The SINAPSE network includes four major MRI research centres, based at Aberdeen, Dundee, Edinburgh and Glasgow. The formation of the network has increased the imaging capability of participating sites as it has facilitated the acquisition of cutting edge imaging equipment which is compatible between imaging centres, thus enhancing the Scottish brain research community's ability to undertake multi-centre trials and research.

Facilities consist of four 1.5T MRI systems and three 3T MRI systems, four of which have fMRI capabilities. All centres also have MRI compatible EEG equipment, which will allow the concurrent collection of fMRI and EEG data.

Magnetic resonance imaging (MRI) is an ideal technique for structural imaging in the brain, with better tissue contrast than computerised tomography (CT). It can also be set up to be sensitive to the diffusion of water and thereby produce maps of white matter tracts; a technique called diffusion tensor imaging (DTI).

Our centres use an extensive range of MRI techniques to research neurological disorders including: structural; diffusion & tractography MRI; perfusion & blood flow; permeability; spectroscopy single voxel & multivoxel imaging temperature mapping; functional MRI; and EEG.

Magnetic resonance spectroscopy (MRS) complements magnetic resonance imaging (MRI) as a non-invasive means for the characterization of tissue. MRS uses MR signal spectra to determine the concentration of brain metabolites. The most widely used clinical and research application of MRS has been in the evaluation of central nervous system disorders.

In functional magnetic resonance imaging (fMRI) the contrast in signal resulting from the change in balance between oxyhaemoglobin and deoxyhaemoglobin in the brain caused by the performance of a specific task is imaged, measured and analysed. This is used to study regional brain activation and is used in many neuro-imaging research projects.

Our work in fMRI aims to harmonize protocols, tools and methods across centres in order to run more efficient multicentre studies. All centres are now equipped with the same state of the art fMRI equipment allowing audio-visual stimulation. Current work allows us to measure and define brain maps, using the same paradigms including same design and scanning parameters. The expertise in our centres is also being pooled in order to create a common toolbox to measure different image parameters using a standardised methodology. Finally, methods are being developed in order to account for scanner differences, this will improve multicentre data pooling and analysis, a key development in multicentre trials. Specific work in Edinburgh is on brain classification methods which will be extended and tested across all our centres.

Diffusion MRI (dMRI) measures the mobility of water molecules in the brain non-invasively. As water molecules tend to diffuse along, rather than across, brain white matter fibres, it is possible to map the structure and integrity of major water matter tracts in 3 dimensions (tractography). Mapping the structure of white matter tracts, effectively the brain's wiring, in-vivo allows an understanding of how different brain regions are connected and how diseases such as stroke, intracranial tumours and schizophrenia affect white matter and cause neurological dysfunction.

Key SINAPSE Brain MR Projects Include:

• Standard brain templates for ageing populations
• Artefact reduction in multi-centre MRI
• Multi-centre MRI data analysis - removing scanner specific effects
• Investigation into predictive error signal abnormality in major depression and schizophrenia
• Better clues from useful views - effects of task and image format on spatial reasoning and clinical skills for neuro-imaging
• Defining the neural basis of set shifting and reversal learning in patients with major mental illness
• Development and optimisation of MRS data acquisition in studies of treatment resistant clinical depression
• Assessment of ANATOMIST and warping to Talairach space in the accurate identification of eloquent brain areas from fMRI studies
• Cognitive function in patients newly diagnosed with type 2 diabetes

Aberdeen

Brain imaging research at the University of Aberdeen focuses on structural and functional correlates of normal and abnormal brain development, common disease states and brain ageing.

There is major strength in quantitative analysis of white matter hyperintensities and normal brain ageing on MRI. Researchers study the developing and ageing brain (with particular focus on autism and Alzheimer's disease) and the application of computational neuroimaging techniques to these processes.

There is also ongoing work in voxel-based methods for white matter abnormality segmentation, and development of tools to evaluate changes in entropy, derived from functional imaging in brain ageing and dementia.

Dundee

The Clinical Research Centre at Ninewells Hospital, Dundee, has a Siemens Trio 3T research scanner and a wide range of matrix coils provided to cover a range of clinical applications. The scanner is also fitted with a full range of facilities including fMRI and multinuclear spectroscopy. Alongside this there is MRI-compatible EEG.

Adjacent to the MRI suite is an interventional area which links to the PET/CT facility. MRI research is focussed around both cardiovascular applications and neuro studies.

A range of fMRi studies are undertaken jointly with researchers based at Ninewells hospital, the University of Dundee and the University of St Andrews.

Edinburgh

MRI research focuses on common neurological problems such as stroke, psychiatric disorders, normal ageing and dementia, Multiple Sclerosis, neuro-surgery, and prion diseases.

Researchers in Edinburgh have developed a range of MR imaging tools for studies particularly in stroke, including diffusion/perfusion and spectroscopic imaging, blood-brain barrier permeability and tractography. Considerable work has also gone into improved quantification of perfusion MRI to reduce systematic errors.

Substantial work on tractography and image processing tools for analysis of structural images in ageing is ongoing. There is significant expertise in fMRI acquisition and analysis, and in methods for combining image data from different MR sequences, timepoints and scanners, to enable longitudinal as well as multicentre studies, and improved tissue characterisation through use of multiple sequences in combination.

Glasgow

Researchers are working on improving existing arterial spin labelling sequences to aid various stroke projects in identifying metabolising tissue in the stroke 'penumbra'. Other work includes a project comparing 3T MRI of carotid plaque morphology in symptomatic patients with Doppler ultrasound, ex-vivo 7T MRI and histopathology. Researchers are also setting up an eyetracking system for an fMRI related study on macular degeneration.

There is research investigating using the software suite ANATOMIST as an alternative to referencing to Talairach space as a means of identifying areas of activation revealed by fMRI studies.