“I love getting to know new people,” says Sandrine Muller, who will soon join DSI as a postdoctoral fellow. “I like to hear their stories and find out how where they came from shaped who they are.”

With her international upbringing–Muller was raised in Germany but spent a lot of time in France-–and facility with languages, Muller has been able to indulge her curiosity about people. That interest in people also drove her to pursue two undergraduate degrees – one in business and the other in psychology – and, interestingly, it was the former that sparked her interest in the latter.

As a DSI postdoc, Muller will call upon her knowledge of psychology to develop a smartphone-based app to screen for depression. Human resources was her focus at the Hamburg School of Business Administration, where she developed a particular interest in people’s workplace behavior.  After earning her business degree, she worked in human resources for corporations, an experience that solidified her interest in psychology.

“It was during this time that I discovered my interest in what drives people to behave in the ways they do, why and how they differ, and under what conditions people strive,” says Muller.

She determined to take her interest in psychology one step further as a student at the Dresden University of Technology, where for the first time she had a chance to do research. She got hooked on academic research while working as a lab assistant on a project about health and work ability in nurses. That research led her to Cambridge University, where she’s now completing a Ph.D. in psychology. As part of her doctoral studies, moreover, Muller was a visiting scholar at Disney Research’s Behavioral Science group in Pittsburgh; at the University of Texas at Austin; and at Stanford University. At Stanford, she worked on a large-scale smartphone sensing study, examining what smartphone data, especially a person’s mobility patterns, can reveal about his or her psychological state.

It is the Stanford work that leads her to DSI, where with guidance from advisers Sandra Matz at the Columbia Business School and Augustin Chaintreau from the Computer Science Department, she aims to design a smartphone-based screening system that can detect whether a person is depressed and make suggestions that could elevate his or her mood.

The opportunity to practice data-driven psychology excites Muller.

“A smartphone-based system that provides interventions at exactly the right time using the most effective treatment for a particular individual holds great promise for improving people’s mental and physical health,” she says. “Ultimately, I think that such forms of personalized, data-driven interventions are the future of psychology.”

For her project, Muller is collaborating with a German startup called Moodpath that markets a depression-screening app. In a pilot study, she’ll collect data from an initial sample of some 5,000 participants on their mobility patterns and mood reports. People who download the app will be informed of the details of the study and can give their consent to share their data, which will be protected. Participants will have the right to drop out of the study at any point and ask that their data be deleted.

Right now, Moodpath’s depression screening is based solely on questionnaires; the app messages users several times a day asking them to respond to short questions about symptoms they are experiencing and their daily activities. Moodpath will soon add a GPS-sensing module to its app that will track participants’ mobility patterns. And those mobility patterns could be central to understanding participants’ moods, including, possibly, the onset of depression. Some of the mobility data that Muller will collect include time spent at home, frequency or duration of visits to social places, distance traveled, time spent in green spaces, temporal stability and variability of places visited. She’s aiming to use that GPS data to complement the self-reported screening information now collected by Moodpath.

Research shows that depression can be marked by a change in behaviors, and the mobility data should allow her to detect behavior changes in participants. For instance, people experiencing depressive episodes might start to leave home less often, socially isolate themselves, visit fewer places, and become less physically active compared with non-depressed people. Moodpath currently uses in-app surveys – users respond to several questions a day – to track and corroborate mobility changes that could signal depression in users.

“There has been some initial work in this area but it’s essentially a brand-new field of research enabled by the emergence of ubiquitous smartphones, and we are adding a large-scale and in-depth investigation of depression,” says Mueller. “This enhanced understanding could help us ultimately improve the lives of those suffering from this pernicious and all-too-common mental illness.”

Overall all, smartphones could be an important tool in understanding human emotions, adds Muller. Understanding human psychology depends on observation, but it would be time-consuming, expensive and intrusive for a researcher to follow “you around 24/7 with a notepad.” Meanwhile, smartphones are becoming extremely effective tools for scientific research.

“Smartphones are a behavioral scientist’s dream come true,” says Muller, “as they allow us to collect fine-grained behavioral data in a nonintrusive, cost-efficient and continuous manner. I think it’s an exciting method that will become more and more common in social-science research. DSI’s mission to use data for good, moreover, strongly resonates with me and I’m honored and excited to be joining this terrific, interdisciplinary group of scholars.”

 

— Robert Florida