The document describes several key structures and regions of the central nervous system, including the brain and cerebellum. It discusses the gyri and sulci that fold the surface of the brain into functional centers. Specific sulci mentioned include the longitudinal fissure separating the hemispheres, the central sulcus defining motor and sensory cortex, and the lateral sulcus separating the temporal and parietal lobes. Key gyri include the precentral gyrus controlling movement and the superior temporal gyrus involved in communication. Deep brain structures are also outlined, such as the pineal gland regulating circadian rhythms and the cerebral peduncles connecting the brainstem to the cerebrum.

1. CENTRAL NERVOUS SYSTEM

10. Gyri and Sulci of the Brain
The surface of the brain, known as the cerebral cortex, is very uneven,
characterized by a distinctive pattern of folds or bumps, known as gyri
(singular: gyrus), and grooves, known as sulci (singular: sulcus). These gyri
and sulci form important landmarks that allow us to separate the brain into
functional centers.
Brain Sulci or Fissures
Longitudinal fissure
The longitudinal fissure is a deep furrow located within the center of the
brain, separating the left and right hemispheres. Within this fissure is the
corpus callosum, which is a bundle of nerve fiberes that connects the left and
right hemispheres of the brain in order to send visual, auditory,
and somatosensory information between each half.

12. Central sulcus
The central sulcus, also known as the sulcus of Rolando, separates the parietal
and frontal lobes. This is an essential sulcus because it defines the boundary
between primary motor cortex and primary somatosensory cortex as well as
between the parietal and frontal lobes.
Parieto-occipital sulcus
The parieto-occipital sulcus is a deep groove which separates the parietal and
occipital lobes of the brain
Lateral sulcus
The lateral sulcus is a deep groove which separates the parietal and temporal
lobes. This is also known as the Sylvian sulcus and begins near the forebrain,
extending to the lateral surface of the brain

14. Brain Gyri
Precentral gyrus
The precentral gyrus is a part of the brain’s cortex responsible for executing voluntary
movements, located in the most posterior position of the frontal lobe, outlining the
temporal lobes.

15. Cingulate gyrus
The cingulate gyrus is a component of the limbic system, consisting of a
curved fold which covers the corpus callosum (a bundle of nerve fiberes
which connects the right and left cerebral hemispheres).
The cingulate gyrus has a role in the processing of emotions and the
regulation of behavior. As a result, damage to this area can result in
emotional and behavioral disorders. This region is also involved in regulating
autonomic motor function

16. Superior temporal gyrus
The superior temporal gyrus forms the most superior part of the temporal lobe,
and has a role in both verbal and non-verbal communication
The superior temporal gyrus is an area which contains the auditory cortex, which
is responsible for the processing of sounds.

32. Pineal gland, also called the pineal body or epiphysis cerebri, is a tiny gland in your
brain that's located beneath the back part of the corpus callosum. It's a part of your
endocrine system and secretes the hormone melatonin.
The pineal gland is key to the body's internal clock because it regulates the body's
circadian rhythms. Circadian rhythms are the daily rhythms of the body, including signals
that make someone feel tired, sleep, wake up, and feel alert around the same time each
day.

35. CEREBRAL PEDUNCLE - DEFINITION
A large bundle of neurons that resembles a large stalk (the Latin pedunculus means
"footstalk") and stretches from the cerebrum to the pons. There are two cerebral
peduncles, one on each side of the brainstem. The cerebral peduncles contain
important descending tracts like the corticospinal tract and corticobulbar tracts.

37. Tegmentum Location: Between the cerebral aqueduct and the pars
compacta of the substantia nigra
Function: Coordination of movement, pain processing,
alertness
Tectum Location: Midbrain, posterior to the cerebral aqueduct
of Sylvius.
Function: Auditory and visual processing
The cerebral crus (crus cerebri) is the anterior portion of the cerebral
peduncle which contains the motor tracts, travelling from the cerebral
cortex to the pons and spine

41. The cerebellum, which stands for “little brain”, is a structure of the central
nervous system.
The cerebellum is located at the back of the brain, immediately inferior to
the occipital and temporal lobes, and within the posterior cranial fossa. It
lies at the same level of and posterior to the pons, from which it is
separated by the fourth ventricle.
Cerebellum