Käbinäärme

Käbinäärme, also known as the pineal gland, is a small endocrine gland in the epithalamus of the vertebrate brain. It produces melatonin, a hormone that affects the regulation of sleep-wake cycles. The gland is shaped roughly like a pine cone, hence its name. It is located in the midline of the brain, between the two hemispheres, and is often referred to as the "third eye" in various spiritual and mystical traditions due to its supposed connection to higher consciousness and intuition.

The primary function of the pineal gland is the production and secretion of melatonin. This hormone is synthesized from serotonin and its release is regulated by light. In darkness, melatonin levels rise, signaling the body to prepare for sleep. As light increases, melatonin production decreases, promoting wakefulness. This circadian rhythm is crucial for regulating various bodily functions, including sleep patterns, body temperature, and hormone release.

While its role in melatonin production is well-established, the pineal gland has been the subject of much speculation and research beyond its endocrine functions. Ancient philosophies and esoteric traditions have often attributed mystical or spiritual significance to the pineal gland, viewing it as a source of psychic abilities or a gateway to other dimensions. Scientific research continues to explore the full range of the pineal gland's functions and its potential role in various neurological and psychological processes.