One day, your computer will empathize with you. It will know if you're too tired (too much work) or bored (nothing to do/no work no nothing). A non-invasive and easily portable imaging technology developed at Tufts University will deliver the computer with real-time insight into a subject's more subtle emotional symptoms.
"One moment a user may be bored, and the next moment, the same user may be overwhelmed. Measuring mental workload, frustration and distraction is typically limited to qualitatively observing computer users or to administering surveys after completion of a task, potentially missing valuable insight into the users' changing experiences," said co-author Robert Jacob, computer science professor and researcher.
His human-computer interaction (HCI) group is collaborating with Sergio Fantini, biomedical engineering professor, for effective functional near-infrared spectroscopy (fNIRS) technology, employing light to constantly assess brain blood flow as a measure
of workload experienced by subjects while accomplishing an increasingly difficult task. The device mixes real-time biomedical data with machine learning. "fNIRS is an emerging non-invasive, lightweight imaging tool which can measure blood oxygenation levels in the brain," said Fantini, an associate dean for graduate education at Tufts' School of Engineering.
The fNIRS appears like a futuristic headband, having laser diodes emitting near-infrared light through the forehead at shallow depth (2-3 cm or 0.8-1.2 in) towards the brain's frontal lobe. Light crosses the tissues till they find blood hemoglobin, then absorbs it, and the remaining light is diffusely reflected to the fNIRS detectors. "fNIRS, like MRI, uses the idea that blood flow changes to compensate for the increased metabolic demands of the area of the brain that's being used," said Erin Solovey, a graduate researcher at the School of Engineering.
"We don't know how specific we can be about identifying users' different emotional states. However, the particular area of the brain where the blood flow change occurs should provide indications of the brain metabolic changes and by extension workload, which could be a proxy for emotions like frustration.", said Fantini.
Subjects wearing the fNIRS device were required to watch a multicolored cube made up of eight smaller cubes and displaying two, three or four different colors. While the cube was rotating onscreen, the volunteers had to determine the amount of colored squares in a group of 30 tasks. The fNIRS revealed higher effort with the increasing difficulty of the task, matching user surveys in about 83 % of the time. "It seems that we can predict, with relatively high confidence, whether the subject was experiencing no workload, low workload, or high workload", said co-author Leanne Hirshfield.