24 hour ambulatory research system supporting multiple physiologic sensors

Feasibility and performance evaluation of generating and recording visual evoked potentials using ambulatory Bluetooth based system

Report contains the design overview and key performance measurements demonstrating the feasibility of generating and recording ambulatory visual stimulus evoked potentials using the previously reported custom Complementary and Alternative Medicine physiologic data collection and monitoring system, CAMAS. The methods used to generate visual stimuli on a PDA device and the design of an optical coupling device to convert the display to an electrical waveform which is recorded by the CAMAS base unit are presented. The optical sensor signal, synchronized to the visual stimulus emulates the brain's synchronized EEG signal input to CAMAS normally reviewed for the evoked potential response. Most importantly, the PDA also sends a marker message over the wireless Bluetooth connection to the CAMAS base unit synchronized to the visual stimulus which is the critical averaging reference component to obtain VEP results. Results show the variance in the latency of the wireless marker messaging link is consistent enough to support the generation and recording of visual evoked potentials. The averaged sensor waveforms at multiple CPU speeds are presented and demonstrate suitability of the Bluetooth interface for portable ambulatory visual evoked potential implementation on our CAMAS platform.

Second generation complementary and alternative medicine physiologic data collection and monitoring research platform

Progress on our second generation portable system specifically designed to collect 24 hour ambulatory physiologic data from human subjects is reported. The upgraded system has more sensor flexibility and better performance and is smaller, lighter, and simpler to use than our previous version. The new system continues to support a wide variety of sensors found useful for complementary and alternative medicine (CAM) research and has been designed using a modular approach for future expansion of capabilities. The system has improved data storage and supports popular physiologic data formats. Support for wireless control and real-time data monitoring has been added which demonstrates capabilities to be used for physiologic feedback control. The system was designed specifically to support the needs of investigators studying CAM mind-body interventions but could be used for a variety of research needs.