Anatomical Overview of the Arteries of the Human Brain

• Frontal, Parietal, and Temporal branches: These supply the respective lobes on the lateral surface.
• Precentral branch: Supplies the motor areas.
• Lateral orbitofrontal branches: Supply the lower lateral aspects of the frontal lobe.

Connecting Vessels

To ensure redundant blood flow (a safety mechanism known as the Circle of Willis), several communicating arteries link the systems. The Anterior Communicating Artery connects the two anterior cerebral arteries near the midline. Additionally, the Posterior Communicating Artery serves as a vital link between the anterior (carotid) and posterior (vertebrobasilar) systems.

Exam Tip: If a question asks which artery supplies the lateral surface of the brain and is most commonly involved in strokes affecting speech or movement, the answer is almost always the Middle Cerebral Artery (MCA).

The Vertebrobasilar System

While the carotid system handles the "front" of the brain, the Vertebrobasilar system is responsible for the posterior and inferior regions, including the brainstem and cerebellum.

Vertebral and Basilar Arteries

The Vertebral Arteries enter the cranium from the bottom, ascending to merge and form the single, large Basilar Artery. The Basilar artery provides essential blood to the brainstem via pontine branches and extends upward to give rise to the Posterior Cerebral Arteries (PCA).

Posterior Cerebral and Cerebellar Arteries

The PCA is the major vessel of the posterior section, supplying the occipital lobe and parts of the temporal lobe. Furthermore, the system provides specialized blood to the cerebellum through the Cerebellar Arteries:

• Superior Cerebellar Artery.
• Anterior Inferior Cerebellar Artery (AICA).
• Posterior Inferior Cerebellar Artery (PICA).

Deep Brain Perfusion and Specialized Structures

Beyond the major cortical vessels, the brain relies on "penetrating" arteries that dive deep into the tissue to reach vital subcortical structures.

The Lenticulostriate and Striate Arteries

One of the most critical groups of vessels is the Lenticulostriate Arteries (also known as anterolateral central arteries). These small, thin-walled vessels branch off the MCA to supply the Corpus Striatum. The corpus striatum is a key component of the basal ganglia and includes:

• Caudate Nucleus.
• Lentiform Nucleus.

These arteries also supply the Internal Capsule (a major white matter pathway) and the Insula (the cortex located deep within the lateral sulcus). Another vital deep vessel is the Long Striate Artery, frequently referred to as the Recurrent Artery of Heubner, which provides deep perfusion to the basal ganglia area.

Spinal Arteries

Finally, the blood supply extends to the lower regions of the central nervous system via the Anterior Spinal Artery, which runs along the midline, and the Posterior Spinal Artery.

Clinical Correlation: Because the lenticulostriate arteries are small and branch directly from the high-pressure MCA, they are highly susceptible to rupture from hypertension, often leading to intracerebral hemorrhages in the basal ganglia.