The Brain Connectivity Workshops: Moving the frontiers of computational systems neuroscience

Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London WC1N3BG, UK.
NeuroImage (Impact Factor: 6.36). 09/2008; 42(1):1-9. DOI: 10.1016/j.neuroimage.2008.04.167
Source: PubMed


Understanding the link between neurobiology and cognition requires that neuroscience moves beyond mere structure-function correlations. An explicit systems perspective is needed in which putative mechanisms of how brain function is
constrained by brain structure are mathematically formalized and made accessible for experimental investigation. Such a systems approach critically rests on a better understanding of brain connectivity in its various forms. Since 2002, frontier topics of connectivity and neural system analysis have been discussed in a multidisciplinary annual meeting, the Brain Connectivity Workshop (BCW), bringing together experimentalists and theorists from various fields. This article summarizes some of the main discussions at the two most recent workshops, 2006 at Sendai, Japan, and 2007 at Barcelona, Spain: (i) investigation of cortical micro- & macrocircuits, (ii)
models of neural dynamics at multiple scales, (iii) analysis of "resting state" networks, and (iv) linking anatomical to functional connectivity. Finally, we outline some central challenges and research trajectories in computational systems neuroscience for the next years.

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    • "Cognitive performance is known to be mediated by multiple interacting brain circuits and their connections (11). The integrity of this circuitry can be inferred from the degree of “functional connectivity,” which is based on the concept that intercorrelations between clusters of neural activity, recorded from different brain regions, reflect exchange of information (i.e., functional connectivity) between these regions (12,13). "
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    • "These mechanisms include gating and gain control mechanisms, which render synaptic transmission dependent on the current membrane potential and the history of other synaptic inputs nearby. These transient and nonlinear effects are important for explaining the dynamics of functional interactions among neuronal populations (Friston, 1995; McIntosh, 2000; Salinas and Sejnowski, 2001; Stephan et al., 2008). A second, and probably more important, reason why there is no one-to-one mapping between axonal and effective connectivity is that the structural presence, and even the molecular structure, of a particular synaptic connection does not determine whether it will be engaged during a particular functional process. "
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