Effects of Sustained Reading on the Ocular Surface

General inclusion criteria for all subjects will include:

• Ages 50 to 89 years
• Capacity to give informed consent.
• Self-reported literacy (i.e. a "Yes" answer to the question "Have you learned how to read?")

Additional inclusion criteria for the dry eye group will include both of the below:

• A previous diagnosis of dry eye syndrome by an eyecare specialist
• Ocular Surface Disease Index total scoring of 13 or above

Additional inclusion criteria for the Sjögren's syndrome group will include:

- A previous diagnosis of Sjögren's syndrome by an immunology specialist, per ACR criteria 22

Additional inclusion criteria for normal control subjects will include:

• No previous history of dry eye diagnosis
• Ocular Surface Disease Index total scoring of 12 or under
• Total corneal and conjunctival staining score of 0

Exclusion criteria will include:

• A binocular vision below 20/25 (with habitual correction)
• Any ocular surgery within the last 3 months.
• Mental issues, illiteracy, or language problems which might possibly interfere with reading ability
• History of taking or current use of topical prescription anti-inflammatory eyedrops (including, cyclosporine and steroids as well as any glaucoma eyedrops). Subjects who are willing to discontinue their treatment for at least a period of 30 days can be placed on a "wash out period" as per the discretion of the investigator and subject safety, and be eligible at the end of this period, given all other criteria have been met. Otherwise, subjects on these medications will be excluded.