In human anatomy, the forehead is an area of the

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals ...

bounded by three features, two of the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

and one of the scalp. The top of the forehead is marked by the hairline, the edge of the area where hair on the scalp grows. The bottom of the forehead is marked by the

supraorbital ridge The brow ridge, or supraorbital ridge known as superciliary arch in medicine, is a bony ridge located above the eye sockets of all primates. In humans, the eyebrows are located on their lower margin. Structure The brow ridge is a nodule or cre ...

, the bone feature of the skull above the eyes. The two sides of the forehead are marked by the temporal ridge, a bone feature that links the supraorbital ridge to the

coronal suture The coronal suture is a dense, fibrous connective tissue joint that separates the two parietal bones from the frontal bone of the skull. Structure The coronal suture lies between the paired parietal bones and the frontal bone of the skull ...

line and beyond. However, the eyebrows do not form part of the forehead. In ''

Terminologia Anatomica ''Terminologia Anatomica'' is the international standard for human anatomical terminology. It is developed by the Federative International Programme on Anatomical Terminology, a program of the International Federation of Associations of Anatomi ...

'', ''sinciput'' is given as the Latin equivalent to "forehead". (Etymology of ''sinciput'': from ''semi-'' "half" + ''caput'' "head".)

Structure

The bone of the forehead is the squamous part of the frontal bone. The overlying muscles are the occipitofrontalis, procerus, and corrugator supercilii muscles, all of which are controlled by the temporal branch of the facial nerve. The sensory nerves of the forehead connect to the ophthalmic branch of the

trigeminal nerve In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and che ...

and to the cervical plexus, and lie within the subcutaneous fat. The motor nerves of the forehead connect to the facial nerve. The ophthalmic branch of the trigeminal nerve, the supraorbital nerve, divides at the orbital rim into two parts in the forehead. One part, the superficial division, runs over the surface of the occipitofrontalis muscle. This provides sensation for the skin of the forehead, and for the front edge of the scalp. The other part, the deep division, runs into the occipitofrontalis muscle and provides frontoparietal sensation. Blood supply to the forehead is via the left and right superorbital, supertrochealar, and anterior branches of the superficial temporal artery.

Function

Expression

The muscles of the forehead help to form facial expressions. There are four basic motions, which can occur individually or in combination to form different expressions. The occipitofrontalis muscles can raise the

eyebrow An eyebrow is an area of short hairs above each eye that follows the shape of the lower margin of the brow ridges of some mammals. In humans, eyebrows serve two main functions: first, communication through facial expression, and second, prev ...

s, either together or individually, forming expressions of surprise and quizzicality. The corrugator supercilii muscles can pull the eyebrows inwards and down, forming a frown. The procerus muscles can pull down the centre portions of the eyebrows.

Wrinkles

The movements of the muscles in the forehead produce characteristic

wrinkle A wrinkle, also known as a rhytid, is a fold, ridge or crease in an otherwise smooth surface, such as on skin or fabric. Skin wrinkles typically appear as a result of ageing processes such as glycation, habitual sleeping positions, loss of ...

s in the skin. The occipitofrontalis muscles produce the transverse wrinkles across the width of the forehead, and the corrugator supercilii muscles produce vertical wrinkles between the eyebrows above the nose. The procerus muscles cause the nose to wrinkle.

Society and culture

In physiognomy and

phrenology Phrenology () is a pseudoscience which involves the measurement of bumps on the skull to predict mental traits.Wihe, J. V. (2002). "Science and Pseudoscience: A Primer in Critical Thinking." In ''Encyclopedia of Pseudoscience'', pp. 195–203. C ...

, the shape of the forehead was taken to symbolise intellect and intelligence. "Animals, even the most intelligent of them,", wrote Samuel R. Wells in 1942, "can hardly be said to have any forehead at all, and in natural total idiots it is very diminished".

Pseudo-Aristotle Pseudo-Aristotle is a general cognomen for authors of philosophical or medical treatises who attributed their work to the Greek philosopher Aristotle, or whose work was later attributed to him by others. Such falsely attributed works are known as ...

, in '' Physiognomica'', stated that the forehead is governed by

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...

. A low and little forehead denoted magnanimity, boldness, and confidence; a fleshy and wrinkle-free forehead, litigiousness, vanity, deceit, and contentiousness; a sharp forehead, weakness and fickleness; a wrinkled forehead, great spirit and wit yet poor fortune; a round forehead, virtue and good understanding; a full large forehead, boldness, malice, boundary issues, and high spirit; and a long high forehead, honesty, weakness, simplicity, and poor fortune. In fighting, slamming one's forehead into one's opponent is termed a

headbutt A headbutt is a targeted strike with the head, typically (when intentional) involving the use of robust parts of the headbutter's cranium as the area of impact. The most effective headbutts strike the most sensitive areas of an opponent, such as ...

References

External links

* {{Authority control Human head and neck Facial features