Study Objectives To compare estimated epileptic source localizations from 5 sleep-wake states (SWS): wakefulness (W), rapid eye movement sleep (REM), and non-REM 1-3. Methods Electrical source localization (sLORETA) of interictal spikes from different SWS on surface EEG from the epilepsy monitoring unit at spike peak and take-off, with results mapped to individual brain models for 75% of patients. Concordance was defined as source localization voxels shared between 2-5 SWS, and discordance as those unique to 1 SWS against 1-4 other SWS. Results 563 spikes from 16 prospectively recruited focal epilepsy patients across 161 day-nights. SWS exerted significant differences at spike peak but not take-off. Source localization size did not vary between SWS. REM localizations were smaller in multifocal than unifocal patients (28.8% vs. 54.4%, p=0.0091). All 5 SWS contributed about 45% of their localizations to converge onto 17.0±15.5% voxels. Against any one other SWS, REM was least concordant (54.4% vs. 66.9%, p=0.0006) and most discordant (39.3% vs. 29.6%, p=0.0008). REM also yielded the most unique localizations (20.0% vs. 8.6%, p=0.0059). Conclusions REM was best suited to identify candidate epileptic sources. sLORETA proposes a model in which an “omni-concordant core” of source localizations shared by all 5 SWS is surrounded by a “penumbra” of source localizations shared by some but not all SWS. Uniquely, REM spares this core to “move” source voxels from the penumbra to unique cortex not localized by other SWS. This may reflect differential intra-spike propagation in REM, which may account for its reported superior localizing abilities.

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This research examined the usability and effectiveness of wayfinding in multiple large, complex, multi-building hospitals. The initial research explored three large hospitals’ touchscreen wayfinding interfaces. Errors and issues consistently observed were organized and developed into heuristics and design recommendations. In phase two, a promising mobile application was chosen and both a heuristic analysis and an onsite test of effectiveness were conducted by four researchers. Though the application met many requirements and solved many issues from phase one, it did not meet the expectation of real time navigation. For phase three we chose an app that provided real time navigation and conducted a usability test onsite. Results indicate that this problem is multi-faceted and wayfinding solutions must consider the other available aids in the environment. Incorporation of user centered design principles and requiring the evaluations of users in the development of wayfinding aids are needed. Beyond usability, the key learning is that the wayfinding systems cannot be created in a vacuum, rather the interfaces, the placement of the wayfinding system and the environment of the hospital must be considered. The wayfinding kiosk or app information should complement the environmental information such as color coding, landmarks, room and elevator labeling and signage.

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