The brain is buzzing 24/7 with spontaneous, fluctuating activity
‘Resting state fMRI opens up fantastic possibilities for patients suffering from dementia or those who are in a coma, who are scarcely able to carry out any activities at all. It is also a valuable tool for research into the effects of medicines and drugs.' These were the words of neuroscientist Serge Rombouts during his inaugural lecture on Friday 1 April.
Our brains are always highly active, even when we try not to think of anything. In his lecture Professor Rombouts will show how making visible activity in the 'resting state brain' can be used in countless other domains. One example is research into antidepressants.
Rombouts, who graduated in Experimental Physics, obtained his PhD in 1999. He was the first person in the Netherlands to obtain a doctorate based on functional Magnetic Resonance Imaging (fMRI).
His research field - Methods of Cognitive Neuroimaging - mainly focuses on MRI scans. 'We not only use scans to see the structure of the brain, we also apply this method to image brain areas where oxygen usage might be increased as a result of such processes as learning, doing maths and processing language,' he explains. 'Brain cells obtain their oxygen from the red blood corpuscles. Once they have delivered their oxygen, subtle disturbances occur in a strong magnetic field. We can image this activity.'
In a classical fMRI test candidates are put in the MRI scanner and are asked to carry out particular tasks, a memory game for example, but you can also scane the brain without the person having to concentrate on anything in particualr. 'We call this resting state fMRI (RS-fMRI), even though the brain is anything but resting. It is always buzzing with spontaneous, fluctuating activity. Some brain areas seem to be just a little more active when we aren't thinking of anything, and less active as soon as we start to concentrate on something. There seems to be a pattern, a functional network of brain areas.'
Originally it was thought that there could only be one such resting state pattern, but we now know that all the networks activated by individuals when carrying out a task can be seen in resting state scanes They give us a picture of the functional architecture of the brain. 'There are always considerable individual differences with fMRI scans, and for each test candidate the picture can be different on any given day. We are able to image these networks because we analyse the scans of many, many test candidates. Only then can you detect subtle differences between men and women or between younger and older brains.'
How do these brain patterns change during development? What happens in the case of psychiatric and neurological illnesses? ‘RS-fMRI opens up fantastic possibilities for patients who are scarcely able to carry out any activities at all - dementia and coma patients, for example - and for studying the effects of medications and hallucinogenic drugs on brain activity. RS-fMRI requires hardly any preparation and has a higher success rate than task-based fMRI. I expect it will offer many new opportunities for broad clinical application.'
Rombouts works at the Psychology department of the Faculty of Social and Behavioural Sciences, and also at the Radiology department at the LUMC. He is director of the Leiden Institute for Brain and Cognition (LIBC), the brain research collaboration between the Faculties of Humanities, Medicine, Science and Social and Behavioural Sciences. The LIBC recently acquired its own MRI scanner that will officially become operational on 20 May.
Personal page Serge Rombouts
News article: Functional architecture of the brain revealed
Dossier on Brain and Cognition
(11 March 2011)