Did you know that the brain can not feel pain? It does not have any pain receptors. So what then, is a headache? A headache is the result of a process called pain referral . The body transmits pain to a region of the body other than the area where the pain actually originates from. An well known example of pain referral involves heart attacks: when someone is experiencing a heart attack, he or she will feel the pain in his or her left arm (and not in his or her heart). Headaches are usually a signal that something involving or surrounding the brain is not functioning properly.
If the headache arises near the eyes and/or blurred or fuzzy vision is experienced, this is a sign that the vertebral artery (the artery that supplies blood to the brain) is being squeezed. When the vertebral artery is squeezed by neck muscles due to poor posture (e.g. staring at a computer screen for too long can cause poor neck posture), not enough blood is making it to the brain. When blood supply is limited, the brain chooses which area is the least important and sort-of directs the blood away from this non-so-so-essential brain area. Often the area of the brain "cut-off" is the vision part (part of the occipital lobe), hence the blurred vision.
If a headache arises at the back of the head, this is likely a sign that the occipital nerve is being pinched (likely also due to bad posture) and, as a result, is radiating the pain (again, the brain doesn't feel pain, but nerves around it do).
I will likely be talking about headaches on this blog a lot because they affect so many people. I have touched on two causes of headaches, however there are MANY reasons why people get heads (in the future I will discuss some more). Nevertheless, one thing is for sure: a headache is a "cry for help", a way in which the body tells you that something isn't right!