Description of Curious

Curiosity (from Latin curiosus "careful, diligent, curious," akin to cura "care") is an emotion related to natural inquisitive behavior such as exploration, investigation, and learning, evident by observation in human and many animal species. The term can also be used to denote the behavior itself being caused by the emotion of curiosity. As this emotion represents a drive to know new things, curiosity is a major driving forces behind scientific research and other disciplines of human study.

Causes
Children peer over shoulders to see what their friends are reading.
Although many living beings have an innate capability of curiosity, it should not be categorized as an instinct because it is not a fixed action pattern; rather it is an innate basic emotion because while curiosity can be expressed in many ways, the expression of an instinct is typically more fixed and less flexible. Curiosity is common to human beings at all ages from infancy through adulthood,and is easy to observe in many other animal species. These include apes, cats, rodents, fish, reptiles, and insects; as well as many others.Many aspects of exploration are shared among all beings, as all known terrestrial beings share similar aspects: limited size and a need to seek out food sources.

In fact, in its development as wonder or admiration, it is generally curiosity that makes a human being want to become an expert in a field of knowledge Though humans are sometimes considered particularly curious, they sometimes seem to miss the obvious when compared to other animals. What seems to happen is that human curiosity about curiosity itself (i.e. meta-curiosity or meta-interest), combined with the ability to think in an abstract way, leads to mimesis, fantasy and imagination - eventually leading to an especially human way of thinking ("human reason"), which is abstract and self-aware, or conscious.

Brain
The degree to which a person says that they have curiosity about trivia questions links to activity both in the Broca's area in their left inferior frontal gyrus and in the putamen in their basal ganglia. This suggests that people experiencing curiosity activate not only parts of their brain that comprehend and anticipate information, but also those parts in which such information acts as a secondary reinforcer or reward. Curiosity also increases activity in memory areas such as the hippocampus when subjects guess trivia questions incorrectly - this suggests that it might act to enhance a person's long-term memory for surprising new information. Such activation linked to curiosity predicted better recall of surprising answers one or two weeks later.
Dopamine receptors in part of the hippocampus called the dentate gyrus contribute to the generation of a spontaneous exploratory behavior in mice, that may be akin to curiosity in humans. These receptors, and the protein NCS-1 that regulates their expression, also play important roles in plasticity and learning and therefore may represent a molecular link between intelligence and curiosity.

Morbid curiosity

A crowd mills around the site of a car accident in Czechoslovakia in 1980.A morbid curiosity is an example of addictive curiosity, the object of which is death, violence, or any other event that may cause harm physically or emotionally (see also: snuff film), the addictive emotion being explainable by meta-emotions exercising pressure on the spontaneous curiosity itself. According to Aristotle, in his Poetics we even "enjoy contemplating the most precise images of things whose sight is painful to us." (This aspect of our nature is often referred to as the 'Car Crash Syndrome' or 'Trainwreck Syndrome', derived from the notorious supposed inability of passersby to ignore such accidents.)