![]() Headhunting has been practiced across the Americas, Europe, Asia, and Oceania for millennia. Headhunting is the practice of taking and preserving a person's head after killing the person. Īncient Greeks had a method for evaluating sexual attractiveness based on the Golden ratio, part of which included measurements of the head. The head is a source for many metaphors and metonymies in human language, including referring to things typically near the human head ( "the head of the bed"), things physically similar to the way a head is arranged spatially to a body ("the head of the table"), metaphorically ("the head of the class"), and things that represent some characteristics associated with the head, such as intelligence ("there are a lot of good heads in this company"). Despite this depiction, advances in neurobiology have shown that the functional diversity of the brain means that a difference in overall brain size is only slightly to moderately correlated to differences in overall intelligence between two humans. Additionally, in science fiction, an extraterrestrial having a big head is often symbolic of high intelligence. People who have greater than average intelligence are sometimes depicted in cartoons as having bigger heads as a way of notionally indicating that they have a "larger brain". Dayak people were feared for their headhunting practices Human infants are biologically programmed to recognize subtle differences in anthropomorphic facial features. When observing a relatively unfamiliar species, all faces seem nearly identical. Humans easily differentiate between faces because of the brain's predisposition toward facial recognition. Humans can process information faster by having this central nerve cluster.įor humans, the front of the head (the face) is the main distinguishing feature between different people due to its easily discernible features, such as eye and hair colors, shapes of the sensory organs, and the wrinkles. Together, these organs function as a processing center for the body by relaying sensory information to the brain. The head contains sensory organs: two eyes, two ears, a nose and tongue inside of the mouth. Dorsal rami of cervical nerves (blue) and others are in picture which show following in upper column.The cutaneous innervation of the head is as follows: The borders designated by diagrams in the 1918 edition of Gray's Anatomy are similar but not identical to those generally accepted today. Modern texts are in agreement about which areas of the skin are served by which nerves, but there are minor variations in some of the details. ![]() Sensation to other portions of the head is provided by the cervical nerves. The sensation to the face is provided by the branches of the trigeminal nerve, the fifth cranial nerve. The twelve pairs of cranial nerves provide the majority of nervous control to the head. Nerve supply Sensory areas of the head, showing the general distribution of the three divisions of the fifth nerve. The area inside the skull also receives blood supply from the vertebral arteries, which travel up through the cervical vertebrae. These supply the area outside of the skull ( external carotid artery) and inside of the skull ( internal carotid artery). The head receives blood supply through the internal and external carotid arteries. ![]() ![]() On either side of the mouth, the cheeks provide a fleshy border to the oral cavity. The face is the anterior part of the head, containing the eyes, nose, and mouth. The Zika virus was responsible for underdeveloped heads in the early 2000s. There have been odd incidences where human beings have abnormally small or large heads. The human head typically weighs between 2.3 and 5 kilograms (5.1 and 11.0 lb) Over 98% of humans fit into this range. The head rests on the neck, and the seven cervical vertebrae support it. The human head consists of a fleshy outer portion, which surrounds the bony skull. It supports the face and is maintained by the skull, which itself encloses the brain. In human anatomy, the head is at the top of the human body. ![]()
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