Publications

LENS: LLM-Enabled Narrative Synthesis for Mental Health by Aligning Multimodal Sensing with Language Models.

Wenxuan Xu*, Arvind Pillai*, Tess Griffin, Amanda C Collins, Michael Heinz, Damien Lekkas, Shayan Mirjafari, Matthew Nemesure, George Price, Nicholas Jacobson, Andrew Campbell. (*equal contribution)

ACL 2026 (Main) — Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

Learning Transferable Sensor Models via Language-Informed Pretraining

Yuliang Chen, Arvind Pillai, Yu Wu, Tess Z Griffin, Lisa Marsch, Michael V Heinz, Nicholas C Jacobson, Andrew Campbell

ICLR 2026 TSALM Workshop — 1st ICLR Workshop on Time Series in the Age of Large Models

Interindividual Differences in Digital Phenotypes of Major Depressive Disorder: A Passive Sensing Study Using Smartphone and Wearable Sensor Data

Elizabeth W Lampe, Amanda C Collins, Ahhyun Lee, Nicholas Enbar-Salo, Tess Z Griffin, Arvind Pillai, Michael V Heinz, Damien Lekkas, Matthew D Nemesure, Daniel M Mackin, Subigya Nepal, Andrew T Campbell, Nicholas C Jacobson

Behaviour Research and Therapy

Passive data do not improve prediction or detection of alcohol consumption beyond temporal patterns in major depression: A 90-day cross-validated study

Anna M Langener, Dawson Haddox, Daniel M Mackin, George D Price, Damien Lekkas, Amanda C Collins, Tess Z Griffin, Michael V Heinz, Matthew D Nemesure, Subigya Nepal, Arvind Pillai, Andrew T Campbell, Nicholas C Jacobson

Addictive Behaviors

Time2Lang: Bridging Time-Series Foundation Models and Large Language Models for Health Sensing Beyond Prompting

Arvind Pillai, Dimitris Spathis, Subigya Nepal, Amanda C Collins, Daniel M Mackin, Michael V Heinz, Tess Z Griffin, Nicholas C Jacobson, Andrew Campbell

CHIL 2025 — Conference on Health, Inference, and Learning

PaPaGei: Open Foundation Models for Optical Physiological Signals

Arvind Pillai, Dimitris Spathis, Fahim Kawsar, Mohammad Malekzadeh

ICLR 2025 — International Conference on Learning Representations

MindScape Study: Integrating LLM and Behavioral Sensing for Personalized AI-Driven Journaling Experiences

Subigya Nepal, Arvind Pillai, William Campbell, Talie Massachi, Michael V Heinz, Ashmita Kunwar, Eunsol Soul Choi, Orson Xu, Joanna Kuc, Jeremy Huckins, et al.

UbiComp 2025 — Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies

Psychometric properties and validity of a Mobile Patient Health Questionnaire-9 (MPHQ-9) for ecological momentary assessment in depressed adults

Dawson Haddox, Daniel M Mackin, Tess Z Griffin, Michael V Heinz, Matthew D Nemesure, Amanda C Collins, George D Price, Damien Lekkas, Arvind Pillai, Subigya Nepal, Andrew T Campbell, Nicholas C Jacobson

Psychological Assessment

Acute suicidal ideation in context: highlighting sentiment-based markers through the diary entries of a clinically depressed sample

Damien Lekkas, Amanda C Collins, Michael V Heinz, Tess Z Griffin, Arvind Pillai, Subigya K Nepal, Daniel M Mackin, Andrew T Campbell, Nicholas C Jacobson

BMC Psychiatry

Anhedonia in flux: Understanding the associations of emotion regulation and anxiety with anhedonia dynamics in a sample with major depressive disorder

Michael R Gallagher, Amanda C Collins, Damien Lekkas, Matthew D Nemesure, Tess Z Griffin, George D Price, Michael V Heinz, Arvind Pillai, Subigya Nepal, Daniel M Mackin, Andrew T Campbell, E Samuel Winer, Nicholas C Jacobson

Journal of Affective Disorders

Capturing the College Experience: A Four-Year Mobile Sensing Study of Mental Health, Resilience and Behavior of College Students during the Pandemic

Subigya Nepal, Wenjun Liu, Arvind Pillai, Weichen Wang, Vlado Vojdanovski, Jeremy F Huckins, Courtney Rogers, Meghan L Meyer, Andrew T Campbell

UbiComp 2024 — Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies

MoodCapture: Depression Detection Using In-the-Wild Smartphone Images

Subigya Nepal*, Arvind Pillai*, Weichen Wang, Tess Griffin, Amanda C Collins, Michael Heinz, Damien Lekkas, Shayan Mirjafari, Matthew Nemesure, George Price, et al. (*co-primary)

CHI 2024 — Proceedings of the CHI Conference on Human Factors in Computing Systems

Contextual AI Journaling: Integrating LLM and Time Series Behavioral Sensing Technology to Promote Self-Reflection and Well-being using the MindScape App

Subigya Nepal, Arvind Pillai, William Campbell, Talie Massachi, Eunsol Soul Choi, Xuhai Xu, Joanna Kuc, Jeremy F Huckins, Jason Holden, Colin Depp, et al.

