Which deficiency is not directly associated with any neurological symptoms?

Vitamin D deficiency is primarily associated with issues related to bone health, such as rickets in children and osteomalacia in adults, rather than neurological symptoms. While vitamin D plays a role in numerous physiological functions, its deficiency is not directly linked to neuronal health or cognitive functions in the way that deficiencies in other vitamins, such as B vitamins or vitamin E, can be.

For instance, folate deficiency is well-known for its association with neural tube defects during pregnancy and certain types of anemia that can affect neurological function. Vitamin A deficiency can lead to issues such as night blindness or xerophthalmia and is also implicated in cognitive impairment. Vitamin E deficiency is characterized by neurological symptoms, including ataxia and peripheral neuropathy, due to its role as an antioxidant protecting neuronal membranes from oxidative damage.

By focusing on the specific effects of vitamin D deficiency, it becomes evident that it is not prominently associated with neurological manifestations, distinguishing it from the other vitamins listed.