September 16, 2022 – Throughout the day, your brain cells send and receive messages through electrical and chemical signals. These messages will help you flex your muscles and engage your senses—as you taste your food, feel the heat of a stove, or read the words on this page.
If we could better understand how these messages are sent and received, we would gain powerful insights into the brain-body connection and what happens at those connections are not work – as in brain diseases such as Alzheimer’s and Parkinson’s.
To do this, neuroscientists at Cedars-Sinai in Los Angeles have built computer models of individual brain cells — the most complex models they say to date. Using high-performance computing and artificial intelligence or AI, the models are created as described in the journal cell reportscapture the shape, timing, and speed of electrical signals emitted by brain cells called neurons.
The new research is part of a decades-long quest by scientists to understand the inner workings of the brain not only cognitively, but also biologically, genetically and electrically.
The most famous early researchers were Alan Lloyd Hodgkin, Andrew Fielding Huxley, and John Carew Eccles, who received the 1963 Nobel Prize in Medicine for their discoveries about nerve cell membranes.
“Today is a unique moment when detailed datasets of individual neurons are available in large quantities and for many cells,” says study author Costas Anastassiou, PhD, a research scientist in the Department of Neurosurgery at Cedars-Sinai. “The size and speed of today‘s computers allow us to explore [detailed] Mechanisms at the single cell level – for every cell.”
How do you model brain cell activity with a computer?
It turned out that the electrical impulses that neurons use to communicate can be replicated using computer code.
“We used mathematical equations to model the different voltage waveforms and time courses of these pulses,” says Anastassiou. Then they built computer models using data sets from experiments on mice.
These experiments measure certain things in the cells – like their size, shape and structure or how they react to changes. Each cell model combines all of these elements and can help show how they connect.
Computer models can reconcile two important pieces of information: cellular composition (building blocks of brain cells) and patterns observed during brain activity. With the help of the computer, connections between the data sets become clear. This could pave the way to finding out what actually changes the brain, the researchers say — a crucial step in studying disorders.
What can computers tell us about the human brain?
One of the exciting potential uses of the brain cell models would be to test all sorts of theories about brain diseases that would be difficult or impossible to create through experiments in the laboratory. In addition, the work may lead to new insights into the brain: how similar or different brain cells are, what connects or differentiates them, and what that means across a spectrum of properties.
Computers and mathematics tell stories about the brain, and Anastassiou says for him the fascination comes from the simplicity of the result and the richness of its implications.
“I’ve always been fascinated by the question of how mathematical equations represent living, computing, biological cells – particularly the brain, the epicenter of what makes us human,” he says.