The Pineal Gland

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The Pineal Gland

The pineal gland is a pea-shaped organ present deep in the centre of the brain between the two hemispheres. The pineal gland contains mainly pinealocytes, that produce the melatonin hormone.

The Pineal Gland

The pineal gland keeps a measure of the body’s internal clock as it regulates the body’s circadian rhythms. Circadian rhythms are the daily rhythms of the body which includes signals that modulate one’s tired, sleep, wake up, and feel alert throughout the day. The hormone melatonin is secreted by the pineal gland which regulates circadian rhythms and the secretion depends upon the amount of light one is exposed to. So its natural production is more during sleeping hours when one is not exposed to light. The normal secretion of this hormone helps for better sleep.

The sleep cycle is very important to maintain good mental health conditions. Lack of sleep may lead to many disorders and can also hamper one’s mental state causing problems like depression. One of the known disorder called seasonal affective disorder which is a form of depression that affects a person’s mood and tends to occur when light levels are low. This may be due to changes in melatonin secretion. However, there is no such strong evidence to prove the fact. But the fact of deprived of sleep can actually lead to various health problems, one of which is obesity also.

Other Functions

  •  It inhibits the reproductive function
  • Protects neural tissue from free radicals
  • The dysfunction of the pineal gland can also hamper pituitary gland to secrete the major hormones which are required for testes and ovaries, may lead to disturbance in the menstruation cycle.
  • The secretion of melatonin is reduced proportionally with age, hence there is a reduction of sleep with growing age.