive decline disorders—before and after death to see how their vitamin D levels impacted cognitive function in their later years.

Free of known dementia at the time of enrollment, all MAP participants agreed to participate in annual evaluations and organ donation when they died. In this study, the average age of participants was 92 at the time of death.

Summary: Researchers discover changes to the brain’s salience network occur when a person experiences trauma.

Source: University of Rochester.

Exposure to trauma can be life-changing—and researchers are learning more about how traumatic events may physically change our brains. But these changes are not happening because of physical injury; rather, the brain appears to rewire itself after these experiences.

Summary: A new optogenetics-based technique allows researchers to control neuron excitability.

Source: MIT

Nearly 20 years ago, scientists developed ways to stimulate or silence neurons by shining light on them. This technique, known as optogenetics, allows researchers to discover the functions of specific neurons and how they communicate with other neurons to form circuits.

One of the most enduring human mysteries is why we possess sentient awareness, a paradox known to science as the “hard problem of consciousness.”

At the physiological level, we have a good understanding that consciousness is driven by electrical impulses and chemical signals between neurons in the brain. Though precisely what regions of the brain are responsible for thoughtful experience is still a matter of debate.

However, scientists still do not understand why the same essential elements of the universe can come together to form an inanimate object like a rock or a highly complex organic structure like the human brain.

Earlier research by Dr. Li-Huei Tsai of the Massachusetts Institute of Technology and others found that APOE4 might raise Alzheimer’s risk by altering lipid metabolism in certain brain cells. But the underlying details of the process remained unclear.

To build on these findings, the team conducted a multi-pronged study that assessed gene activity of all major cell types in post-mortem human brain tissue from 32 men and women who had one, two, or no copies of the APOE4 gene. Results were published in Nature on November 24, 2022.

The researchers found that APOE4 affected gene expression across all measured cell types. The team then took a closer look at genes related to cholesterol and other lipids. Cholesterol-manufacturing genes were overly expressed, and cholesterol-transporting genes dysregulated, in brain cells called oligodendrocytes with the APOE4 gene. Oligodendrocytes are found in the brain and spinal cord. They make and maintain a fatty substance called myelin that surrounds and insulates long nerve fibers. The abnormalities were more extreme in oligodendrocytes with two copies of APOE4 rather than one.

Have you ever wondered what makes you intelligent? How are you able to see, hear, think, read, sing, solve problems, and perform any number of intelligent tasks?

Your brain learns a model of the world, and this model recreates the structure of everything you know. Everything you do and experience is based on this model. Intelligence is the ability to create this model of the world.

But how can a bunch of cells in your brain create a model of the world and everything in it? The Thousand Brains Theory provides an answer. Not only that, but it also provides a blueprint for how to build truly intelligent machines.

Visit https://numenta.com/ for more information.

The symptoms of severe obsessive-compulsive disorder, or OCD as it is more popularly known, may be reduced by half with deep brain stimulation, according to a pooled data analysis of the available data, which was recently published in the Journal of Neurology, Neurosurgery, & Psychiatry.

According to the research, two-thirds of individuals who were affected saw a significant improvement after two years.

OCD is characterized by intrusive and persistent obsessive thoughts, as well as dysfunctional and ritualized behaviors. It is estimated that up to 3% of the population is affected by it.