The pineal gland is the gland often referred to as "brain sand." This isn't because the entire gland is made of sand, but because it contains small, calcium-based concretions called corpora arenacea, also known as acervuli or brain sand. These calcified structures are visible on x-rays and increase in number and size with age.
What are Corpora Arenacea?
Corpora arenacea, or brain sand, are small, calcified structures found within the pineal gland. Their exact function remains unclear, but they are a common finding, especially in older individuals. These concretions are composed of a complex mixture of polycrystalline material and are a hallmark of the pineal gland's aging process.
- Increased calcification with age: The amount of brain sand in the pineal gland generally increases as a person ages. This makes them a useful landmark in certain medical imaging techniques.
- Visible on X-rays: Their high calcium content makes corpora arenacea readily detectable using radiographic imaging methods.
- Multiple names: These structures are known by various names including brain sand, acervuli, psammoma bodies, and corpora arenacea.
The pineal gland itself is a small endocrine gland located in the brain's posterior aspect. Its primary known function is the production of melatonin, a hormone crucial for regulating sleep-wake cycles (circadian rhythms). However, the presence and significance of corpora arenacea within the pineal gland remain areas of ongoing research.
