Medicine of the brain

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MEDICINE/BRAIN ANATOMY

  • Cerebellum
  • The cerebrum
    • the frontal lobe
    • the scalp
    • the temporal lobe with amygdala
    • occipital lobe
  • midbrain
    • thalamus
    • hypothalamus
    • epithalamus
    • endocrine glands: pineal and pituitary glands
  • Brain stem
    • midbrain
    • medulla oblongata
    • bridge of Varolius
    • spinal cord
  • hippocampus
  • meninges
    • hard/firm membrane that protects the brain – Dura matter
    • The arachnoid/middle layer filled with fluid for brain protection
    • Soft membrane located on the surface of the brain – Pia matter
  • GREY AND WHITE SUBSTANCE
  • NERVOUS SYSTEM

1. Cerebellum

It is located in the rear cranial fossa. The gray matter is located on the surface, while the white matter is located in the interior.

FUNCTION:

It coordinates the movement of arms and legs, which are controlled from the center of the brain and under the influence of our will; important for walking and standing.

It is the center for balance; it harmonizes reflex and voluntary movements. Cognitive functions such as attention and language are a part of cerebellum. It is the center for the coordination of movement, planning and balance.

2. The Cerebrum

It occupies most of the cranial cavity. With its ridges and whorls, it is squeezed into a given space. One furrow divides it into the left and right hemisphere.

The cerebrum is divided into four lobes:

  • FRONTAL LOBE – center for personality and planning
  • THE SCALP – center for sense of touch
  • TEMPORAL LOBE – center for sound and sound-image coordination
  • THE OCCIPITAL LOBE – area for vision and visual memory storage

FUNCTIONS OF THE CEREBRUM: center for intelligence/memory, reflections, learning, control of behavior…

3. The AMYGDALA – center of our emotions

Amygdala consists of two interconnected glands, shape and size of almonds, which are found on both sides of our brain near the temples. It keeps memories that cause our fears, so when you are thrown off balance, these glands immediately send an alert to the rest of the brain – heart starts beating rapidly, palms sweat and you are in pre-stress state. The amygdala decides when and what we feel; it is a sensor for positive or negative energy.

It is also responsible for the perception of music. Music information first arrives in the amygdala, which evokes repressed memories related to the same earlier situation and induces emotions accordingly (sadness, relaxation, anxiety …). The amygdala helps us to recognize danger. Without its alarm we would not be able to recognize fears, feelings, people – our own relatives, even the closest ones.

4. Midbrain

Main parts: THALAMUS, HYPOTHALAMUS and EPITHALAMUS

THALAMUS – structure that consists of a number of nuclei (about 35), which have a function to receive impulses, process them and transmit them into the specific sensory areas of the cerebral cortex. It receives impulses from other parts of the thalamus and is associated with areas of the forebrain.

HYPOTHALAMUS – important for regulation of automatic functions related to internal organs. It monitors body temperature, heart rate, blood pressure, eating, drinking, and is involved in the management of emotions and motivation. It is connected to the pituitary gland.

EPITHALAMUS – part of the central nervous system; includes the pineal gland and some minor parts of the brain.

PINEAL and PITUITARY glands also belong to the midbrain.

PITUITARY GLANDS – endocrine glands formed in the shape of a pea, which is connected to the hypothalamus. It secretes hormones that enhance or weaken operations of some glands – it represents the brain for other glands. It affects kidney function, blood pressure and circulation of substances through the body.

It produces important hormones: growth hormone, luteinizing hormone, prolactin, ACT hormone, oxytocin, vasopressin and melanocyte.

EPIPHYSES/pineal gland – organ shaped as pinecone, located exactly on the spot where two hemispheres of the brain are divided.  It is the first gland that develops in our body (5-8 mm). From the light that enters through eyes, about 75% goes into the hypothalamus, and then continues to the pineal gland, which is thus stimulated to secrete hormones into the brain and blood (all other glands derive energy from the body).

Pineal gland is considered as a link between mind and body – it is in charge of human’s universal understanding of life and the world. What the eye can see, the pineal gland understands.

Thanks to the sunlight (the basic food for pineal gland), the energy is distributed to every cell in our body and every organ (liver, kidneys, skin…). It strengthens the immune system, circulatory system, motor skills, sleep and general mood.

The pineal gland secretes the hormone of happiness – SEROTONIN. When night falls, the same hormone is converted into MELATONIN, which is further transmitted into the brain and blood.

Melatonin is responsible for the regeneration of internal organs, skin, hair, genitalia (regulation of the menstrual cycle), for the youthful appearance, quality of rest and sleep.

5. Brain stem

  • MIDBRAIN
  • MEDULLA OBLONGATA
  • BRIDGE OF VAROLIUS
  • SPINAL CORD

MIDBRAIN

The midbrain has a complex structure, with mixed gray and white mass, connecting the fourth to the third ventricle. Many centers of the autonomic nervous system are located in the lower parts of the midbrain.

At the back there are two pairs of nodules:  lower – HEARING, a part of the hearing process and upper – SEEING/VISION, receives information from the retina and cerebral cortex, and are used to adjust the position of the eye.

The function of the middle brain is related to vision, hearing, sleep, excitement, attention and temperature control. It controls muscle tension and maintains posture.

MEDULLA OBLONGATA

It connects the brain and spinal cord, and it is a part of the central nervous system. Its function is important because it contains the centers that manage reflex functions such as breathing, digestive organs operations, blood circulation, blood pressure, coughing, swallowing…  It is often referred to as KNOT OF LIFE because it contains centers that manage important life functions.

BRIDGE OF VAROLIUS

It links the medulla oblongata and midbrain, together forming THE BRAIN STEM.  Functions: maintaining balance and position of the head and body in space – it receives impulses from the receptors to maintain the balance in the middle ear; adjusts mimic, receives stimuli from face skin, ears and teethes. It contains centers for chewing, sucking, as well as centers for defense mechanisms to tears and blinking. It also contains a center that stops spontaneous breathing and thereby regulates the frequency of breathing.

SPINAL CORD

It allows passage of nerve impulses from different parts of the body to the brain and vice versa – movement reflexes, position, scratching and muscle spasms. It performs the functions of the spinal cord.

6. Hippocampus
An area of the brain that is formed as a horseshoe, which helps connecting information from short-term memory to long-term. It is a part of the limbic system associated with emotions and long-term memory.
It participates in the formation, organization and storage of memories. Due to the amount of receptors for GLUCOCORTICOID hormones, it is extremely subject to degenerative processes related mainly to chronic stress, psychiatric diagnosis, but also endocrine disorders (thyroid gland).

7. Meninges

They protect the brain, create supporting framework for the arteries and veins, form venous sinuses and fill the hollow space with fluid. It is the subarachnoid space that is required for normal brain functions.

8. Gray and white matter

They provide a good connection of the center and the periphery of the brain. The brain, the cerebral cortex and spinal cord are built by the gray and white matter.

GRAY MATTER is made of nerve cells and dendrites, and it processes impulses.

WHITE MATTER is built from axons of nerve cells wrapped in myelin sheath – that is the way impulses are transmitted through the white matter in a particular direction. White matter connects brain regions. Loss of memory is associated with white matter of the brain and cognitive impairment.

9. The nervous system

The nervous system is a network of specialized cells that send, transmit and receive information. By processing this information, the nervous system stimulates reactions in other parts of the body. The brain is the center of the nervous system.

Composition: NEURONS (the basis of  nervous system functions) and GLIAL CELLS (they help neuron functions).

Division:

  • peripheral nervous system – consists of nerves
  • Central nervous system – consists of the spinal cord, medulla oblongata and the brain