Morphology Guided fMRI

As the potentials for treating neurological disorders have increased tremendously the last decades, there is also a growing need for safe, reliable and cost-effective diagnostic tools. fMRI is valuable both for an improved description of normal brain function and for assessment of patients with neurological disorders. The core theoretical idea in the project is that by including/developing tools for reconstruction of the brains cortical surface new and highly significant local spatial priors can be included in the fMRI data analysis and in this way significantly improve detection performance.

• Staff:

Hans Knutsson , Professor		Project Manager/Supervisor		LiU/IMT
Mats Andersson , Research Eng.		Theoretic developement		LiU/IMT
Anders Eklund , PhD Student		Theoretic developement		LiU/IMT

• Former Staff:

Birgitta Söderfeldt , Professor		Supervisor		LiU/INR
Magnus Borga , Docent		Co-supervisor		LiU/IMT
Joakim Rydell , PhD student		Theoretic developement		LiU/IMT
Björn Svensson , PhD student		Theoretic developement		LiU/IMT
Andreas Wrangsjö , PhD student		Theoretic developement		LiU/IMT

• Project Description:

fMRI research directions

As the potentials for treating neurological disorders have increased tremendously the last decades,
there is also a growing need for safe, reliable and cost-effective diagnostic tools. fMRI is valuable both
for an improved description of normal brain function and for assessment of patients with neurological
disorders. Below follows an outline of the planned activities in fMRI research. Both theoretical
research direction and medical target areas are suggested.

Theoretical development

The detection of active brain areas is a challenging problem due to high noise levels and artifacts
present in the data. A fundamental theoretical tool in the research will continue to be Canonical
Correlation Analysis (CCA). Currently spatial basis functions are used that implicitly perform an
adaptive spatial filtering of the fMRI images significantly improving detection performance. Further
improvement has been possible by introducing a constrained version of CCA incorporating prior
information about spatio-temporal response features.
The present project aims at going even further in this direction. By including/developing tools for
reconstruction of the brains cortical surface new and highly significant local spatial priors can be
included in the fMRI data analysis. The local orientation and thickness of the gray matter can
hopefully be reasonably well estimated and used to define a local coordinate system. In this way it
will be possible orient the spatial filters in an optimal way and avoid mixing adjacent voxels that are
in fact far apart on the cortical surface. The project is theoretically challenging but the rewards if
successful are obvious.

Stroke

For persons affected by stroke neuroimaging is an important part of the assessment. As new treatments
that may reverse cerebral ischemia have been developed, the role of neuroimaging has changed from
just anatomic depiction of early infarction to identification. fMRI is also as a valuable method to
evaluate the rehabilitation and plasticity after cerebrovascular disorders. The overall goals are early
detection, intervention, and individualized treatment.

Sub projects:

1.Construction of simple language paradigms with the purpose to have a paradigm bank usable for
aphasia and other language disturbed patients.

2.Studies on stoke patients with aphasia to follow the plasticity and reorganization during the reha-
bilitation

Epilepsy

Epilepsy is a common disorder, affecting about 0,7 population and the fits often start in childhood
and can lead to life-long handicaps if not successfully treated. New imaging techniques have added
important information about the epileptogenic lesions. Also minor structural changes causing epilepsy
can be detected at MRI and the combination of different MRI approaches including fMRI. Further,
reorganization of the brain may occur as a consequence of the epileptogenic activity and some drugs
used for treatment of epilepsy affects language and/or memory.


Sub projects:

1.fMRI as a technique to determinate which hemisphere is language dominant for epilepsy surgery patients.

2. Effect on language function for epilepsy patients treated with topiratmate
                                                


Other possible medical application areas:

1.Emotional memories - normal subjects

2.Memory function in patients with pain syndromes etc Vision

3. Quality assessment of fMRI methods through stabilized retinal stimulation