Headache pain results from signals interacting between the brain, blood vessels, and surrounding nerves. During a headache, specific nerves of the blood vessels and head muscles are activated and send pain signals to the brain. It's not clear, however, why these signals are activated in the first place.
There is a migraine "pain center" or generator in the mid-brain area. A migraine begins when hyperactive nerve cells send out impulses to the blood vessels, causing constriction, followed by the dilation of these vessels and the release of prostaglandins, serotonin, and other inflammatory substances that cause the pulsation to be painful. Serotonin is a naturally occurring chemical essential for certain body processes.
Headaches that occur suddenly (acute-onset) are usually due to an illness, infection, cold or fever. Other conditions that can cause an acute headache include sinusitis (inflammation of the sinuses), pharyngitis (inflammation or infection of the throat) or otitis (ear infection or inflammation).
In some cases, the headaches may be the result of a blow to the head (trauma) or rarely a sign of a more serious medical condition.
Common causes of tension headaches or chronic nonprogressive headaches include emotional stress related to family and friends, work or school; alcohol use; skipping meals; changes in sleep patterns; excessive medication use; tension and depression. Other causes of tension headaches include eyestrain and neck or back strain due to poor posture.
The types of activities that can lead to poor neck posture include sitting at a computer for extended periods of time, reading with the head bent forward, sitting while slouching in a chair or on a couch, sleeping with the head or neck in odd positions, or any other activity that places the head in a position forward to the body. This leads to the conclusion that headaches and neck pain can be caused by sitting at a computer.
Headaches can also be triggered by specific environmental factors that are shared in a family's household, such as exposure to second-hand tobacco smoke, strong odors from household chemicals or perfumes, exposure to certain allergens or eating certain foods. Stress, pollution, noise, lighting and weather changes are other environmental factors that can trigger headaches for some people.
Too much physical activity can also trigger a migraine in both adults and children. Be sure to consult a doctor to find out what is causing your headaches.