By Linda Carroll

A wristband made of smart fabric may someday provide real-time insight into wearers’ emotions, researchers say.

The wristbands are designed to change color, pressure or temperature in response to changes in arousal levels. In a small preliminary trial, they alerted people to possible fluctuations in mood, researchers reported at the annual meeting of the Association for Computing Machinery in San Diego.

“The main message is that with relatively low costs, we can support people (becoming) more emotionally aware,” said the study’s lead author, Muhammad Umair, a research associate in the School of Computing and Communications at Lancaster University in the UK. “We think . . . most of us can benefit from being more aware and able to control or regulate our emotional responses.”

Umair and his colleagues investigated the use of wristbands made from thermochromic materials that change color, heat up, vibrate or squeeze the wrist, with changes in the conductivity of the skin of the user.

Ultimately, the researchers envision the wristbands being used to help people with depression, anxiety and bipolar disorders to monitor their emotions.

Manufacturers of smartwatches and fitness trackers are also trying to develop ways to track and respond to emotions, but Umair’s team hopes the novel forms of feedback their wristbands provide might mirror what the user is experiencing better than a standard digital display.

To test the fabric wristbands, the researchers recruited 12 men and women who had no prior experience with emotion-tracking devices. Six prototypes were randomly assigned to the volunteers.

“We used standard biosensors measuring skin conductance commonly associated with physiological arousal, which we integrated with our new actuators to provide a visual or tactile representation of the measured arousal,” Umair said in an email. “If we talk about sadness, then this is associated with low arousal and the device will most likely reflect low arousal. On the other hand, anxiety tends to be associated with high arousal, so the device will most likely reflect this. The devices do not differentiate between positive and negative emotions, but between high and low intensity ones.”

The volunteers were told to wear their wristbands for 48 hours as they went about their daily life. They were asked to keep a diary of any time the wristband alerted them to a change in mood. At the end of the second day, they were interviewed and asked about their experiences with the emotional monitoring.

The wristbands did appear to make people more self-aware. One volunteer, for example, felt his device heat up while he was talking about a disliked boss: “I knew it was telling me that, hey! You have negative emotions!” Later on, he said, “It gave me time to reflect on whether I should be angry or not that angry and then I learned I chose being angry.”

The researchers also found that some forms of feedback seemed more effective than others. Gradually rising heat from the wristband was too easily ignored by users, they noted, while graded colored lights seemed to convey the rise and fall of arousal levels in a way users found similar to the way they experienced shifts in mood.

Dr. Ahmed Hassoon noted that the wristbands and the feedback on mood they supposedly provide still need further study.

There could be factors other than fluctuations in emotions to explain the changes in heat, color or other sensations produced by the wristbands, said Hassoon, a research associate at the Johns Hopkins School of Public Health and in neurology at Johns Hopkins Medicine. “For example, one subject said he had a beer and something changed in his bracelet,” Hassoon said. “The alcohol could have triggered a response in his body and that might have been the signal detected by the bracelet.”

Hassoon has other concerns about the prospect of such devices, especially about privacy. “Imagine if in the future you have a device like this that records emotional responses,” he said. “Who would own that data? Would there be companies out there selling it? Could it affect hiring? Or could the data be sold to a marketing agency that would choose your weakest point of the day and start marketing products to you then?”

SOURCE: Proceedings of the Association for Computing Machinery conference on Designing Interactive Systems, June 2019.