The Budapest Reference Connectome server computes the frequently appearing anatomical brain connections of 418 healthy subjects. It has been prepared from

diffusion MRI Diffusion-weighted magnetic resonance imaging (DWI or DW-MRI) is the use of specific MRI sequences as well as software that generates images from the resulting data that uses the diffusion of water molecules to generate contrast in MR images. It ...

datasets of the

Human Connectome Project The Human Connectome Project (HCP) is a five-year project sponsored by sixteen components of the National Institutes of Health, split between two consortia of research institutions. The project was launched in July 2009 as the first of three Grand ...

into a reference connectome (or brain

graph Graph may refer to: Mathematics *Graph (discrete mathematics), a structure made of vertices and edges **Graph theory, the study of such graphs and their properties *Graph (topology), a topological space resembling a graph in the sense of discre ...

), which can be downloaded in CSV and GraphML formats and visualized on the site in 3D.

Features

The Budapest Reference Connectome has 1015 nodes, corresponding to anatomically identified gray matter areas. The user can set numerous parameters and the resulting consensus connectome is readily visualized on the webpage. Users can zoom, rotate, and query the anatomical label of the nodes on the graphical component.

Background

Budapest Reference Connectome is a consensus graph of the brain graphs of 96 subjects in Version 2 and 418 subjects in Version 3. Only those edges are returned which are present in a given percentage of the subjects. Each of the selected edges has a certain weight in each of the graphs containing that edge, so these multiple weights are combined into a single weight, by taking either their mean (i.e., average) or median. The user interface allows the customization of these parameters: the user can select the minimum frequency of the edges returned. There is an option for viewing and comparing the female or male reference connectomes. The connectomes of women contain significantly more edges than those of men, and a larger portion of the edges in the connectomes of women run between the two hemispheres.

Discoveries

The Budapest Reference Connectome has led the researchers to the discovery of the Consensus Connectome Dynamics of the human brain graphs. The edges appeared in all of the brain graphs form a connected subgraph around the

brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...

. By allowing gradually less frequent edges, this core subgraph grows continuously, as a

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

. The growth dynamics may reflect the individual

brain development The development of the nervous system, or neural development (neurodevelopment), refers to the processes that generate, shape, and reshape the nervous system of animals, from the earliest stages of embryonic development to adulthood. The fiel ...

and provide an opportunity to direct some edges of the human consensus brain graph.

References

{{reflist Computational neuroscience Neuroscience Neuroinformatics Bioinformatics software