Many people have questioned the validity of inferences drawn from fMRI studies and this very timely article, published here today helps shed some light on the topic. The article states that:
A new study has raised new questions about how MRI scanners work in the quest to understand the brain. The research, led by Professor Brian Trecox and a team of international researchers, used a brand new technique to assess fluctuations in the performance of brain scanners as they were being used during a series of basic experiments. The results are due to appear in the Journal of Knowledge in Neuroscience: Generallater today.
“Most people think that we know a lot about how MRI scanners actually work. The truth is, we don’t,” says Trecox. “We’ve even been misleading the public about the name – we made up functional Magnetic Resonance Imaging in 1983 because it sounded scientific and technical. fMRI really stands for flashy, Magically Rendered Images. So we thought: why not put an MRI scanner in an MRI scanner, and figure out what’s going on inside?” To do this, Trecox and his team built a giant imaging machine – thought to be the world’s largest – using funds from a Kickstarter campaign and a local bake sale. They then took a series of scans of standard-sized MRI scanners while they were repeatedly switched on and off, in one of the largest and most robust neuroscience studies of its type.
“We tested six different MRI scanners,” says Eric Salmon, a PhD student involved in the project. “We found activation in an area called insular cortex in four of the six machines when they were switched on,” he added. In humans, the insular cortex has previously been implicated in a wide range of functions, including consciousness and self-awareness. According to Trecox and his team, activation in this area has never been found in imaging machines before. While Salmon acknowledged that the results should be treated with caution – research assistants were found asleep in at least two of the machines – the results nevertheless provide a potentially huge step in our understanding of the tools we use to research the brain.
However, some researchers are skeptical of the findings. Professor Stephen Magenter, Professor of Image Processing at Yate University, UK, is a vocal critic of the statistical analyses that Trecox used. “They just used felt tip pens to highlight and extend the areas they were interested in,” he alleges, adding that he would never colour outside the lines. In response to these claims, Salmon says that this study was one of the most advanced of its kind. “All of our analyses were digital,” he notes. “We used MS paint wherever possible.”
The findings raise interesting questions about how fMRI techniques should be used from now on. “If there’s a possibility that MRI machines are showing some sort of rudimentary self-awareness, then we really need to explore this further,” says Trecox. He adds: “One way to do this is to look at what’s happening in our giant scanner, and for that, we’re going to need a bigger machine.”
And for those of you still uncertain about this article you may want to check it’s publication date 🙂