Pruritis is a common symptom in patients with atopic dermatitis and psoriasis. Patients with atopic dermatitis and psoriasis often report pruritis-associated sleep impairments and scratching behaviors during nighttime and the negative impact on their quality of life. However, nocturnal scratch behavior and sleep impairment are poorly understood due to the difficulties in quantifying these symptoms in patients' daily lives. This study deploys multiple technologies (polysomnography, video capture, wrist sensors, clinician-reported outcomes, and patient-reported outcomes) to develop and validate a wrist-based solution to quantify nocturnal scratch.

Inclusion criteria for participants with atopic dermatitis:

• At least 14 years old
• Less than 70 years old
• Clinical diagnosis of Atopic Dermatitis
• Peak Pruritis NRS score > 1

Inclusion criteria for participants with psoriasis:

• At least 18 years old
• Less than 70 years old
• Clinical diagnosis of plaque psoriasis
• At least a peak pruritis PNRS of 4
• Itch is caused by psoriasis, as determined by clinician

Exclusion Criteria:

• Non-Atopic Dermatitis or Psoriasis-related sleep disorder (e.g., diagnosed sleep apnea, restless leg syndrome etc...)
• Movement disorder
• Flare or infection on the wrist
• Infected atopic dermatitis or psoriasis lesions
• Pregnant or lactating women
• Shift workers or participants with jetlag
• Current diagnosis of depression

Male and female subjects, aged 14-70 years old, with active atopic dermatitis or psoriasis