September 16, 2022 – Throughout the day, your brain cells send and receive messages through electrical and chemical signals. These messages help you do things like move your muscles and use your senses – when you taste your food, feel the heat from 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 shed light on what happens when these connections are not work – as with brain diseases such as Alzheimer’s disease and Parkinson’s disease.
To that end, neuroscientists at Cedars-Sinai in Los Angeles built computer models of individual brain cells — the most complex models to date, they say. Using high performance computing and artificial intelligence, or AI, models, as described in the magazine Cell reportscapture the shape, timing and speed of electrical signals that brain cells called neurons fire.
The new research is part of a decades-long quest among scientists to understand the inner workings of the brain, not just cognitively, but biologically, genetically and electrically.
The most famous early researchers were Alan Lloyd Hodgkin, Andrew Fielding Huxley and John Carew Eccles, who won the Nobel Prize in Medicine in 1963 for their discoveries on nerve cell membranes.
“Today is a unique time when detailed single neuron datasets are available in large quantities and for many cells,” says study author Costas Anastassiou, PhD, a researcher in the Department of Neurosurgery at Cedars-Sinai. “Today’s size and speed‘s computers allow us to explore [detailed] mechanisms at the level of a single cell – for each cell.
How do you model brain cell activity using a computer?
It turns out that the electrical impulses that neurons use to communicate can be reproduced using computer code.
“We reproduced the voltage waveforms and distinct time trajectories of these pulses using mathematical equations,” Anastassiou explains. Next, they built computer models using datasets from mouse experiments.
These experiments measure certain things in cells – like their size, shape and structure, or how they respond to changes. Each cell model combines all of these elements and can help reveal how they connect.
Computer models can reconcile two essential pieces of information: cellular composition (the building blocks of brain cells) and the patterns observed during brain activity. With the help of the computer, the links between data sets become clear. This could help pave the way to discovering what actually makes the brain change, the researchers say – a crucial step in examining the disorders.
What can computers tell us about the human brain?
One of the exciting potential uses of brain cell models would be to test all sorts of theories about brain disorders that would be difficult or impossible to create through laboratory experiments. Beyond that, the work may lead to new insights into the brain: how similar or different brain cells are, what connects or makes them different, and what that means across a range of properties.
Computers and mathematics tell stories about the brain, and Anastassiou says for him that the fascination comes from the simplicity of the result and the richness of their impact.
“I’ve always been fascinated by the question of how mathematical equations represent living, computational and biological cells – especially for the brain, the epicenter of what makes us human,” he says.