The symptoms of glioblastoma vary depending on where in the brain the tumors are located, but they often include headaches, nausea and vomiting, according to the American Brain Tumor Association. Pressure from the tumor can also cause mood disorders and personality changes.
Memory loss, speech difficulties, vision problems, drowsiness and weakness on one side of the body are also common symptoms of glioblastomas. Approximately 15 percent of primary brain tumors are glioblastomas, according to the ABTA, and their cause is unknown. Symptoms tend to come on quickly and can be unpredictable because they are caused by pressure on different parts of the brain.