Everyone wants to feel special and unique.
Lucky for all of us, a new study has shown that our brains do indeed have unique signatures—and that’s not just good news for our egos. Soon, doctors could use these electrical signatures to figure out whether the motor circuits of a paralyzed person’s brain still work.
When researchers scan the brains of people carrying out tasks, the brain waves they see show lots of differences among subjects. But it’s been tricky figuring out whether this is due to the individuals using slightly different strategies to accomplish the same task or if people’s brain circuits actually had unique connections.
Now, a team of neuroscientists found a way to show it’s the brains’ own specific structure that causes the unique brain waves. They used the brain’s activity at rest—its signature—to predict what it will look like while gambling, trying to access a memory, reading, and doing other tasks.
The researchers used a brain scanning technique called functional magnetic resonance imaging, or fMRI, first used in the 1990s. In the early days of the technique, the developers saw that even before subjects did any cognitive exercises, the fMRI scans showed a constant low level of brain waves. Some researchers thought it was just static. But it turns out the activity collected when the brain is at rest is full of meaning.
Here’s Simon Makin, reporting for Scientific American:
This type of scan, it turns out, reveals a lot about a particular brain. It analyzes the commonplace slow fluctuations of neural signaling, which form networks of brain cells that fluctuate in synchrony—and these networks often resemble those the brain engages when it is actively doing something. “We’ve known for a while that the brain networks we pull out of resting-state data look similar to the maps we get from task-induced activity,” says neuroscience doctoral student Emily Finn of Yale University. Finn and her colleagues published a study last October showing that brain networks contain enough information to identify individuals with up to 99 percent accuracy. “This study takes things a step further,” Finn says.
The new study analyzed how the resting brain waves were related to the working brainwaves. They were able to show that there were clear connections between the different states. Next, they used the brain waves from the resting brains to predict what the fMRIs would look like when the subjects did some brain-work.
What they found was exciting. For a task like reading, the predicted reading brain waves were more like the real ones for a subject than the reading brain waves recorded from other subjects.
This means that neuroscientists now have a way of figuring out whether parts of a person’s brain are functioning even if the person can’t perform common tasks used to study brain function. This is especially important for newborns, paralyzed people, and patients in comas. If doctors can figure out what regions of the brain are not working as they should, they can better treat the patients.