Refractive error, cognitive demand and nearwork-induced transient myopia.

Area of Science:

• Ophthalmology
• Vision Science
• Cognitive Neuroscience

Background:

• Sustained near work is linked to myopia development.
• The role of cognitive effort in myopia progression is less understood.
• Near-work induced transient myopia (NITM) affects accommodative function.

Purpose of the Study:

• To investigate the influence of cognitive effort on near-work induced transient myopia (NITM).
• To compare accommodative responses in early-onset myopes (EOMs), late-onset myopes (LOMs), and emmetropes (EMMs) under varying cognitive loads.

Main Methods:

• Monocular accommodation was measured using autorefraction during a 5-minute arithmetic task.
• Participants (EOMs, LOMs, EMMs) engaged in active or passive cognitive tasks at near, followed by a far viewing task.
• Cognitive conditions (active/passive) were varied and randomly allocated.

Main Results:

• Late-onset myopes (LOMs) exhibited less accurate accommodation during the near task compared to EOMs and emmetropes.
• Early-onset myopes (EOMs) showed significant NITM compared to LOMs and emmetropes during the far task.
• NITM persistence in EOMs was highest when active cognition at near was followed by passive cognition at far.

Conclusions:

• EOMs and LOMs are more susceptible to NITM than emmetropes, with sustained near vision impairing far vision accommodative accuracy.
• Marked NITM in EOMs may relate to crystalline lens thinning.
• Cognitive demand must be considered when assessing phenomena like NITM.