Publications

My work spans computational modeling, physiological signal analysis, and clinically motivated applications in neurology and aging. Publications appear in interdisciplinary venues bridging engineering, medicine, and applied mathematics.

Selected Publications

A curated selection of representative work spanning physiological signal modeling, intervention design, and clinical translation.

  • **Chang, Joshua T., Alisha Ragatz, Anjana Ganesh, Ana P. Quiros Padilla*, Mikayla R. Devins, Christina V. Mihova, and John G. Milton. (2025).** “Center of Mass (CoM) Motions and Foot Placement During Treadmill Walking Using One Time-of-Flight Camera.” Sensors, 25(18): 5850. DOI: 10.3390/s25185850 Developed a vision-based system for quantifying gait dynamics, enabling accessible and scalable mobility assessment.

  • Hilsabeck, Robin C., Jeffrey N. Keller, Maya L. Henry, Junyi Jessy Li, Lokesh Pugalenthi, Paul Toprac, Patrick Chang, Joshua Chang, Suzanne Schmitz, Avery Largent, Heather Foil. (2025). “Development and classification accuracy of an automated cognitive screening tool combining working memory and connected speech tasks for early detection of cognitive impairment in primary care.” Alzheimer’s & Dementia: TRCI, 11(3): e70145. DOI: 10.1002/trc2.70145 Developed a scalable cognitive screening tool combining speech and working memory tasks for early detection in primary care.

  • Paydarfar, Daniel A., David Paydarfar, Peter J. Mucha, and Joshua Chang. (2021). “Optimizing emergency stroke transport strategies using physiological models.” Stroke, 52(12): 4010–4020. DOI: 10.1161/STROKEAHA.120.031633 Applied physiological modeling to optimize emergency stroke transport strategies and improve time-sensitive clinical decisions.

  • Chang, Joshua, and David Paydarfar. (2021). “Falling off a limit cycle using phase-agnostic stimuli: Applications to clinical oscillopathies.” Chaos, 31(2): 023134. DOI: 10.1063/5.0032974 Demonstrated how phase-independent stimulation can robustly altar oscillatory biological systems with applications to clinical disorders.

  • Chang, Joshua, and David Paydarfar. (2019). “Optimizing stimulus waveforms for electroceuticals.” Biological Cybernetics, 113(1): 191–199. DOI: 10.1007/s00422-018-0774-x Introduced methods for optimizing stimulation waveforms, enabling more efficient and selective neuromodulation strategies.

  • Chang, Joshua, and David Paydarfar. (2018). “Evolution of extrema features reveals optimal stimuli for biological state transitions.” Scientific Reports, 8(1): 1–13. DOI: 10.1038/s41598-018-21761-8 Developed a framework for identifying optimal stimuli to drive transitions in biological systems linking signal features to intervention design. —

Full Publication List

A complete list of publications is provided below.

  • **Chang, Joshua T., Alisha Ragatz, Anjana Ganesh, Ana P. Quiros Padilla*, Mikayla R. Devins, Christina V. Mihova, and John G. Milton. (2025).** “Center of Mass (CoM) Motions and Foot Placement During Treadmill Walking Using One Time-of-Flight Camera.” Sensors, 25(18): 5850. DOI: 10.3390/s25185850

  • Hilsabeck, Robin C., Jeffrey N. Keller, Maya L. Henry, Junyi Jessy Li, Lokesh Pugalenthi, Paul Toprac, Patrick Chang, Joshua Chang, Suzanne Schmitz, Avery Largent, Heather Foil. (2025). “Development and classification accuracy of an automated cognitive screening tool combining working memory and connected speech tasks for early detection of cognitive impairment in primary care.” Alzheimer’s & Dementia: TRCI, 11(3): e70145. DOI: 10.1002/trc2.70145

  • **Epstein, Sophia*, Joshua Chang, Daniel Johnston, and David Paydarfar. (2024).** “Size principles governing selective neuromodulation and recruitment order of nerve fibers.” Current Opinion in Biomedical Engineering. DOI: 10.1016/j.cobme.2025.100583

