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Adult Brains More Flexible Than Previously Thought
stemceller passed us a link to the official site for Johns Hopkins, which is reporting on some research into cognition. Generally, doctors have understood our best learning to be done at a young age, when the brain has a 'robust flexibility'. As we get older, our brain cells become 'hard-wired' along certain paths and don't move much - if at all. Or, at least, that was the understanding. Research headed by the hospital's Dr. Linden has taken advantage of 'two-photon microscopy', a new technique, to get a new picture inside a mouse's head. "They examined neurons that extend fibers (called axons) to send signals to a brain region called the cerebellum, which helps coordinate movements and sensory information. Like a growing tree, these axons have a primary trunk that runs upward and several smaller branches that sprout out to the sides. But while the main trunk was firmly connected to other target neurons in the cerebellum, stationary as adult axons are generally thought to be, 'the side branches swayed like kite tails in the wind,' says Linden. Over the course of a few hours, individual side branches would elongate, retract and morph in a highly dynamic fashion. These side branches also failed to make conventional connections, or synapses, with adjacent neurons. Furthermore, when a drug was given that produced strong electrical currents in the axons, the motion of the side branches stalled.'"
They just normally prefer not to do so.
I had to fight them for a long time to use it, but now even my parents (in their 60s) suffer from internet withdrawal if they go without for a few days.
There's a branch of neural net studies that focuses on a technique called entropic topography. Essentially, it involves random evolution of just the fringes of a digital neural net. That is, much as this John-Hopkins study has found, a rigid core is kept. It is only the neural subnets branching off that undergo synthesis and morphing.
While there are various deterministic algorithms that are used to evolve neural nets, it's only recently that we've begun seeing randomness used. This has an added benefit of bringing in unexpected mutations, which really don't happen with the deterministic algorithms.
Some advances from the study of Lei topographies have also lead to breakthroughs recently, where some of the more complex, yet deterministic, algorithms have had entropic terms introduced in order to bring in an element of randomness. These neural nets are probably the closest to the human brain, as they introduce the random mutation that is so prevalent within the human species, while also following the constraints of this new-found core neural path.
I hate this view that some how results of tests on animals don't apply to humans at all. It's simply not true, almost every major medical advance has been tested or researched on animals like mice first. the simple fact is mammals bodies all work in very similar ways.
Having worked in a lab (disclaimer: not as a scientist) I learned that there are loads and loads of promising treatments for cancer and such that work great in mice, and never translate beyond. Even a casual glance at immunology from a layman's perspective reveals your statement to be utter bullshit; there are many, many diseases and afflictions that are species specific, sometimes highly so.
Anyway...it is entirely plausible that this ability to re-purpose brain cells is a plus for mice in survival/adaptation, where they have very little brain capacity at their disposal. We have loads at our disposal, and tend to build a lot of generally useful knowledge..ie, we build tools, literally or figuratively, and apply those 'real' tools or knowledge/skill 'tools'. Mice do not do either. We're more "general purpose", so maybe we don't *need* the ability to re-learn, since our learned skills are so broadly applicable in a survival sense.
Please help metamoderate.
Let me get this straight. An adult may be just as capable of learning something new as someone younger. But they aren't as capable of re-considering things they already know. I.E. they have a harder time changing their already established brain structure but forming new structures isn't a problem. Anyone?
That is actually an important observation that often goes unexplained. The fact is, mice are genetically very close to humans, but they reproduce quickly, are cheap, and their genetics and physiology are very well understood. That makes them a great animal to experiment on.
At the cellular level, most mammals are very, very similar to each other. In fact, we know so little about neurology in the first place, any understanding we can draw from mice helps us understand the basics of the vertebrate nervous system.
Most importantly, we cannot breed and sacrifice humans for the purpose of experimentation. The best we can do is use animals and hope that they are close enough (usually they are, by the way).
- Demosthenes
cynicsreport.com
As there seems to be some neuroscientists and neurologists on /., I'd like to ask the following question as its a somewhat related topic.
There is a man in his early 20's who recently recited pi to some 200,000 digits perfectly at Oxford university. He says he can visualize numbers in his head and is able to (as Oxford researchers found) do division to a precision of 20 or more decimal places in his head (there are some techniques to do this too I'm sure).
The point is he's said that his ability to visualize numbers occurred after having an epileptic seizure. After being diagnosed and (presumably treated with medication), his brain still functions in the same way that he's able to visualize the numbers.
Prior to being diagnosed with my seizure condition, I remember having epileptic episodes (the disorientation and spatial loss) where I was able to do more complex math and deeper thoughts that I ever thought I was able to do. As a senior in HS, I was able to complete math and science homework for sometime in a fraction of the time it would usually take. E.g. 25 minutes total vs 1-2 hours total each night. I haven't been able to unlock this thought process since.
Any thoughts or ideas on what caused this? And -without- any risk to myself, is there any current research on unlocking this potential?