The CIFTI 1.0 data file format was introduced in 2011 and is used extensively in the datasets publicly released by the Human Connectome Project (HCP, http://www.humanconnectome.org/). In the course of these efforts, the HCP software development team has encountered several limitations with the CIFTI 1.0 file format. We are currently drafting a proposal for CIFTI 2.0 that will include a number of refinements and new features that will be useful for handling of fMRI, MEG and tractography data. The proposed changes are relatively modest in scope, but they are not backwards-compatible with CIFTI 1.0. Hence, it is preferable to increment the version number.

A draft document for CIFTI 2.0 will be circulated soon to this forum, to the original CIFTI working group, and to others who request to join by responding to this forum. By this message, we encourage suggestions from others regarding desired design features or constraints that should be considered for the new CIFTI 2.0 format.

Several recent publications in a special issue of Neuroimage illustrate the utility of the CIFTI format for HCP data (Glasser et al.; http://www.ncbi.nlm.nih.gov/pubmed/23668... Smith et al.; http://www.ncbi.nlm.nih.gov/pubmed/23702...); and Barch et al., http://www.ncbi.nlm.nih.gov/pubmed/23684...)