Which part of brain involves in emotions and behavior and what is pineal gland | Biology of Emotion | psychology | pineal gland

                                                     Biology of Emotion

The limbic system, the autonomic nervous system, and the functional reactivation system in sensory processing. Emotions can be defined in terms of biological and sensory factors. The limbic system, the autonomic nervous system, and the regenerative system all combine to assist the body in trying and functioning the senses.

  Key points: 

• The limbic system, the autonomic nervous system, and the functional repetitive system all contribute to the functioning of the emotional body.
•  The limbic system classifies a person's emotional experiences as positive or negative emotions. Neurochemicals such as dopamine, noradrenaline, and serotonin are important components of the limbic system.
•  The autonomic nervous system, along with the hypothalamus, regulates heart rate, blood pressure, respiration, and arousal in response to emotional signals.
•  When activated, the sympathetic nervous system prepares the body for emergency actions by controlling the endocrine system glands. On the other hand, the parasympathetic nervous system is active when the body is relaxed or at rest and helps the body retain energy for future use.
•  The functional retrieval system is believed to initiate the stimulation of the cortex and maintain its arousal so that the details of the nerves and senses can be interpreted with great success. 

The Limbic System:

The limbic system is the area of the brain most affected emotionally and memory. Its structures include the hypothalamus, thalamus, amygdala, and hippocampus. The hypothalamus plays a role in the functioning of the sensory nervous system, which is part of any emotional response. The thalamus acts as a central nervous system; signals of its project in the amygdala and in the higher cortical regions of continued function. The amygdala is involved in the processing of emotional information and sends that information to cortical structures. The hippocampus combines emotional information with perception. 

Other components of the limbic system include olfactory bulbs, anterior nuclei, fornix, column of fornix, mammillary body, septum pellucidum, habenular commissure, cingate gyrus, parahippocampal gyrus, limbic cortex, and limbic midbrain areas. 

The processes of the limbic system control our physical and emotional responses to environmental issues. This program distinguishes the emotional experience as a positive or negative attitude. Based on this list, neurochemicals such as dopamine, noradrenaline, and serotonin increase or decrease, causing brain activity to change and lead to changes in body movements, physical activity, and appearance.

 Key Terms:

1	Homeostasis	Body balance, where biological conditions (such as body temperature) are maintained at appropriate levels
2	Cerebral cortex	The gray, folded, outer layer of the cerebrum is responsible for higher brain processes such as hearing, voluntary muscle movement, thinking, reasoning, and memory.
3	Amygdala	Part of the brain located in the medial temporal lobe. It is believed to play a significant role in the emotions of both animals and humans, especially in the formation of fearful memories.
4	Hippocampus	Part of the limbic system, located in the temporal lobe of the brain and consisting mainly of gray matter. It plays a role in memory and emotions.
5	Emotion	A complex psychophysiological experience of the human mind state as it combines biochemical (internal) and environmental (external) influences.

Pineal Gland

The pineal gland, also called the conarium, epiphysis cerebri, pineal organ, or pineal body, is an endocrine gland found in the vertebrates that are the source of melatonin, a hormone found in tryptophan that plays a major role. in controlling circadian rhythm (approximately 24- hour cycle of biological activities associated with natural times of light and darkness).

v Pineal hunger:

The human pineal gland is located behind the third ventricle of the brain in the middle (between the two hemispheres of the brain) of the brain.

Pineal gland has long been a complex structure. Even in the early 21st century, when sophisticated molecular technology became available for biological research, the basic components of this gland - including the effects of its main hormone, melatonin - remained elusive.

 

v Left cerebral hemisphere of the human brain:

       Medial view of the left hemisphere of the human brain.

 

 Human Endocrine System

Major glands of the human endocrine system. The hypothalamus stimulates the pituitary gland and has an effect on diet, weight control, diet and balance, thirst, body temperature, and sleep cycle. Pituitary hormones stimulate growth, egg and sperm growth, milk production, and the release of hormones by other hormones. The pineal gland can play a major role in sexual maturation and circadian rhythm. Thyroid hormones regulate body tissue levels, stimulate heart muscle contraction, and are essential for normal growth and development of the brain before birth and in childhood. Parathyroid hormone regulates the levels of calcium, phosphorus, and magnesium. The adrenal glands regulate retention of salt and water, a certain immune response, and blood pressure. The Langerhans Islands control blood sugar levels. Eggs and testes produce hormones that regulate the reproductive system and produce male and female sexual characteristics.

