Recently we have looked at the impressive progression in the ability of fMRI scanners to record brain activity in ‘real time’ but are we over interpreting these results? Over the last decade-or-two more-and-more researchers have been turning to fMRI scanners to open the ‘black box’ which is the brain. These scanners measure brain activity by measuring the amount of oxygen in the different parts of specific cortical or sub-cortical areas (this is a very simplistic view of the technology).
However, there is a storm brewing about the validity of these scanners and questions being raised about the short-sightedness of using fMRI scanners to ‘pin-point’ specific areas within the brain when localising functions; asking the question are we oversimplifying the location of functions in the brain by doing this?
[fMRI] scanners, they say, excel at measuring certain types of brain activity, but are also effectively blind when it comes to the detection of more subtle aspects of cognition. As a result, the pictures that seem so precise are often deeply skewed snapshots of mental activity. [Boston Globe via Frontal Cortex]
Could we then be basing some of the conclusions from studies that utilize fMRI (such as Maguire) on distorted data and can we really be confident in localising complex functions within the brain to just one location?
These critics stress the interconnectivity of the brain, noting that virtually every thought and feeling emerges from the crosstalk of different areas spread across the cortex. If fMRI is a window into the soul, these scientists say, then the glass is very, very dirty!
I think it’s important to note that fMRI is one of (if not the) best imaging technique that we have at the moment and the data that it provides is invaluable to both the medical and psychological research teams that utilize it. We just need to be aware of it’s limitations, well, actually the limitations of any brain scanning technique, in trying to pinpoint specific functions in our magnificently complex brain.