What happens to the brain during an ischemic stroke?

During an ischemic stroke, the brain experiences a significant reduction in blood flow due to a blockage in one or more of the blood vessels supplying the brain. This obstruction can be caused by a blood clot or a buildup of fatty deposits, leading to a decrease in oxygen and nutrients available to brain tissues. When blood flow is compromised, neurons in the affected areas begin to die, and this can result in loss of function related to the specific area of the brain involved. Understanding this mechanism is crucial for recognizing the signs and symptoms of an ischemic stroke and responding effectively to minimize brain damage. The other options do not accurately reflect what occurs in an ischemic stroke, as the condition is characterized by insufficient blood flow, not excess or increased activity.