A Non-Drug Study Detecting And Quantifying Nocturnal Scratch Behaviors From Wrist Actigraphy Data In Adult Healthy Volunteers And Participants With Atopic Dermatitis (AD)

Inclusion Criteria: * Volunteers in general good health with no diagnosis of AD or any other dermatologic disorder that interferes with study assessments. * For subjects with AD: * Chronic AD with onset of symptoms at least 1 year prior to Day 1 and participant meets American Academy of Dermatology (AAD) criteria. * Participant meets all of the following disease activity criteria: * For AD subjects with high disease activity (AD-High): * Pruritus over the last 7 days (numerical rating scale 7-Day version \[NRS-7\]) \>= 4 at the Screening and Day 1 visits. * At least one of the following: * Eczema Area and Severity Index (EASI) score \> 7 at the Screening and Day 1 visits; OR * Validated Investigator Global Assessment for AD (vIGA-AD) score \>= 3 at the Screening and Day 1 visits; * For AD subjects with low disease activity (AD-Low): * Pruritus over the last 7 days (NRS-7) \>= 2 at the Screening and Day 1 visits. * Does not meet AD-High criteria as described. * Satisfy at least one of the following: * EASI score \>= 3 at the Screening and Day 1 visits OR * vIGA-AD score \>= 1 at the Screening and Day 1 visits. Exclusion Criteria: * Significant eczema on wrists where devices will be worn that, in the opinion of the participant or investigator would likely lead to non-compliance. * Interference (e.g., hairstyle) with the ability of Dreem 2 headband to collect sensor data. * Unstable medical disorder or other condition that in the investigator's opinion may interfere with study procedures or study objectives.