Rick Nelson

Body DAQ presents health, entertainment opportunities
October 17, 2008

LEUVEN, BELGIUM. In the latest twist on data acquisition, IMEC has developed what it calls an ambulatory arousal monitor. In a presentation at the IMEC Annual Research Review Meeting October 14, Bert Gyselinckx said that such a monitor can have applications ranging from entertainment to health care.

Gyselinckx, who is program director for IMEC at the Holst Centre—an independent R&D center established in 2005 by IMEC and Netherlands-based TNO—suggested that entertainment seems to be the primary application for precursors to the IMEC technology. He cited the Emotiv Systems mind/game interface as an example. But there are be practical applications as well. As an example in this category, he cited the Nissan Pivo2 Pivo-kun dashbot—a dashboard-mounted camera-based system that, by detecting a driver’s facial expression, can detect driver stress or drowsiness levels and take appropriate actions, such as advising the driver to calm down or take a break.

IMEC’s approach is a body-area network that consists of two ultra-low-power DSP-based wireless sensing nodes that measure autonomic nervous system responses. The first node is integrated in a chest belt and measures respiration and ECG (electrocardiogram or heart activity) based on IMEC’s proprietary single-channel biopotential ASIC. The second—integrated in a wristband—consists of a commercial sensor for skin temperature measurement and a dedicated circuit board for measuring the galvanic skin conductance between two fingers. The system, Gyselinckx said, consumes twenty times less power than a comparable Bluetooth device, allowing several days of autonomy on a commercial battery. The nodes connect to a PC that acts as a base station that runs software that derives in real time a person’s arousal level based on the physiological inputs. Ultimately, said Gyselinckx, IMEC researchers hope to use energy-harvesting techniques to make the system fully autonomous.

Functionally, the operation of the emotion-sensing system is not new, Gyselinckx said. Polygraphs dating from the 1930s measured relative blood pressure, heart rate, oxygenation of the blood, respiration, and electrical skin resistance. The IMEC system’s overwhelming advantage in comparison to such systems is its compact size. But IMEC is working on expanding the system’s functionality beyond what polygraphs can provide. One goal is to develop sensors and algorithms that can determine not just the magnitude of arousal (from high to low) but also the valence. Gyselinckx presented an x-y plot with the y axis representing arousal level or magnitude (positive direction indicates high magnitude), while x-axis values represent pleasure (positive half-plane) and displeasure (negative half-plane). Such a representation, he said, permits derivation of sentiments such as fear, anger, and frustration (upper left quadrant); excitement, delight, and happiness (upper right quadrant); contentment, relaxation, and sleepiness (lower right quadrant); and ennui, fatigue, and misery (lower left quadrant). Such capabilities, he said, could be adapted to enable real-time mental health monitoring for stress management and to enable affective computing involving intelligent human-machine interaction. Finally, he said, the technology could make use of a user’s state of alertness to optimize learning effectiveness.

There are some cautions to keep in mind when considering the widespread application of this technology. One early example of the technology that Gyselinckx cited is the Philips Vibe necklace, which can read multiple biometric signals of the person wearing it wearer and communicate those signals to other devices and other wearers. It might be one thing to wear your heart on your sleeve, but do you really want to wear jewelry or clothing that broadcasts your emotional state? I would advise caution.

Posted by Rick Nelson on October 17, 2008 | Comments (0)