Brain measured at high resolution for the first time – New Scientist

To determine the activity of human brains, we mainly look at scans taken from the outside. These methods don’t show as many details as you would like. researcher Iris Green I looked at people’s brains via implants, and thus gained more insight into our vision.

How do you measure brain activity in the brains of living people?

Scanners that measure from the outside, such as an fMRI or an EEG, are usually used. In fact, we measured inside people’s brains with electrodes. This has never been done in such high resolution before. Of course you can’t just do that: for that you have to open the skull and the brain. In this case, we are talking about people who already have electrodes in their brains, that is, patients with epilepsy. They were given these implants for clinical purposes. We were able to use it for our research.

What did you look at?

We studied how the brain functions in the part responsible for visual perception. How do we see images and how do we process them? Usually it is not only difficult to get into the brain, but also to measure in that specific area of ​​the brain. Our brain activity originates from the neurons in our brain, and nervous cells, which communicate with each other: by shooting they send signals. The step from what we see in the outside world to the firing patterns of neurons is not yet entirely clear. We have tried to define it.

So how can we see things that have never been studied?

“Yes, a lot of research is being done on visual perception. And you can actually look inside the brain of lab animals, but never in humans. Based on previous animal experiments, we created mathematical models that indicate how neurons respond to visual input. But we didn’t know what If it works the same way in the human brain.Through this research, we show that the visual part of the brain has a single mechanism that can be captured in a simple mathematical model.

What can you do with this model?

Personally, I want to see how we can use this knowledge to improve computer algorithms. would Artificial intelligence – Artificial intelligence – can help to “see” better. Much of today’s artificial intelligence is actually inspired by the knowledge we have about the brain. These kinds of principles are built into what are called neural networks, which have already led to, for example, facial recognition on your phone.

But AI can still learn things from the human process. So far it can only perform very specific tasks that belong to certain inputs. If this entry changes, the system must be completely retrained. She cannot yet adequately adapt to the changing images. Our mathematical model shows how the human brain does this.

Could research also help people see better?

My research is not directly related to this, but other researchers are working on implants for people who are blind because there is a problem with the connection between their eyes and their brain. Then the brain is actually fine, but the information from the eyes can’t get there.

In this case, all you have to do is place a device where the visual information comes naturally and stimulate the neurons there. A number of patients are already experimenting with these implants. This is really groundbreaking work. Our research may help with that.