  • **Debnath, Minakshi*, Joshua Chang†, Keshav Bhandari, Dalma J. Nagy, Tamas Insperger, John G. Milton, and Anne H. H. Ngu. (2024).** “Pole balancing on the fingertip: model-motivated machine learning forecasting of falls.” Frontiers in Physiology, 15: 1334396. DOI: 10.3389/fphys.2024.1334396

  • Chang, Joshua, David Paydarfar, and John Milton. (2022). “Multistable neuromorphic computing: controlling attractor switches using waveforms.” 2022 International Electron Devices Meeting (IEDM). IEEE. DOI: 10.1109/IEDM45625.2022.10019427

  • **Paydarfar, Daniel A.*, David Paydarfar, Peter J. Mucha, and Joshua Chang. (2021).** “Optimizing emergency stroke transport strategies using physiological models.” Stroke, 52(12): 4010–4020. DOI: 10.1161/STROKEAHA.120.031633

  • **Rao, Nitya*, Joshua Chang, and David Paydarfar. (2021).** “Characterizing the performance of emergency medical transport time metrics in a residentially segregated community.” The American Journal of Emergency Medicine, 50: 111–119. DOI: 10.1016/j.ajem.2021.07.013

  • Chang, Joshua, and David Paydarfar. (2021). “Falling off a limit cycle using phase-agnostic stimuli: Applications to clinical oscillopathies.” Chaos, 31(2): 023134. DOI: 10.1063/5.0032974

  • **Chang, Joshua, Varun Sridhar*, and David Paydarfar. (2020).** “Falling off a limit cycle using phase-agnostic stimuli: Definitions and conceptual framework.” Chaos, 30(12): 123113. DOI: 10.1063/5.0026143

  • Ngu, Anne H., Vangelis Metsis, Shaun Coyne, Brian Chung, Rachel Pai, and Joshua Chang. (2020). “Personalized fall detection system.” 2020 IEEE International Conference on Pervasive Computing and Communications Workshops (PerCom Workshops). IEEE. DOI: PerComWorkshops48775.2020.9156172

  • Chang, Joshua, and David Paydarfar. (2019). “Optimizing stimulus waveforms for electroceuticals.” Biological Cybernetics, 113(1): 191–199. DOI: 10.1007/s00422-018-0774-x

  • Chang, Joshua, and David Paydarfar. (2018). “Optimizing stimulus waveforms for suppressing epileptic activity reveals a counterbalancing mechanism.” 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE. DOI: 10.1109/EMBC.2018.8512762

  • **Gee, Alan H.*, Joshua Chang, Joydeep Ghosh, and David Paydarfar. (2018).** “Bayesian online changepoint detection of physiological transitions.” 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE. DOI: 10.1109/EMBC.2018.8512204

  • Chang, Joshua, and David Paydarfar. (2018). “Evolution of extrema features reveals optimal stimuli for biological state transitions.” Scientific Reports, 8(1): 1–13. DOI: 10.1038/s41598-018-21761-8

  • Kubat Öktem, Elif, Karen Mruk, Joshua Chang, Ata Akin, William R. Kobertz, and Robert H. Brown Jr. (2016). “Mutant SOD1 protein increases Nav1.3 channel excitability.” Journal of Biological Physics, 42(3): 351–370. DOI: 10.1007/s10867-016-9411-x

  • Chang, Joshua, and David Paydarfar. (2015). “Optimal stimulus waveforms for eliciting a spike: How close is the spike-triggered average?” 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER). IEEE. DOI: 10.1109/NER.2015.7146647

  • Chang, Joshua, and David Paydarfar. (2014). “Switching neuronal state: optimal stimuli revealed using a stochastically-seeded gradient algorithm.” Journal of Computational Neuroscience, 37(3): 569–582. DOI: 10.1007/s10827-014-0525-5

  • Kim, Sun-Young, Steven Sweet, Joshua Chang and Sue J. Goldie. (2011). “Comparative evaluation of the potential impact of rotavirus versus HPV vaccination in GAVI-eligible countries: a preliminary analysis focused on the relative disease burden.” BMC Infectious Diseases, 11(1): 1–17. DOI: 10.1186/1471-2334-11-174

  • Jiang, Leaf A., Eric A. Dauler, and Joshua T. Chang. (2007). “Photon-number-resolving detector with 10 bits of resolution.” Physical Review A, 75(6): 062325. DOI: 10.1103/PhysRevA.75.062325