The lateral ventricles are part of the ventricular system

Ventricular system

The ventricular system is a set of structures containing cerebrospinal fluid in the brain. It is continuous with the central canal of the spinal cord.-Components:The system comprises four ventricles:* right and left lateral ventricles* third ventricle...

 of the brain

Brain

The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

. Classified as part of the telencephalon

Telencephalon

The cerebrum or telencephalon, together with the diencephalon, constitutes the forebrain. The cerebrum is the most anterior region of the vertebrate central nervous system. Telencephalon refers to the embryonic structure, from which the mature cerebrum develops...

, they are the largest of the ventricles.

The lateral ventricles connect to the central third ventricle

Third ventricle

The third ventricle is one of four connected fluid-filled cavities comprising the ventricular system within the human brain. It is a median cleft between the two thalami, and is filled with cerebrospinal fluid ....

 through the interventricular foramen of Monro.

Clinical significance

The volume of the lateral ventricles are known to increase with age. They are also enlarged in a number of neurological conditions and are on average larger in patients with schizophrenia

Schizophrenia

Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...

, bipolar disorder

Bipolar disorder

Bipolar disorder or bipolar affective disorder, historically known as manic–depressive disorder, is a psychiatric diagnosis that describes a category of mood disorders defined by the presence of one or more episodes of abnormally elevated energy levels, cognition, and mood with or without one or...

, major depressive disorder  and Alzheimer's disease

Alzheimer's disease

Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...

.

Divisions

Each lateral ventricle has three horns:

• the anterior or frontal horn extends into the frontal lobe
  Frontal lobe
  The frontal lobe is an area in the brain of humans and other mammals, located at the front of each cerebral hemisphere and positioned anterior to the parietal lobe and superior and anterior to the temporal lobes...
  
  
• the posterior or occipital horn
  Posterior horn of lateral ventricle
  The posterior horn of the lateral ventricle passes into the occipital lobe, its direction being backward and lateralward, and then medialward....
  
   into the occipital lobe
  Occipital lobe
  The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area 17, commonly called V1...
  
  
• the inferior or temporal horn into the temporal lobe
  Temporal lobe
  The temporal lobe is a region of the cerebral cortex that is located beneath the Sylvian fissure on both cerebral hemispheres of the mammalian brain....
  
  

The body of the lateral ventricle is the central portion, just posterior to the frontal horn. The trigone of the lateral ventricle is a triangular area defined by the temporal horn inferiorly, the occipital horn posteriorly, and the body of the lateral ventricle anteriorly. The cella media is the central part of the lateral ventricle. Ependyma

Ependyma

Ependyma is the thin epithelial membrane lining the ventricular system of the brain and the spinal cord. Ependyma is one of the four types of neuroglia in the central nervous system. It is involved in the production of cerebrospinal fluid ....

 cover the inside of the lateral ventricles and are epithelial cells.

Development

The lateral ventricles, similarly to other parts of the ventricular system of the brain, develop from the central canal of the neural tube. Specifically, the lateral ventricles originate from the portion of the tube that is present in the developing prosencephalon, and subsequently in the developing telencephalon. During the first trimester of pregnancy central canal expands into lateral, third and fourth ventricles, connected by thinner channels. In lateral ventricles specialized areas- choroid plexuses appear, which produce cerebrospinal fluid

Cerebrospinal fluid

Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...

. If its production is bigger then resorption or its circulation is blocked- the enlargement of the ventricles may appear and cause a hydrocephalus

Hydrocephalus

Hydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...

. Fetal lateral ventricles may be diagnosed using linear or planar measurements.