Scientists rarely get straight to the point. An ode to the unexpected discoveries. Today: how Tomas Knapen discovered a new brain layout in his spare time.
“Nearly died from a jellyfish sting, it happened to me in Thailand in January 2020. I quickly flew back to the Netherlands, for a while I couldn’t work. My way of taking it easy was to start a new project.
‘For my research at the time, we had test subjects look at images in an MRI scanner: flickering bars or dots, for example. We measured which parts of the brain become active. Such studies are the standard in neurology, because then you can adjust one variable at a time – for example, how many bars you see or where on the screen they appear – and measure the effect. However, they are not a good representation of reality: test subjects are not allowed to look around and the images are dull and silent.
‘Researchers found a solution for this in a large American project: 180 test subjects watched a series of video clips for an hour. They did this one by one in a powerful MRI scanner, which enabled the researchers to precisely measure brain activity. Compared to our study, with no more than ten or twenty test subjects, this yielded so much more data of very high quality.
‘This dataset was just hard to find. The story goes that funding for the study expired and the researchers never published the final result. The data was online on an obscure website and thanks to American colleagues I knew about its existence.
‘I never had time to look at that dataset: compared to my research with simple images, the analysis was a lot more complex. So then I was stuck at home because of that jellyfish bite: teaching and meetings didn’t work, but I couldn’t resist doing research. After my recovery, the Netherlands was also in the first lockdown, which meant that experiments with an MRI scanner were canceled. Now I could do that difficult analysis.
‘We knew beforehand that parts of the brain are visually structured. Your eyes capture light and project it onto your retina at the back of your eyeball. This passes the information on to the brain. If something appears on the right side of your retina, it will also end up on the right side of your brain. Compare it to a map: it shows Amsterdam north of Rotterdam, just like in real life. Still other areas of the brain classify that information into categories. They recognize in a living being, for example, whether it is a human being or an animal.
‘To my disbelief, many of those category areas turned out to be visually oriented at the same time. This also applies to the hippocampus, the part of the brain that plays an important role in memory: images that fall on the right side of your retina also appear on the right side of your hippocampus. Quite logical actually: memories go hand in hand with images. To watch a movie starring Tom Cruise, match his face to the part he’s playing.
‘The research is a small building block towards the theory that everything in the brain with visual images is closely intertwined. This leads to interesting follow-up questions. In Alzheimer’s, which we know as a memory disorder, for example, the hippocampus is damaged. What if vision is also affected? And how does the brain work in people with autism, who can quickly become overstimulated? Without that jellyfish bite I would never have been able to ask these questions.’
Tomas Knapen is a cognitive neuroscientist at VU University Amsterdam and principal investigator at the Spinoza Center for Neuroimaging and the Netherlands Institute for Neuroscience. He studies how seeing works in the brain.