Introduction

The international workshop Brain Connectivity 2005 will be held in Boca Raton, Florida, in April 15th-16th, 2005 and brings together scientists from various disciplines including neuroscience, medicine, brain imaging, physics and mathematics. The core question raised at this conference is how does the brain’s connectivity influence its function and information processing? We will discuss principles of spatiotemporal pattern formation, measures of connectivity and dynamics, as well as clinical aspects of anatomical and functional connectivity.

This workshop has been held in Düsseldorf, Germany, in Cambridge, England, and in Havana, Cuba, in previous years.   Information on some of these meetings may be found at www.neuroinf.org under the meetings link. Each speaker will give a 50min presentation and focus on the key concepts, sometimes provocatively, to stimulate discussions. This format has proven to be successful in the last meetings and ensured a maximum of interactions. There will be no additional poster sessions.

Structure and Function

Obviously, the brain’s connectivity influences its information processing, but so far we do not have a real understanding of the relationship between connectivity and the resulting neural dynamics. Clinically established methods such as MRI (Magnetic Resonance Imaging) image routinely the anatomy and structure of the brain, but do not detect any functional aspects of the brain’s processes. On the other hand, not yet clinically used brain imaging techniques have recently emerged which can detect brain activations non-invasively. For instance, functional MRI (fMRI) identifies active regions and networks in the brain during functionally relevant tasks such as moving a finger or memorizing numbers. Other brain imaging techniques that identify functionally relevant brain processes include positron emission tomography (PET), electroencephalography (EEG) and magnetoencephalograpghy (MEG). The merging of such structural and functional information obtained from brain imaging will enhance our understanding of how the brain works and how its diseases can be cured.

From each speaker’s individual perspective and expertise, he or she will address the relationship between anatomical and functional connectivity. Target areas of the discussion will include:

1. Principles of spatiotemporal pattern formation

What spatiotemporal dynamics are possible given certain connectivity? Are there fundamental principles that can guide how we think about and study these dynamics?

2. Measuring connectivity and dynamics

What are the measures for anatomical and functional connectivity? How do they depend on each other? What are their underlying assumptions? What have they told us?

3. Clinical aspects of anatomical and functional connectivity

How are functions impaired when connections are severed? What type of “pathological” dynamics (e.g. epilepsy) can we avoid through changes of connectivity? To what extent are clinical conditions attributable to a loss of connections per se versus a reflection of new spatiotemporal dynamics?