CHI EA 2024 — Extended Abstracts of the CHI Conference on Human Factors in Computing Systems

Investigating Generalizability of Speech-based Suicidal Ideation Detection Using Mobile Phones

Arvind Pillai, Subigya Kumar Nepal, Weichen Wang, Matthew Nemesure, Michael Heinz, George Price, Damien Lekkas, Amanda C Collins, Tess Griffin, Benjamin Buck, et al.

UbiComp 2024 — Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies

Social Isolation and Serious Mental Illness: The Role of Context-Aware Mobile Interventions

Subigya Nepal*, Arvind Pillai*, Emma M Parrish, Jason Holden, Colin Depp, Andrew T Campbell, Eric L Granholm (*co-primary)

IEEE Pervasive Computing

The role of borderline personality disorder traits in predicting longitudinal variability of major depressive symptoms among a sample of depressed adults

Emily A Kline, Damien Lekkas, Anastasia Bryan, Matthew D Nemesure, Tess Z Griffin, Amanda C Collins, George D Price, Michael V Heinz, Subigya Nepal, Arvind Pillai, et al.

Journal of Affective Disorders

From Mood to Use: Using Ecological Momentary Assessments to Examine How Anhedonia and Depressed Mood Impact Cannabis Use in a Depressed Sample

Amanda C Collins, Damien Lekkas, Cara A Struble, Brianna M Trudeau, Abi D Jewett, Tess Z Griffin, Matthew D Nemesure, George D Price, Michael V Heinz, Subigya Nepal, Arvind Pillai, et al.

Psychiatry Research

Depressive symptoms as a heterogeneous and constantly evolving dynamical system: Idiographic depressive symptom networks of rapid symptom changes among persons with major depressive disorder

Matthew D Nemesure, Amanda C Collins, George D Price, Tess Z Griffin, Arvind Pillai, Subigya Nepal, Michael V Heinz, Damien Lekkas, Andrew T Campbell, Nicholas C Jacobson

Journal of Psychopathology and Clinical Science

Rare Life Event Detection via Mobile Sensing Using Multi-Task Learning

Arvind Pillai, Subigya Nepal, Andrew Campbell

CHIL 2023 — Conference on Health, Inference, and Learning

First-Gen Lens: Assessing Mental Health of First-Generation Students across Their First Year at College Using Mobile Sensing

Weichen Wang, Subigya Nepal, Jeremy F Huckins, Lessley Hernandez, Vlado Vojdanovski, Dante Mack, Jane Plomp, Arvind Pillai, Mikio Obuchi, Alex daSilva, et al.

UbiComp 2023 — Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies

Accurate Step Count with Generalized and Personalized Deep Learning on Accelerometer Data

Long Luu, Arvind Pillai, Halsey Lea, Ruben Buendia, Faisal M Khan, Glynn Dennis

Sensors

Machine Learning Enabled Non-invasive Diagnosis of Nonalcoholic Fatty Liver Disease and Assessment of Abdominal Fat from MRI Data

Arvind Pillai, Kamen Bliznashki, Emmette Hutchison, Chanchal Kumar, Benjamin Challis, Mishal Patel

ML4H @ NeurIPS 2020 — Workshop on Machine Learning for Health

Personalized Step Counting Using Wearable Sensors: A Domain Adapted LSTM Network Approach

Arvind Pillai, Halsey Lea, Faisal Khan, Glynn Dennis

PharML @ ECML 2020 — Workshop on Pharmaceutical Machine Learning

Graph Convolutional Networks for Predicting Drug-Protein Interactions

Hafez Eslami Manoochehri, Arvind Pillai, Mehrdad Nourani

IEEE BIBM 2019 — IEEE International Conference on Bioinformatics and Biomedicine

Local Diagonal Extrema Number Pattern: A New Feature Descriptor for Face Recognition

Arvind Pillai, Rajkumar Soundrapandiyan, Swapnil Satapathy, Suresh Chandra Satapathy, Ki-Hyun Jung, Rajakumar Krishnan

Future Generation Computer Systems (FGCS)