http://en.wikipedia.org/wiki/Pareidolia wrote:
<<Pareidolia (parr-i-doh-lee-ə) is a psychological phenomenon involving a vague and random stimulus (often an image or sound) being perceived as significant. Common examples include seeing images of animals or faces in clouds, the man in the moon or the Moon rabbit, and hearing hidden messages on records played in reverse. The word comes from the Greek para- – "beside", "with", or "alongside"—meaning, in this context, something faulty or wrong (as in paraphasia, disordered speech) and eidōlon – "image"; the diminutive of eidos – "image", "form", "shape".
Pareidolia is a type of
apophenia.
Carl Sagan hypothesized that as a survival technique, human beings are "hard-wired" from birth to identify the human face. This allows people to use only minimal details to recognize faces from a distance and in poor visibility but can also lead them to interpret random images or patterns of light and shade as being faces. The evolutionary advantages of being able to identify friend from foe with split-second accuracy are numerous; prehistoric (and even modern) men and women who accidentally identify an enemy as a friend could face deadly consequences for this mistake. This is only one among many evolutionary pressures responsible for the development of the modern facial recognition capability of modern humans.
In Cosmos: A Personal Voyage Sagan claimed that Heikegani crabs occasional resemblance to Samurai resulted in their being spared from capture and thus exaggerate the trait in their offspring, a hypothesis proposed by Julian Huxley in 1952. Japanese researcher Chonosuke Okamura self-published a famous series of reports titled "Original Report of the Okamura Fossil Laboratory" in which he described tiny inclusions in polished limestone from the Silurian period (425 mya) as being preserved fossil remains of tiny humans, gorillas, dogs, dragons, dinosaurs, and other organisms, all of them only millimeters long, leading him to claim "There have been no changes in the bodies of mankind since the Silurian period ... except for a growth in stature from 3.5 mm to 1,700 mm." Okamura's research earned him a winner of the Ig Nobel Prize in biodiversity.
A 2009 magnetoencephalography study found that objects incidentally perceived as faces evoke an early (165 ms) activation in the ventral fusiform cortex, at a time and location similar to that evoked by faces, whereas other common objects do not evoke such activation. This activation is similar to a slightly earlier peak at 130 ms seen for images of real faces. The authors suggest that face perception evoked by face-like objects is a relatively early process, and not a late cognitive reinterpretation phenomenon.
This study helps to explain why people identify the line drawing at the top of this article as a "face" so quickly and without hesitation; precognitive processes are activated by the "face-like" object, which alert the observer to the emotional state and identity of the subject - even before the conscious mind begins to process - or even receive - the information. The "stick figure face," despite its simplicity, conveys mood information (in this case, disappointment or mild unhappiness); it would be just as simple to draw a stick figure face that would be perceived (by most people) as hostile and aggressive. This robust and subtle capability is the result of eons of natural selection favoring people most able to quickly identify the mental state, for example, of threatening people, thus providing the individual an opportunity to flee and fight another day. In other words, processing this information subcortically (and therefore subconsciously) - before it is passed on to the rest of the brain for detailed processing - accelerates judgment and decision making when alacrity is paramount. This ability, though highly specialized for the processing and recognition of human emotions also functions to determine the demeanor of wildlife.
There are a number of conditions that can cause an individual to lose his/her ability to recognize faces; stroke, tumors, and trauma to the ventral fusiform gyrus are the most common culprits. This is known as prosopagnosia.>>