Occipital lobe

The occipital lobe is important for the human body because it helps us to correctly understand what the eyes are seeing . These lobes have to be very fast to be able to process all the information quickly that our eyes send to the brain. Like the way the temporal lobe makes sense of auditory information, the occipital lobe makes sense of visual information so that we can understand it. If our occipital lobe is damaged or injured, we cannot process visual signals correctly, resulting in visual confusion.

Characteristics of the occipital lobe

The main characteristics of the occipital lobe are:

• It is divided into two different hemispheres and the brain has a right and a left occipital lobe separated by a fissure .
• It has not presented an increase in its size throughout its evolution .
• It is not vulnerable to injury due to its location, however, a serious injury to the brain can have repercussions on the visual and perceptual ability of the body.

Location

The two occipital lobes are located in the human cerebral cortex and are the smallest . They are located in the most posterior part of our skull, while the occipital lobes are also part of the forebrain .

The occipital lobes are supported by the cerebellum . The two lobes are structurally enclosed in their respective cerebral hemispheres by means of the separation of the cerebral fissure . At the front edge there are different convolutions occipital side, which are separated by the lateral occipital groove.

Areas

The areas that we can find in the occipital lobe are the following:

• Primary visual area:  it is located in the most posterior region of the occipital lobe. It has a good definition of the vision map. Lesions in the area produce cortical blindness.
• Secondary visual area: it  is made up of two different regions, the pre-striated cortex that is located around the primary visual area and the inferior temporal that is located in the lower zone of the left lobe. The pre-striated cortex is with memory and association with past visual experiences. The injured cortex produces a lack of recognition.
• Tertiary visual area:  your cells are sensitive to orientation and binocular disparity . Participate in the analysis of the color and shape of visual stimuli.

Features

The occipital lobe is related to the visual cortex , which is the area of ​​the cerebral cortex where the information that comes from the retinas arrives first. This visual cortex is divided into several regions which are classified depending on the level of processing .

The visual cortex is the part of the occipital lobe that is responsible for processing all visual data, so to speak, original, and is responsible for detecting the general patterns that can be found within the information that is obtained through of our eyes. These original data of what is seen are sent to other parts of the occipital lobe, parts that have the function of making a more detailed processing of vision and then send the information that has already been analyzed to other areas of the brain .

It also intervenes in the evaluation of the different distances and the depth of things. It also helps to encode memories, to give them meaning, to develop responses of a linguistic nature and the correct way to respond to the information that surrounds us.

Occipital lobe injuries and diseases

Some of the most common occipital lobe diseases are the following:

• Epilepsy : studies have proven that the occipital lobe is closely related to the onset of epilepsy. In general, there are different visual manifestations such as spots, blindness in a field of vision or blindness. Some people observe flashes of light or sparks. Alterations in the vision of objects or images is also a characteristic sign.
• Hallucinations : Disorders can cause visual hallucinations and different types of illusions. Hallucinations can be caused by lesions in the occipital region or by seizures. Visual illusions happen when objects appear larger or smaller than they really are or have color differences.
• Lesions in the parietal-temporal-occipital association area:  which are capable of causing blindness and pronunciation of words with writing problems.

Lesions that occur in the right occipital lobe cause a loss of vision in both eyes and decreased discrimination of movements.