Each user represents an individual researcher and is also a member of some laboratory. In order to access most functions within the portal, a researcher must obtain a user account. Once an account is created, the researcher can login to the portal and start the process of creating an experiment entry. When creating an experiment entry, the researcher enters MINEMO information through a series of HTML forms. The metadata fields correspond with entities in the NEMO ontology; in other words, we capture through the portal a complete description of an experiment, consistent with the standard established by the NEMO ontology and by the MINEMO checklist. To assist portal users, we created a tooltip mechanism that overlays ontology information directly on any form item when the user hovers their mouse pointer over that item. If the user is unsure of the meaning of an item while filling out a form, they can quickly lookup the ontology definition of that item using the tooltip overlay, as depicted in Figure 2. Figure 2 Sample metadata field in NEMO portal and illustration of “tooltips.” All form information is saved to an SQL database. Saved experiments can be edited at any time, and previously entered information can be copied and modified for inclusion in new entries, to reduce redundant data entry. Figure 3 gives a conceptual overview of how the NEMO portal and database make contact with the NEMO ontology and MI checklist. Notice that experiment metadata are written out to RDF (Figure 3, bottom right) and are then combined with the RDF representation of spatial and temporal metrics, which are stored in a Results Database. Figure 3 Overview of links between NEMO portal, database, ontology and MI checklist. Once experiment metadata have been captured in RDF, they can then be combined with the spatial and temporal metrics to provide a complete description of ERP patterns for input to classification and meta-analysis. Summary and conclusion Community participation NEMO is a relatively new project, and our initial efforts have been focused on developing and testing ERP ontologies and ontology-based tools for analysis. Our next step will be to apply these methods and tools to high-dimensional ERP datasets (with 100 EEG sensors or more) that have been collected across our research sites and to report findings from our first cross-lab, cross-experiment meta-analysis. Once we have provided this important “proof of concept,” we will solicit feedback from the wider clinical and cognitive neuroscience communities. All NEMO ontology (owl) files and NEMO ERP analysis and RDF generation code are freely available from our source forge repository [24]. Documentation is available from our Wiki [25]. We encourage members of the community to browse and download these resources and to provide feedback to our development team. To this end, we have established a public listserv [26].