fMRI or functional magnetic resonance imaging is the measurement of activity in the brain or more precise it measures the haemodynamic response related to neural activity in the brain or spinal cord of humans or other animals. It is one of the most recently developed forms of neuroimaging.
Often results of research with fMRI have promised that we can now look inside the brain and really see what is happening in the brain during certain tasks such as memory tasks and many others.
Although brain scanner technology is often described as a "window into the brain," Logothetis, in this most recent article, makes it clear that the metaphor of transparency is inappropriate. He cites a long list of factors that complicate the interpretation of fMRI data, from the challenge of distinguishing between excitation and inhibition to the difficulty of measuring the relative activation of different brain areas. If brain scanners are like a window, then the window has some very dirty glass.
In a recent article in Nature these claims are said to be very limited by technical shortcomings of this kind of neuroimaging. The article is written by one of the experts that helped develop the fMRI technique.
Now I am not the first one to write about this nature article, but this news looked important to me so that is why I wanted to point out the other excellent descriptions of this nature article in the blogosphere:
Pure Pedantry, he also describes an excellent example of misuse of fMRI.
The Frontal Cortex