What Happens to the Brain When You Get a Headache?

Headaches can be a nuisance---your head is pounding, you cannot concentrate and nothing seems to make the throbbing pain go away. According to Dr. Lawrence Robbins, author of "Headaches", up to 50 million people annually have debilitating headaches. However, headaches are not indicators of pain in your brain, but your brain is responsible for the chemicals involved to create a headache.

Location

Headaches do not occur in your brain: while your brain can perceive pain in different areas of your body, the brain itself cannot feel pain. A headache is caused by swelling of the blood vessels around the brain, as well as tension in the surrounding muscles and nerves. Tension headaches, for example, are caused by muscles in your neck and head tightening up.

Neurotransmitters

Three of the most common types of headaches---tension headaches, migraines and cluster headaches---may be caused by serotonin levels. Serotonin is an essential neurotransmitter in the brain, which is involved in mood, sleep and blood vessel sizes. According Dr. Robbins, when a headache starts, an electrical signal passes through the brain. This causes the blood vessels to contract, and serotonin enters the surrounding tissues. However, when the blood vessels expand again, the lack of serotonin results in a migraine or tension headache. Cluster headaches, which are the most painful type of headache, may be caused by a serotonin imbalance as well. The start of the electrical signal is due to headache triggers, such as stress, anxiety, caffeine or certain foods.

Estrogen

During a woman's menstruation, she is more prone to migraines. According to Dr. Robbins, 70% of women experience menstrual migraines. It is hypothesized that the cause of these headaches is the shift in estrogen, which occurs during a woman's period, even if she is on a hormone birth control or nearing menopause. The reason behind estrogen causing headaches is not known, but it may have an effect on chemicals in the brain.