Lets learn about the brain.
The central nervous system consists of the brain and spinal cord.
The outer portion of the brain is called the cerebrum.
The cerebrum contains a number of structures.
The folds on the surface of the cerebrum are called gyri.
The grooves are called sulci and the deep grooves are called fissures.
Deep to the cerebrum is the diencephalon which contains the thalamus and hypothalamus.
Just below the diencephalon is the brain stem which consists of 3 parts.
The superior portion is called the midbrain.
Just below the midbrain is the pons and below the pons is the medulla oblongata.
The cerebellum is on the posterior inferior aspect of the brain.
The cerebrum is divided into lobes.
The frontal lobe processes concentration, planning and problem solving along with motor
information.
The pre-central gyrus on the frontal lobe is known as the primary motor area.
The central sulcus divides the frontal and parietal lobes.
The post-central gyrus of the parietal lobe is known as the primary sensory area .
The occipital lobe is in the back of the cerebrum and processes visual information.
The temporal lobe processes auditory information.
The lateral sulcus divides the temporal lobe from the other lobes.
The cerebellum processes fine motor movements, coordination and proprioception which is the
position of joints in space.
The insula lies deep in the lateral sulcus and processes information for consciousness,
motor control, homeostasis and emotions.
The cerebrum is divided into 2 hemispheres by the longitudinal fissure.
This is a mid-sagittal section of the brain.
We can see the corpus callosum, a white matter bridge that unites both hemispheres of the
cerebrum.
The diencephalon is inferior to the corpus callosum and contains the thalamus and hypothalamus.
The thalamus relays sensory information to the cerebrum.
It is also involved in emotions.
The hypothalamus helps to regulate pituitary gland secretions.
It also regulates body temperature, thirst, hunger, sexual drive and is involved along
with the reticular formation in regulating sleep.
The pituitary gland is connected to the hypothalamus via the infundibulum and sits in the sella
turcica of the sphenoid bone.
The pineal gland is located in the posterior portion of the diencephalon and secretes the
hormone melatonin which helps to regulate sleep.
Lets look at the brainstem in more detail.
The midbrain contains the superior and inferior colliculi which are involved in controlling
movements of the head toward stimuli as well as hearing.
The pons contains respiratory centers and is involved in regulating sleep.
The medulla oblongata helps to regulate heart rate, respiration, swallowing vomiting and
blood vessel diameter.
Limbic system processes emotions.
It Includes cingulate gyrus, parahippocampal gyrus, hippocampus, amygdaloid body, mamillary
body, parts of thalamus and hypothalamus.
Cerebrospinal fluid (CSF) is a clear fluid that circulates inside and around the brain.
It functions as a Shock absorber, contains immune system cells, and helps to regulate
cerebral blood flow.
CSF is Produced by choroid plexus (vascular structure).
There are 4 hollow areas or ventricles inside of the brain.
These include 2 lateral ventricles, a third and fourth ventricle.
The Lateral ventricles connected to third ventricle via interventricular foramen
The third ventricle connects to the fourth via the cerebral aqueduct.
The covering of the brain is called the meniges.
There are 3 layers to the meninges.
The outer tough fibrous layer is called the dura mater.
On the inside of the dura mater is the arachnoid mater.
The thin pia mater contacts the brain.
There is a space between the arachnoid and pia mater called the subarachnoid space.
This space is filled with CSF.
A vascular structure called the choroid plexus produces CSF.
Arachnoid granulations absorb it.
About 500 ml of CSF is produced daily.
Here are a couple of special areas in the brain.
Broca's area is involved in language production and comprehension.
Wernicke's area is involved in speech recognition
We hope you have learned something about the brain and see you next time.