The National Institutes of Health (NIH) is offering a funding opportunity titled "Mechanistic Studies to Investigate the Interrelationship Between Sleep and/or Circadian Rhythms and Substance Use Disorders" under the R01 Research Project Grant mechanism. This initiative aims to support basic experimental studies involving human participants to explore the connections between sleep patterns, circadian dysregulation, and substance use disorders (SUDs), with the goal of identifying new therapeutic and preventative strategies. The total funding commitment for this opportunity is $2 million for fiscal year 2025, with approximately three to five awards anticipated, each capped at $300,000 per year. Applications are due by October 30, 2024, and interested parties can contact NIH Grants Information at grantsinfo@nih.gov for further inquiries.