 Anatomy of the pineal gland:

The pineal gland grows from the roof of the diencephalon, part of the brain, and is located behind the third cerebral ventricle in the midline of the brain (between the two cerebral hemispheres). Its name is derived from its shape, similar to that of the pinecone (Latin pinea). In adults it is about 0.8 cm (0.3 inches) tall and weighs about 0.1 grams (0.004 ounce).

 Pineal hormones:

Both melatonin and its predecessor, serotonin, which are chemically derived from the alkaloid drug tryptamine, are synthesized in the pineal gland. Along with other brain sites, the pineal gland can also produce neurosteroids. Dimethyltryptamine (DMT), a hallucinogenic compound present in the Amazonia botanical drink ayahuasca (produced by Banisteriopsis caapi, a South American forest vine), is similar to chemicals such as melatonin and serotonin and is considered as a sequence in human blood. Although suspected to be produced by the pineal gland, DMT has not been consistently detected in human pineal microdialysates (extracted from pineal extracts), and evidence that its biosynthesis is regulated in the mammalian pineal gland. Thus, although the conclusion of the 17th-century French philosopher René Descartes that the pine need is the soul's lifespan endured as a matter of history, there is no evidence to support the view that the secrets of the pineal gland play a major role in understanding.

In addition to the pineal gland, melatonin is also absorbed into the spinal retina, where it transmits information about natural light through local receptors MT1 and MT2, and to other specific tissues, such as the intestinal tract and skin. In a step that limits the overall rate of melatonin biosynthesis, an enzyme called serotonin N-acetyltransferase (AANAT) promotes the conversion of serotonin into N-acetylserotonin. The combination was then supplemented with melatonin by acetylserotonin O-methyltransferase (ASMT). The increase in melatonin concentration cycle that occurs and is maintained after sunset and darkness is associated with the activity of AANAT during dark times. Melatonin concentration is also higher in cerebrospinal fluid (CSF) of the third ventricle of the brain than CSF of the fourth ventricle or blood. That suggests that melatonin is also secreted directly into the CSF, where it may have more direct and perhaps more direct effects on the central nervous system.

In some types of pineal cells are sensitive to air. In humans and advanced mammals the “photoendocrine system” — made up of the retina, the upper nucleus of the hypothalamus, and the noradrenergic sensory fibers (neurons that respond to neurotransmitter and repinephrine) end up in the pineal gland circadian which regulates pineal melatonin secretion. Unlike many other endocrine hormones, human melatonin levels vary widely, and serum melatonin levels drop dramatically in childhood, as there is little or no growth in pineal gland after one year of age.

 Pineal physiology and pathophysiology:

The level of melatonin circulation in the vertebrates is found in the secretion of melatonin pine, and their size teaches the brain regions about the dark cycles of natural light and the time of year, as a result of changes in the melatonin plain at night. These indicators, in turn, help to incorporate sleep function (created by darkness) and reproductive cycle events (enhanced by more seasonal lighting). In birds, mice, and occasional mammals, pinealectomy (removal of the pineal gland) disrupts fertility. In those types there are indications that melatonin stimulates the release of gonadotropin-inhibitory hormone, which also leads to suppression of gonadotropin (hormones that work in the ovaries or testicles), which can explain the disruptive effects on production.

In humans both puberty and delayed puberty have been associated with pineal gland and cysts. However, the pathogenesis that leads to such conditions is unclear, and both mechanical and hormonal factors may be involved. A positive relationship between melatonin blockade and other hormones has been reported, although no pure melatonin tissue has ever been detected. Indeed, unlike other endocrine glands, such as the pituitary, adrenal, and thyroid, there is no pineal hormone deficiency or hormone-excess syndromes.

Lack of pineal gland disease including hormone deficiency or hormonal overdose has been a barrier to the investigation of the role of starvation. Such roles include the possibility that melatonin secretion is an important factor in the formation and maintenance of nighttime sleep, as suggested by previous studies in night workers. Little is known about the genetic variation in melatonin levels and the relationship between those types of sleep disorders and other circulatory disorders. However, melatonin administration is associated with many and varied effects, including immune responses, cellular modification, and protection from oxidative stress. That comment has revived research into the therapeutic potential of melatonin and its analogues, as some melatonin receptor agonists (e.g., Tasimelteon) have been approved for the treatment of certain sleep-related disorders.

REFRINCE

https://courses.lumenlearning.com/boundless-psychology/chapter/biology-of-emotion/

Emerson, C. H. (2020, May 26). Pineal gland. Encyclopedia Britannica. https://www.britannica.com/science/pineal-gland