Parasympathetic innervation of which muscles results in lens accommodation in the eye?

• A. Dilator pupillae muscles
• B. Ciliary muscles
• C. Lateral rectus muscles
• D. Superior rectus muscles

Answer: (B)

Verified step by step guidance

1. Understand the concept of lens accommodation: Lens accommodation refers to the process by which the eye changes the shape of the lens to focus on objects at different distances. This is controlled by the parasympathetic nervous system.
2. Identify the role of the ciliary muscles: The ciliary muscles are responsible for changing the shape of the lens during accommodation. When these muscles contract, the lens becomes more rounded, allowing the eye to focus on nearby objects.
3. Clarify the role of parasympathetic innervation: Parasympathetic innervation stimulates the contraction of the ciliary muscles, enabling lens accommodation. This is mediated by the oculomotor nerve (cranial nerve III).
4. Differentiate the other muscles listed: The dilator pupillae muscles are involved in pupil dilation and are controlled by the sympathetic nervous system, not parasympathetic. The lateral rectus and superior rectus muscles are extraocular muscles responsible for eye movement, not lens accommodation.
5. Conclude that the ciliary muscles are the correct answer: Based on the function of the ciliary muscles and their parasympathetic innervation, they are the muscles responsible for lens accommodation in the eye.