We are pleased to host a seminar by Yuhang Xu titled Bringing Innovative Clinical Maternal Health Monitoring Home: The Potential of Electrohysterogram (EHG)-Based Wearable Solutions. Dr. Xu will discuss emerging approaches for home-based maternal health monitoring using wearable technologies that capture uterine electrical activity through electrohysterography (EHG). Dr. Xu received her PhD in Electronic Engineering from King’s College London and is currently an Associate Professor at Coventry University. A Q&A session will follow the talk. Please join us for this exciting discussion at the forefront of maternal health and digital biomarker discovery!

The ROOTS study (Revealing cognitive Outcomes in “zeroth gen” Older immigranTS) has received a two-year R21 grant from the National Institute on Aging (R21AG096539). This project will recruit 100 older Chinese immigrants to examine how acculturative stress influences sleep and circadian health and how these factors relate to cognitive function. Findings from ROOTS will lay the groundwork for a future large-scale longitudinal study to better understand resilience and cognitive aging in immigrant communities.

In this study, we leveraged longitudinal actigraphy and neuropathological data from the Rush Memory and Aging Project to examine how when and how consistently older adults nap during the day are linked to their risk for Alzheimer’s disease (AD). We found that morning naps (9–11 AM) were associated with increased risk of Alzheimer’s dementia; early afternoon naps (1–3 PM) were linked to lower amyloid-β burden, a key AD pathology; and greater day-to-day variability in nap duration was associated with increased levels of amyloid-β and tau tangles at death. These results support a multi-dimensional sleep health framework and highlight that nap timing and regularity–not just duration–may be critical behavioral signals for brain aging. Congratulations to first author Dr. Chenlu Gao and the entire collaborative team!

We are excited to share that Dr. Peng Li has been appointed as an Associate Preceptor in the NIH-funded T32 Training Program in Sleep, Circadian, and Respiratory Neurobiology at Harvard Medical School, effective May 9, 2025. This role recognizes Dr. Li’s dedication to mentorship and allows him to sponsor and support trainees within this prestigious program. This highly regarded NIH-funded T32 training program–based in the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital–supports the next generation of scientists committed to advancing research in sleep and circadian biology. As an Associate Preceptor, Dr. Li is now formally recognized as a mentor qualified to sponsor trainees within the program, with the support of a Full Preceptor. Postdoctoral Fellows in Dr. Li’s lab may now be eligible to apply for T32 support, including salary, training-related expenses, and tuition, pending program requirements and funding availability. Please join us in congratulating Dr. Li on this well-deserved recognition!

Dr. Peng Li and Dr. Kun Hu co-authored an editorial in SLEEP journal (Volume 48, Issue 5), highlighting how disruptions in rest-activity rhythms (RARs) are associated with neurobiological changes linked to Alzheimer’s disease and dementia. The editorial synthesizes emerging evidence that fragmented or unstable RARs may precede clinical symptoms and are tied to structural brain changes, underscoring the importance of circadian health in aging and neurodegeneration. This work advocates for systems-level approaches to better understand circadian dysfunction as a modifiable risk factor for Alzheimer’s disease.

In this large longitudinal study of over 500 older adults, we found that lower complexity in pulse rate – a marker of cardiac autonomic function – is associated with faster cognitive decline over time. Notably, this novel nonlinear measure outperformed traditional heart rate variability metrics, highlighting the potential of digital health tools to improve early detection of dementia risk. We are deeply grateful to the BrightFocus Foundation for generously supporting this research. Congratulations to first author Dr. Chenlu Gao and the entire team!

We are pleased to host Dr. Xiaoqing Hu, Associate Professor at the University of Hong Kong, for an engaging seminar on Editing Unwanted Memories during Sleep. The seminar will take place on April 1, 2025 at 3:30 PM. See the poster before for location and registration. Dr. Hu will explore how sleep influences memory suppression, emotional regulation, and cognitive processing. A Q&A session will follow the talk. Please join us for this exciting discussion at the forefront of sleep and memory research!

We are thrilled to announce the launch of our new website for the Laboratory for Sleep and Digital Health! The site will serve as a hub for our latest research, projects, and innovations in sleep, circadian rhythms, and digital biomarkers for brain health. Stay tuned for updates, publications, and resources as we continue to advance the field and promote healthy cognitive aging. Visit us at LSDH to learn more! Our mirror site, hosted on GitHub, will remain live for continued access.

Dr. Chenlu Gao has successfully completed her first marathon at the Paris 2024 Marathon Pour Tous! This year’s Marathon Pour Tous made history by sharing the same course as the official Paris Olympic marathon, marking a first in Olympic history. Chenlu was among over 40,000 public participants who took on this challenge. Congratulations to Dr. Gao on this remarkable achievement!

Our PI Dr. Li recently taught a course during an online international summer school program hosted by China Pharmaceutical University. The 16-hour, one-credit course introduced students to statistical analysis using MATLAB, offering hands-on experience with fundamental techniques and tools. Dr. Li’s expertise in computational data analysis provided students with valuable insights and practical skills in statistical analysis. Congratulations to Dr. Li for contributing to this enriching educational experience!

A measure derived from actigraphy for the fractal fluctuation patterns of rest-activity delineates cognitive resilience. It was associated with cognitive decline after regressing out ten neuropathologies related to dementia, explaining an up to 5% variance in cognitive decline on top of and beyond about 35% variance explained by pathologies.

The Li Lab is pleased to accept a gift from a generous philanthropy donor. The fund will be used for wearable sleep detection advancement.

Dr. Li was appointed to an Assistant Editor in the esteemed American Heart Association (AHA) journal – Journal of the American Heart Association. In 2024, the Journal expanded its Early Career Program to include a group of Assistant Editors. Dr. Li is one of the ten newly recruited Assistant Editors in this journal.

From 2024, Dr. Li started serving on the Editorial Board of SLEEP, the most regarded journal in the field of sleep medicine and the No. 1 journal in sleep researchers’ ranking of sleep journals.

Drs. Li and Hu guest-edited a special issue highlighting how circadian rhythms — the body’s internal clocks — change with aging and contribute to the risk of age-related diseases. The issue features cutting-edge reviews and original research on the role of circadian disruptions in mood, metabolic, and cognitive health.

Frailty, or age-related decline in physiological function, is a common condition in older populations that increases their vulnerability to adverse health outcomes. We found a longitudinal association between disturbances in daily patterns of rest and activity, or circadian rest-activity rhythms, and higher risk of occurrence and progression of frailty over time.

Dr. Li just started his new role as an Assistant Professor of Anethesia at Department of Anesthesia, Critical Care and Pain Medicine (DACCPM) at Massachusetts General Hospital, Harvard Medical School. He will be leading a new research lab within the DACCPM.

Delirium is a complex neurocognitive syndrome suspected to be bidirectionally linked to dementia. We found that 24-hour daily suppression in rest activity rhythms, fragmentated rhythms, and potentially delayed acrophase were associated with delirium risk. Subsequent progression to dementia was more likely in delirium cases with suppressed rhythms.

Dr. Peng Li is award the 2022 Early Career Mentoring Award by the Department of Medicine (DOM), Brigham and Women’s Hospital. The Early Career Mentoring Award was established in 2011 to recognize the efforts of early career faculty who demonstrates effective mentoring through guiding and encouraging the career development of DOM residents, fellows, and/or faculty.