Why does accommodation lag significantly in older adults when switching focus from a distant object to a near object?

💡 Explanation

Accommodation lag in presbyopia happens because the ciliary muscle's ability to contract declines and the lens becomes less elastic. This is due to age-related changes causing stiffening; therefore, the lens cannot change shape rapidly enough for near focus, rather than the viscosity of the vitreous humor or density of cone cells being the main cause.

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