香港六合彩

Dr Joost Haarsma, a Research Fellow in the Centre鈥檚听, is using the scanner to explore communication between different layers of the cortex 鈥� the outermost layer of the brain, responsible for many higher-order brain functions such as sensation and perception.

鈥淵our grey matter and your cortex is about two and a half millimetres thick. And that鈥檚 divided into roughly six layers,鈥� he explains. 鈥淚n order to look at those individual layers, and how they talk to each other, you need an even smaller resolution. This is what we get with 7T.鈥�

The 7T scanner stands out because of the strength of its magnetic field. This dramatically increases the resolution of scanning images and reveals more intricate details about the structure of the brain.

Dr Haarsma鈥檚 research is primarily concerned with how the cortex allows us to see things. Specifically, things that aren鈥檛 actually there.

鈥淭he idea is that the brain has an expectation and these expectations are the brain鈥檚 best guess at what鈥檚 going to happen next. Now these guesses are often not correct, and when they鈥檙e not correct, they need to be corrected.

鈥淚f there is a new sensory input, which doesn鈥檛 match the expectation, then certain signals in the brain, called 鈥榩rediction error signals鈥�, will correct that expectation. And then hopefully, your best guess is going to be better next time and your perception is correct.鈥�

It is particularly the deeper layers of the cortex that become activated by expectations. If hallucinations are a result of stronger expectations, then researchers should be able to observe increased activity in the deep cortex when people are hallucinating.

The powerful 7T scanner is needed to distinguish between distorted expectations and another possible culprit for hallucinations: the visual input system.

鈥淵ou can only tease those things apart when you have a high enough resolution to look at the different layers.鈥�

听Dr Peter Kok, Principal Investigator of the听, is also pleased with the results so far: 鈥淲e鈥檝e compared the kind of data we鈥檝e been getting from these different scanners and as it stands it鈥檚 looking promising.鈥�

鈥淲hat鈥檚 also really crucial for that is the Physics team we have at the [Centre],鈥� he said, 鈥淏ecause this magnet doesn鈥檛 do anything on its own. It all depends on programming it in the right way so that you get the right type of data out of it. And that鈥檚 what the Physics team is really good at. So we鈥檝e been working with the Physics team and optimising the data collection.鈥�

Joining forces with other groups across the Centre and the wider 香港六合彩 community has also been one of the highlights for Physics team leader Professor Callaghan.

鈥淲hat I absolutely love about it is the attitude people have. The people who are most active in the area are just really excellent to collaborate with. They want to do new things and they鈥檙e always coming to us with new challenges. I would say that鈥檚 invigorating.

The scanner was funded by the Leopold Muller fund, Brain Research UK, Wellcome, and 香港六合彩鈥檚 Capital Equipment Fund.

Links

• 香港六合彩 Queen Square Institute of Neurology 听