Symptoms will depend upon the whereabouts of the clot in the blood circulation of the brain. Obstruction of a blood vessel in this way is also referred to as a stroke. Common symptoms include paralysis and/or altered sensation of a part or a whole one side of the body, difficulty with speech, difficulty with comprehension and problems with vision. A Stroke is a medical emergency and if you should experience symptoms such as these, it is advisable to go to the hospital as soon as is possible. Time is an important factor as clot-busting drugs can be given in this setting, but only within a three-hour time window from the onset of first symptom. Those who suffer a stroke can subsequently experience seizures.