- published: 24 May 2016
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Fear is a feeling induced by perceived danger or threat that occurs in certain types of organisms, which causes a change in metabolic and organ functions and ultimately a change in behavior, such as fleeing, hiding or freezing from perceived traumatic events. Fear in human beings may occur in response to a specific stimulus occurring in the present, or in anticipation or expectation of a future threat perceived as a risk to body or life. The fear response arises from the perception of danger leading to confrontation with or escape from/avoiding the threat (also known as the fight-or-flight response), which in extreme cases of fear (horror and terror) can be a freeze response or paralysis.
In humans and animals, fear is modulated by the process of cognition and learning. Thus fear is judged as rational or appropriate and irrational or inappropriate. An irrational fear is called a phobia.
Psychologists such as John B. Watson, Robert Plutchik, and Paul Ekman have suggested that there is only a small set of basic or innate emotions and that fear is one of them. This hypothesized set includes such emotions as joy, sadness, fright, dread, horror, panic, anxiety, acute stress reaction and anger.
Red is the color at the end of the spectrum of visible light next to orange and opposite violet. Red color has a predominant light wavelength of roughly 620–740 nanometres. Red is one of the additive primary colors of visible light, along with green and blue, which in Red Green Blue (RGB) color systems are combined to create all the colors on a computer monitor or television screen. Red is also one of the subtractive primary colors, along with yellow and blue, of the RYB color space and traditional color wheel used by painters and artists.
Reds can vary in shade from very light pink to very dark maroon or burgundy; and in hue from the bright orange-red scarlet or vermilion to the bluish-red crimson.
Red was widely used in prehistoric cave art, made with red hematite or iron oxide, or red ochre. Early civilizations in China, the Middle East and Europe made red dyes from the madder plant or from a tiny insect called Kermes vermilio. Civilizations in the Americas made brilliant reds from another scale insect, the cochineal; ancient Chinese artists during the Han Dynasty used dye from the madder plant to color silk and pigments from lead oxide to color pottery.