Turner, Professor Bob

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http://www.fil.ion.ucl.ac.uk/Turner/

My primary research consists of development of magnetic resonance methods for greater scientific understanding of the human brain.

In the initial stages (1986-88), this involved precise design of MRI gradient coils, based on the Maxwell Equations, to allow ultra-fast echo-planar imaging (EPI), capable of recording the rapid changes in blood flow associated with brain function. The design principles I established are now universally employed by MRI scanner manufacturers.

Using a home-built coil, I demonstrated (1992) that EPI could be used in humans to study brain function (fMRI) at the high field strength of 4 Tesla, and introduced the technique at the USA's National Institutes of Health.

Subsequently, as a founder Principal at the Functional Imaging Laboratory in London, I set up functional MRI methodology, forming the Physics Group for this purpose, now headed by Dr Ralf Deichmann. This Group also has responsibility for the cognitive interface between experimenter and subject that allows well-designed and properly controlled functional brain mapping experiments to be performed.

Water mobility in the brain can be measured with MRI (diffusion-weighted imaging, DWI), but to avoid artifacts due to head motion it is necessary to use EPI. I was the first researcher (1990) to demonstrate this technique, which is now used widely to map brain abnormalities and to track the axonal bundles of nerve fibres connecting brain regions. I continue to investigate potential improvements in MRI methods for fibre tracking.

MRI has the capability to detect subtle differences in brain tissue. My primary goal now is to useMRI to provide excellent anatomical depiction of the human brain. With the FIL Physics Group I improved existing techniques for this purpose.

Moving in 2003 to the adjacent High Field Laboratory headed by Professor Roger Ordidge, I continue to refine MRI anatomical techniques to a point where intracortical details can be visualized. Combining grey matter anatomy, axonal fibre connectivity, and functional brain imaging, it is becoming possible to map the functional organization of individual's brains in fine detail, and to correlate this with underlying anatomy. Currently I am pursuing this research using the 4 T MRI scanner at the Research Center in Jülich, Germany, with Professor Jon Shah and Professor Karl Zilles.

Secondary research areas are: the anatomy and logistics of cortical surface vasculature; investigation by fMRI of brain systems involved in production and perception of music; and integration of the insights of social anthropology with models of brain function.