Brain As Central Nervous System – This time I will share high school science material about the central nervous system.

Brain as Central Nervous System

BRAIN (cerebrum)

The brain is the front part of the central nervous system that undergoes changes and enlargement. This section is protected by 3 membranes of the brain called the meninges (dura mater, arachnoid, and pia mater) and is located in the cranial cavity.

Brain parts:

Cerebral hemisphere

The two cerebral hemispheres, which make up the largest part of the brain, are separated by a deep longitudinal cerebral fissure. The surface of the cerebral hemispheres contains grooves or trenches known as fissures and sulci. The part of the brain that lies between these grooves is called the convolutions or gyrus. The lateral cerebral fissure (fissure of Sylvii) separates the temporal lobe from the frontal lobe.

The main parts of the cerebrum:

Frontal Lobe : Here lies the involuntary control center of the skeletal muscles on the opposite side of the body, and nerve impulses travel along the axons of nerve cells in the corticobulbar and corticospinal tracts to the cerebrospinal nerve nuclei. Irritative lesions to the area may cause seizures, which begin with focal seizures and then extend to include large muscle groups, impaired consciousness and convulsive weakness or paralysis. Destructive lesion of the area will produce contralateral paresis of the corresponding muscle.

Parietal Lobe : In the postcentral gyrus lies the primary sensory projection cortex for the reception of general sensations originating from the thalamic radiation and carrying sensibility from the skin, muscles, joints and tendons on the opposite side of the body.

Occipital Lobe : In this lobe is located the visual receptive cortex (vision)

Temporal Lobe : In the transverse temporal gyrus lies the center of the reception of auditory stimuli

Insula : This insula is embedded in the lateral cerebral fissure and can be demonstrated by separating the upper and lower margins of the fissure.

Rhinecephalon : Includes parts related to olfactory perception (olfactory / smell)


This section includes the thalamus with the geniculate body, epithalamus, subthalamus and hypothalamus. The thalamus is a decisive structure for the perception of several types of sensations. The hypothalamus is located ventral to the thalamus and forms the floor and lateral inferior wall of the third ventricle. Damage to the hypothalamic region can produce a variety of symptoms including diabetes insipidus, obesity, sexual dystrophy, somnolence, loss of sex drive and loss of temperature control.


It is a short part of the brain that lies between the pons and the cerebral hemispheres. On the sides are the nuclei of the oculomotor (n.III) and trochlear (n.IV) cranial nerves, which play a role in eye movement.


Located ventral to the cerebellum and anterior to the medulla. In this pons are located the nuclei of the trigeminal (nV), abducens (n.VI), facial (n.VII), and vestibular-cochlear (n.VIII) cranial nerves. Lesions in the brainstem area can cause symptoms that can be attributed to the involvement of motor and sensory pathways that pass through the lesion, especially to the involvement of cranial nerve nuclei within the lesion area.


It is a pyramid-shaped part of the brainstem between the spinal cord and the pons. In the medulla oblongata, the glossopharyngeal (n.IX), vagus (nX), accessory (n.XI) and hypoglossal (n.XII) cranial nerve nuclei are located.


Located in the posterior fossa of the skull behind the pons and medulla, it is separated from the cerebrum superiorly by an extension of the dura mater, the tentorium cerebeli. The functions of the cerebellum include maintaining body position, controlling the antigravity muscles of the body, and braking on voluntary movements, especially movements that require supervision and stopping as well as fine movements of the hands.

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