# The Symptom Science of Excessive Daytime Sleepiness:  A Multidimensional Approach

> **NIH NIH R21** · UNIVERSITY OF WISCONSIN-MADISON · 2020 · $232,563

## Abstract

PROJECT SUMMARY/ABSTRACT
Excessive daytime sleepiness (EDS) is a very common symptom in the population, and has negative effects
on health and well-being across the life span. Despite the importance of EDS, little is known about the
biological changes in the brain associated with daytime somnolence, and objective measures currently used to
quantify EDS have significant limitations. Of particular importance is that no current measure of sleepiness
accounts for the multidimensional nature of the symptom itself, which is a significant barrier in the symptom
science of EDS. This application is grounded in the fundamental philosophy that to understand the biological
bases of excessive sleepiness requires that the phenotype itself be more carefully measured. The use of more
precise objective sleepiness phenotypes will enhance the identification of persons with EDS, as well as the
mapping of these phenotypes to specific brain circuits/pathways. Preliminary data suggest that identification of
patients with EDS is dramatically enhanced using an approach that incorporates multiple measures of
hypersomnolence. In addition, preliminary studies demonstrate that reduced slow wave activity in the
supramarginal gyrus/somatosensory cortex during sleep and thalamostriatal functional connectivity during
wake, are each associated with the subjective complaint of daytime sleepiness. Building on these data, the
next crucial steps in the symptom science of daytime sleepiness are to 1) verify the importance of multimodal
hypersomnolence assessments relative to healthy controls, and 2) to map these neurobiological findings to
specific objective measures of daytime somnolence. Thus, this study will address three Specific Aims targeted
towards these vital areas of inquiry in the symptom science of EDS. First, this investigation will verify whether
a multimodal hypersomnolence assessment, that considers several facets of daytime sleepiness, identifies
persons with unexplained EDS (n=31) compared to age- and sex-matched healthy controls (n=31). Second, it
will identify specific objective measures of sleepiness that are associated with local reductions in slow wave
activity during sleep in the supramarginal gyrus/somatosensory cortex in these study participants. Third, it will
identify specific objective measures of sleepiness that are associated with reduced thalamostriatal functional
connectivity during wake in these same research participants. These achievements will have a sizeable impact
on the symptom science of daytime sleepiness, by enhancing the ability to objectively identify persons with
daytime somnolence, as well as linking measurable sleepiness phenotypes to associated physiological
processes in the brain. In so doing, this project will begin to dissect the various neurobiological pathways
responsible for sleepiness as a symptom, a crucial step in developing personalized medicine approaches to
the care of patients with chronic sleepiness through targeted interve...

## Key facts

- **NIH application ID:** 10022519
- **Project number:** 5R21NR018288-02
- **Recipient organization:** UNIVERSITY OF WISCONSIN-MADISON
- **Principal Investigator:** David T Plante
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $232,563
- **Award type:** 5
- **Project period:** 2019-09-23 → 2022-09-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10022519

## Citation

> US National Institutes of Health, RePORTER application 10022519, The Symptom Science of Excessive Daytime Sleepiness:  A Multidimensional Approach (5R21NR018288-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10022519. Licensed CC0.

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