The forehead (Latin: sinciput) is a part of the head bounded by three features – one of the scalp and two of the skull. It constitutes the upper third of the face. Hairline, which represents the edge of the area where hair grows, marks the top of the forehead, while the bottom of the forehead is marked by the supraorbital ridge. That is the bone feature just above the eyes. When it comes to the sides of forehead, there are temporal ridges which are marking it. These temporal ridges represent also a bone feature which links the supraorbital ridge to the coronal suture line and beyond.
The forehead comprises the Squama Frontalis – the plate-like portion of the frontal bone of the skull. The sensory nerves of the forehead lie within the subcutaneous fat. They are connected to the ophthalmic branch of the trigeminal nerve and the cervical plexus, while the motor nerves are connected to the facial nerve. The musculature of the forehead comprises the occipitofrontalis, procerus, and corrugator supercilii muscles. The temporal branch of the facial nerve mentioned above controls all of them. Left and right supraorbital, supertrochealar, and anterior branches of the temporal artery supply blood to the forehead.
The supraorbital nerve divides into two parts in the forehead – the superficial division, which provides sensation for the skin on the forehead and front edge of the scalp, and the deep division, which provides frontoparietal sensation.
Functions of the forehead
With the help of muscles of the forehead facial expressions are formed. There are four basic motions. They could occur individually or in combination, in order to form different expressions. The best example is following: the occipitofrontalis muscles can raise the eyebrows. They could be raised either together or individually, aiming different expression: surprise or suspect. Of course, there are other examples like pulling the eyebrows inwards and down with the help of the corrugator supercilii muscles, so that person can express a frown.
The movements of the muscles in the forehead cause appearing of the wrinkles in the skin. The occipitofrontalis muscles are “guilty” for the transverse wrinkles across the width of the forehead, while the corrugator supercilii muscles cause vertical wrinkles between the eyebrows. Lastly, the procerus muscles help in process of the nose wrinkling.
- It is believed that form of the forehead reflects the character of a person. So, following the belief, person with the high brow (brow=forehead) has a superior intellect and is sophisticated. On the other hand, low brow is associated with primitive species of humanity and indicates primitivism and ignorance.
- Another interesting thing about forehead is that it is believed to be a site of spirituality in some religions. The center of the forehead in Hindu tradition is, as you all probably know, the location of a third eye. In other words it is the location of spiritual insight. Also, Hindu gods are mostly represented with a third eye in the middle of their foreheads. Muslims are touching their foreheads to the floor when bowing toward Mecca. In addition, some Tibetan meditation practices focus on the center of the forehead.