Karl Friston shows that different global brain theories all describe principles by which the brain optimizes value and surprise. He discusses how these brain theories fit into the free-energy framework, suggesting that this framework might provide a unified account of brain function.
Can you recognize someone you haven’t seen in years, but forget what you had for breakfast yesterday? Our brains constantly rearrange their circuitry to remember familiar faces or learn new skills, but the molecular basis of this process isn’t well understood. Today, scientists report that sulfate groups on complex sugar molecules called glycosaminoglycans (GAGs) affect “plasticity” in the brains of mice. Determining how GAGs function could help us understand how memory and learning work in humans, and provide ways to repair neural connectivity after injuries.
The researchers will present their results today at the fall meeting of the American Chemical Society (ACS).
The sugars that sweeten fruits, candies or cakes are actually just a few simple varieties of the many types of sugars that exist. When strung together, they can make a wide array of complex sugars. GAGs are formed by then attaching other chemical structures, including sulfate groups.
Exactly how, and how much, the unconscious processing of information influences our behavior has always been one of the most controversial questions in psychology. In the early 20th century, Sigmund Freud popularized the idea that our behaviors are driven by thoughts, feelings, and memories hidden deep within the unconscious mind — an idea that became hugely popular, but that was eventually dismissed as unscientific.
Modern neuroscience tells us that we are completely unaware of most brain activity, but that unconscious processing does indeed influence behavior; nevertheless, certain effects, such as unconscious semantic “priming,” have been called into question, leading some to conclude that the extent of unconscious processing is limited.
A recent brain scanning study now shows that unconsciously processed visual information is distributed to a wider network of brain regions involved in higher-order cognitive tasks. The results contribute to the debate over the extent to which unconscious information processing influence the brain and behavior and led the authors of the study to revise one of the leading theories of consciousness.
A study that peered into live mouse brains suggests for nearly 70 years we’ve been targeting the wrong neurons in our design of antipsychotic drugs.
Untangling the vast web of brain cells and determining how drugs work upon them is a tough task. Using a miniature microscope and fluorescent tags, a team of researchers led by Northwestern University neuroscientist Seongsik Yun discovered that effective antipsychotic drugs cling to a different type of brain cell than scientists originally thought.
Just like research suggesting depression might not be a chemical imbalance in serotonin levels, our understanding of schizophrenia treatments may need a rethink if widely-used antipsychotics are targeting different neurons than expected.
Psychedelics are known for inducing altered states of consciousness in humans by fundamentally changing our normal pattern of sensory perception, thought and emotion. Research into the therapeutic potential of psychedelics has increased significantly in the last decade.
While this research is important, I have always been more intrigued by the idea that psychedelics can be used as a tool to study the neural basis of human consciousness in laboratory animals. We ultimately share the same basic neural hardware with other mammals, and possibly some basic aspects of consciousness, too. So by examining what happens in the brain when there’s a psychedelically induced change in conscious experience, we can perhaps glean insights into what consciousness is in the first place.
We still don’t know a lot about how the networks of cells in the brain enable conscious experience. The dominating view is that consciousness somehow emerges as a collective phenomenon when the dispersed information processing of individual neurons (brain cells) is integrated as the cells interact.
A team of scientists took a bunch of macaque monkeys, made them into alcoholics, and then successfully weaned them off the sauce after injecting their brains with a special gene — an experiment, detailed in a new paper published in Nature Medicine, that could potentially provide a compelling new treatment for addiction.
“Drinking went down to almost zero,” Oregon Health and Science University professor and co-author Kathleen Grant told The Guardian. “For months on end, these animals would choose to drink water and just avoid drinking alcohol altogether.”
The researchers set out with the premise that continued alcohol use causes changes to neurons and hampers the dopamine “reward circuitry” in the brain.
Since this book is about what I consider intellectual subject matter, I think it’s relevant to keep brains in top shape and thought it would be important to share this. You probably know about this sort of thing but I didn’t know the specific nutrients needed and what was lacking in people with Alzheimer’s. Best wishes.
Alzheimer’s disease is a progressive neurodegenerative disease estimated to affect 6 million Americans and 33 million people worldwide. Large numbers of those affected have not yet been diagnosed.
A new study published in the Journal of Alzheimer’s Disease by a Virginia Tech Carilion School of Medicine faculty member shows that brain levels of dietary lutein, zeaxanthin, lycopene, and vitamin E in those with Alzheimer’s disease are half those in normal brains. Higher dietary levels of lutein and zeaxanthin have been strongly linked to better cognitive functions and lower risk for dementia or Alzheimer’s disease.
The John Templeton Foundation recently invited biologist Michael Levin to speak to a small group about the presence of agency and cognition in the most fundamental forms of life, even at the levels of cells and tissues. In the recorded video, Dr. Levin, who directs a developmental biology lab at Tufts University, discusses with Philip Ball, a science writer and author of the newly published Book of Minds: How to Understand Ourselves and Other Beings.
Founded in 1987, the John Templeton Foundation supports research and dialogue on the deepest and most perplexing questions facing humankind. The Foundation funds work on subjects ranging from black holes and evolution to creativity, forgiveness, and free will. It also encourages civil, informed dialogue among scientists, philosophers, theologians, and the public at large.
Continue reading “Can Cells Think? The Magic of Developmental Biology” »
A research team co-led by City University of Hong Kong (CityU) and The University of Hong Kong (HKU) has recently made a significant advancement in spinal cord injury treatment by using genetically-modified human neural stem cells (hNSCs).
They found that specifically modulating a gene expression to a certain level in hNSCs can effectively promote the reconstruction of damaged neural circuits and restore locomotor functions, offering great potential for new therapeutic opportunities for patients with spinal cord injury. The findings were published in the journal Advanced Science under the title “Transplanting Human Neural Stem Cells with ≈50% Reduction of SOX9 Gene Dosage Promotes Tissue Repair and Functional Recovery from Severe Spinal Cord Injury.”
Traumatic spinal cord injury is a devastating condition that commonly results from accidents such as falls, car crashes or sport-related injuries.
