What is the primary source of blood flow to the brain?

The primary source of blood flow to the brain is through the internal carotid arteries. These arteries branch off from the common carotid arteries and ascend into the skull, where they further divide into the anterior and middle cerebral arteries. These branches supply crucial regions of the cerebral cortex, which are responsible for many essential functions such as reasoning, movement, sensation, language, and visual processing.

While the vertebral arteries also contribute to the blood supply of the brain, particularly the posterior circulation, the internal carotids play a more dominant role by supplying a larger portion of the cerebral hemispheres. The aorta branches and the subclavian arteries contribute to overall systemic circulation and peripheral regions, but do not serve as the primary conduits for oxygen-rich blood into the brain itself. This distinction highlights the essential role of the internal carotid arteries in maintaining cerebral perfusion and supporting neurological function.