Hi readers!
Mike McCrae on February 9th, 2024, published in Humans (an international, peer-reviewed, open access journal on anthropology published quarterly online by MDPI) that:
Scientists have identified a unique form of cell messaging occurring in the human brain, revealing just how much we still have to learn about its mysterious inner working.
Medical researchers, please read the full article at
https://www.sciencealert.com/a-first-of-its-kind-signal-was-detected-in-the-human-brain
The discovery indicated that the human brain is a more powerful unit of computation (multiplication) than we realized.
Back in 2020, scientists from Germany and Greece reported a mechanism in the brain’s outer cortical cells that produces a novel “graded” signal on its own, and could provide individual neurons with another way to carry out their logical functions, but when:
The neurologist removed cells in the cortex of an epileptic patient‘s brain and analyzed their structure by fluorescent microscope, they found that cortical cells used not only the usual sodium but calcium ions as well to “fire.”
(Here, the word Fire is used in the sense of rapid oxidation of a material in the exothermic chemical process of combustion that release heat, light, and various reaction products).
These positively charged ions produced waves of voltage that had never been seen before and is referred to as calcium-mediated dendritic action potentials, or dCaAPs.
Human brains are often compared with computers as both use the power of an electrical voltage to carry out various operations.
In computers it is the flow of electrons through transistors while in neurons, the signal is in the form of a wave of opening and closing channels that exchange charged particles such as sodium, chloride, and potassium.
This pulse of flowing ions is called an action potential which if significant can be passed on to other nerve which in turn can block or pass on the message. This chemically mediated messaging going on at the end of nerve branches called dendrites are the core component to understand the brain because they are at the center of what determines the computational power of a single neurons and are like the traffic lights of our nervous system.
The wave of voltage passing through the neuron can be communicated in two forms. An AND message (which means if x and y (both) are triggered, the message is passed on); or an OR message (which means if x or y (which one? x or y is not yet clearly understood) is triggered, the message is passed on). This happens in the outer layer of cortex while the cerebral cortex which is dense and wrinkled outer section of the human central nervous system is not in the picture.
Hence leaving aside this, the deeper second and third, more thick layers that are packed with branches involved in carrying out functions associated with sensation, thought, and motor control caught the attention of the scientists, and it was the tissues from these layers that the researchers thoroughly analyzed by hooking up these cells to a device called somato-dendritic patch clamp to send active potentials up and down each neuron for recording their signals when they observe the dendritic action potentials for the first time.
To ensure that the discovery was not unique in people with epilepsy, the results were double checked with the sample taken from brain tumors and the experiment was also carried out on rats however, the signal received from human brain cell sample were very different. Also, when cells were closed with sodium channel blocker, the signals could still be found but when blocked by calcium, all signals went off.
The action-potential mediated by calcium was interesting but modelling the way this sensitive new kind of signal worked in the cortex was surprising because in the logical AND / OR-type functions, the individual neurons could only act as exclusive OR (XOR) intersections to permit a signal when another signal is graded in a particular fashion, thus for XOR operations, it is imperative to have a network solution (A network solution refers to the services provided by a network consulting or service provider company that helps organizations design, implement, and manage their network infrastructure including network planning, design, security, monitoring, maintenance, and support) but, how dCaAPs behave across a network solution remains to be seen.
Take home message!
Technology is being used as an inspiration on how to develop better hardware to know our own individual cells that will open new ways to network transistors. How will this new logic tool unfold into a single nerve cell that translates into higher functions? And how it will be used to treat epilepsy? is a question to be answered by medical researchers. But the pace at which technology is developing the future seems to be bright and in safe hand.
See you next week. Take care, Bye.
