They are great mimics of other neurologic disorders. Symptoms occur if the tumor directly damages the nerves in the brain or central nervous system or if its growth imposes pressure on the brain. Some gliomas develop gradually and symptoms may be subtle for a long time, making an early diagnosis difficult. Headache is probably the most common symptom of a brain tumor. Headaches caused by brain tumors may rouse a person from sleep and may worsen with coughing or exercise or with a change in body position.
Some people also experience neck pain.
As with headaches, however, seizures are not commonly caused by brain tumors. Often tumors cause partial seizures, in which one area of the brain is affected. In such cases, a person does not lose consciousness but may experience confusion, jerking movements, tingling, or odd mental and emotional events. Generalized seizures are caused by disturbances of nerve cells in diffuse areas of the brain and therefore have a more severe and widespread effect on the patient. Gastrointestinal symptoms are also common and include nausea.