The posterior cerebral artery (PCA) is a major blood vessel in the brain that supplies oxygenated blood to the posterior part of the cerebral hemispheres. It primarily nourishes areas responsible for vision, including the occipital lobe and parts of the temporal lobe. The PCA branches off from the basilar artery and plays a crucial role in maintaining the health of these brain regions. In addition to supplying blood to the visual areas, the PCA also provides blood to the thalamus and the hippocampus, which are important for sensory processing and memory, respectively. Any blockage or damage to the PCA can lead to significant neurological deficits, including visual disturbances and memory issues.