Positioned at the rear of the cerebral cortex, the occipital lobes are the main centres for visual processing, such as the interpretation of colour, shape and distance.
Located within the occipital lobes is the primary visual cortex, a region of the brain that receives visual input from the retina, which is then interpreted in the occipital lobes. The peristriate region of the occipital lobe is involved in visuospatial processing, as well as perception of movement and color.
- Visual perception.
- Color recognition.
- Depth perception.
- Motion detection.
ILLUSTRATION: The visual pathway
Since the occipital lobe is responsible for visual processing, any damage can potentially cause vision problems, such as visual field defects or scotomas.
Damage to one side of the occipital lobe causes homonymous loss of vision with exactly the same 'field cut' in both eyes.
Damage to both sides of the occipital lobes, such as a stroke, may cause cortical blindness, a condition where the eyes still function normally (because its muscles are managed by a different area of the brain), however the visual information received through the eyes is not recognized by the occipital lobe, leaving the person unable to interpret anything in their visual field, rendering them essentially blind.
- Problems with vision.
- Difficulty with identifying colors.
- Inability to recognize words, drawn objects, or movement of objects.
- Difficulty with locating objects in environment.
- Difficulty recognizing familiar faces, loss of visual memory.
- Difficulty with reading and writing.
- Visual illusions and hallucinations.
