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To: fMRI Research Community From: National fMRI Data Center Re: Informational Memo July 15, 2000 As many of you know, a data repository for functional imaging studies is being established. From time to time informational memos will be sent to the fMRI Research community in order to provide background information about the activities of the Center and to respond to questions and concerns that have been raised by those interested in this enterprise. This is the first of such memos. General Background: Since the advent of technology for imaging the human brain in vivo over the last decade there has been a steady and predictable rise in the number of laboratories performing studies aiming to explore the landscape of cognitive function. Whereas early on, only a few, well funded medical centers were in a position to actively pursue these studies, the list of groups now conducting neuroimaging experimentation is considerable. Despite the popularity of neuroimaging, however, there remains little, if any, sharing of raw image data occurring amongst members of this widening community. Presently, heroic efforts are required by researchers to extract statistical values from the published literature in order to conduct meta-analytic assessment of neuroimaging findings (e.g. Cabeza and Nyberg, J. Cog. Neurosci., 12, 1-47). Previous pioneering work to design and establish an online repository for the results of imaging experiments helped to advance the concepts of more dynamic meta-analytic assessment of findings from across numerous reports (i.e. BrainMap, http://ric.uthscsa.edu/projects/brainmap.html). However, these efforts were undertaken prior to the newest generation of database tools that enables the storage, manipulation, and searching of extremely large image data sets such as those collected in fMRI. The National fMRI Data Center (http://www.fmridc.org) endeavors to act as the curator for such large data sets used to obtain results published in the leading peer reviewed journals, thereby enabling other researchers to download and reproduce experimental results, examine new data processing methodologies, and evaluate novel experimental designs. In this manner, fMRI can more easily draw on the knowledge-base of many disciplines, including Mathematics (e.g. image processing and statistics), Computer Science (e.g. data storage, compression, and management), as well as Neuroscience (e.g. interpretation of brain function). The storing of scientific data in online, readily accessible databases is certainly not a new idea and examples exist in many different areas of study. In each case, such repositories have been an integral element in speeding the progress in the relevant discipline, allowing researchers to compare and confirm results, and build on previous work. Most famous among such efforts is the Human Genome Project database (see Science, 288, 2294-2295, 2304-2307) which has, for some time, been continually updated and made available to anyone via the internet (http://www.ncbi.nlm.nih.gov), enabling researchers and laymen alike to inspect and examine genetic sequences. Companion to the Human Genome Project is the Protein Data Bank (http://www.rcsb.org/pdb) administered by the Research Collaboratory for Structural Bioinformatics (http://www.rcsb.org/index.html). This is the single international repository for the processing and distribution of 3-D macromolecular structure data, primarily determined experimentally by X-ray crystallography and nuclear magnetic resonance. The astronomical sciences have also made great progress by using shared data, and moreover, the huge expense of the equipment used in this field (e.g. telescopes, satellites) has necessitated such an approach. Particularly impressive is the remote sensing images acquired from the Mars Global Surveyor mission (http://mars.jpl.nasa.gov/mgs) that are currently being made available online to anyone within hours after the data's 1.6 million mile journey from our neighboring planet. Recent examination of these images has revealed evidence for the existence of water on Mars (Science, 288, 2330-2335). Additionally, the National Space Science Data Center (http://nssdc.gsfc.nasa.gov) makes available images and spacecraft telemetry data from a large number of NASA space missions. These data include Earth terrain and atmospheric measurements, solar activity data, as well as high-resolution images taken during human lunar activity. Additional representative databases for other fields can easily be located using any internet search engine. Analogously, in order for cognitive neuroscience, via the use of functional neuroimaging, to reach the goal of understanding the principles of brain function it is necessary to increase the number of neuroscientists and other researchers that can examine, consider, analyze and assess the brain imaging data that has already been collected and published. The ultimate goal of The National fMRI Data Center is to help facilitate this process by making available the raw data from these studies with the hope of advancing the understanding of the cognitive function and the neural substrates that underlie them. This publicly available database which is the National Data Center hopes to serve this function for the scientific community. The fMRI database project in many ways is more complex than the several other database systems just reviewed. The complexities of human experimentation require a demanding set of associated experimental information be linked to the brain images. The type of stimuli used and the variety of experimental paradigms will all have to be part of each set of data. Added to this is the reality that different laboratories use different storage formats for their experimentation. All of these aspects of fMRI research will be addressed by the Data Center and each author will be assisted in presenting the data to the Center. It is widely recognized that sometimes more information is collected in the process of a typical MRI study than is originally reported. In order to allow the authors more time to analyze their data, the data center will be following certain guidelines. In this regard, in a letter to the Office of Management and Budget, the President of the National Academy of Sciences stated that "permitting the researcher who actually collected the data to be the first to analyze and publish conclusions concerning the data is an essential motivational aspect of research" (http://www.nas.edu/includes/letter.htm). The National Data Center concurs with this sentiment and also with reports from the National Academy of Sciences, issued through the National Research Council, supporting the concept of data sharing (http://www.nas.edu/includes/letter.htm). Therefore, the Data Center will offer authors the option to place their data in a "data hold" for a fixed period of time where visitors to the data center may view only the published statistical data and not the underlying functional and anatomical data. This procedure has already been implemented in other communities, namely the Protein Data Bank (http://www.rcsb.org/pdb/nih-policy.html). As the Data Center continues to evolve, these policies will continue to be reviewed and refined with regard to the best interests of the fMRI community. In addition, our external advisory board, chaired by Dr. Marcus Raichle will continue to assess our activity and achievements. We look forward to working with the fMRI community. If you wish to be apprised of new developments at the center please visit us at http://www.fmridc.org. Sincerely, The National fMRI Data Center %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%