Which of the following does NOT happen during accommodation?

During accommodation, when the eye focuses on a near object, the ciliary muscle contracts, releasing tension on the zonules that hold the lens in place. This relaxation decreases the zonular tension, allowing the lens to become more rounded and increase its refractive power, which is essential for near vision.

The movement of the posterior pole of the lens backward is also a characteristic of accommodation; as the lens becomes more rounded, the shape changes cause it to bulge forward, resulting in a slight shift of the posterior pole.

Similarly, the anterior chamber depth decreases during accommodation because the lens increases in curvature and volume as it bulges, consequently pushing the iris forward against the cornea, leading to a shallower anterior chamber.

Given this context, the statement regarding lens zonule tension increasing is not accurate during accommodation. In fact, it is the opposite that occurs; the zonule tension decreases, facilitating the rounded shape of the lens necessary for focusing on near objects.