First-of-Its-Kind Signal Detected in The Human Brain
Scientists have recently identified a unique form of cell messaging occurring in the human brain that’s not been seen before. Excitingly, the discovery hints that our brains might be even more powerful units of computation than we realized.
Back in 2020, researchers from institutes in Germany and Greece reported a mechanism in the brain’s outer cortical cells that produces a novel ‘graded’ signal all on its own, one that could provide individual neurons with another way to carry out their logical functions.
By measuring the electrical activity in sections of tissue removed during surgery on epileptic patients and analyzing their structure using fluorescent microscopy, the neurologists found individual cells in the cortex used not just the usual sodium ions to ‘fire’, but calcium as well.
This combination of positively charged ions kicked off waves of voltage that had never been seen before referred to as calcium-mediated dendritic action potentials, or dCaAPs.
Brains – especially those of the human variety – are often compared to computers. The analogy has its limits, but on some levels, they perform tasks in similar ways. Both use the power of an electrical voltage to carry out various operations. In computers, it’s in the form of a rather simple flow of electrons through intersections called transistors.
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. Instead of transistors, neurons manage these messages chemically at the end of branches called dendrites. Dendrites are the traffic lights of our nervous system. If an action potential is significant enough, it can be passed on to other nerves, which can block or pass on the message.
