Smart necklace uses heat signal to track smoking habits

Developed by researchers at Northwestern University, SmokeMon resembles a pendant or necklace. Tracking the heat signal given off by cigarettes, the device can detect when one is lit, how much smokers inhale, the time between drags, and the length of time the cigarette is in the mouth. Collectively, this information is known as smoking topography, and it is important data both for understanding smoking-related diseases and supporting people trying to quit the habit.

“We want to catch them before they completely fall off the wagon,” said senior investigator Nabil Alshurafa, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. “Once they do, it’s much harder for them to quit again.

“For many people who attempt to quit smoking, a slip is one or two cigarettes or even a single puff. But a slip is not the same as a relapse (going back to smoking regularly). A person can learn from slips, by gaining awareness that they did not fail, they just had a temporary setback. To avoid a relapse, we can then begin to shift their focus on how we handle their triggers and deal with cravings.”  

Alshurafa and colleagues recruited 19 participants for their study. Over the course of 115 smoking sessions, scientists examined their smoking behaviour in controlled and free-living experiments. As smokers wore the device, the team trained a deep learning-based machine model to detect smoking events along with their smoking topography, including things like timing of a puff, number of puffs, puff duration, puff volume, inter-puff interval and smoking duration. They also ran three focus groups with 18 tobacco-treatment specialists to understand how they felt about the device.

It is hoped that information gathered by the device can be used to predict when a person will relapse and when intervention – a phone call or text message - is needed to try to prevent a relapse. The scientists also plan to study the effectiveness of the device in detecting behaviour around electronic cigarettes. Their work is published in Proceedings of the ACM on Interactive, Mobile, Wearable, and Ubiquitous Technologies.

“Now we can begin to test the effectiveness of this device in improving the success rate of smoking cessation programs by preventing relapse in smokers who are planning to quit,” said Alshurafa. “We will be able to test whether real-time feedback and interventions can be more effective than usual care.”