A brain tumor is a mass of abnormal cells in the brain. The brain stem includes the midbrain, pons and medulla oblongata and regulates body functions such as blood pressure, heart rate and breathing. The reticular formation is the central core of the brain stem and controls eating and sleeping, consciousness, drowsiness and attention. Brain tumors often grow slowly with symptoms presenting over time. Tumors occurring in the brain stem can impair vital functions and produce a variety of symptoms.
Vomiting and Headache
Vomiting is the most common symptom of a brain stem tumor. People will often note that they vomit upon waking and then feel better. This may be accompanied by a headache that lessens after vomiting. People who have a headache due to a brain tumor often note that these headaches are severe upon waking but ease up throughout the day. They may also notice that coughing, exertion or changing position exacerbates these headaches, according to "The New York Times" Health Guide. Headaches occurring due to a brain tumor often do not typically respond to usual headache treatments.
Mass Effect
People with a brain stem tumor also suffer from a symptom known as the mass effect. Mass effect occurs due to increased pressure in the skull. This increase in pressure can occur for a number of reasons. The tumor may cause swelling, compressing the brain in the skull, or the tumor may also cause a blockage, causing fluid to build up in the skull. Mass effect can cause drowsiness and changes in mental acuity. Mass effect may also impair vision if the tumor is pressing on the optic nerve. People may experience blurred or double vision, loss of peripheral vision and inability to move one or both eyes. The American Brain Tumor Association explains that increased intracranial pressure, or IICP, can become a life-threatening situation if not dealt with promptly.
Neurological Symptoms
Muscle weakness on one side of the face is another symptom of a tumor of the brain stem. People may experience slackness on one side of the face, a drooping eyelid or a one-sided smile. People mistakenly think they are having a stroke. Because the brain stem controls consciousness, drowsiness and attention a tumor in this area may cause drowsiness or lethargy, head tilt, hearing loss and personality changes over time.
