Face inversion effect

The face inversion effect is a phenomenon in which people have difficulty identifying faces that are inverted, or upside down. The phenomenon happens when the brain tries to encode the information it perceives about a face. Scientists have studied the effect by asking people to match or compare pictures of faces that are upright and pictures of faces that are inverted. Scientists have also studied the face inversion effect and face perception in general using magnetic resonance imaging and other imaging techniques.

Background

Face perception, or the recognition of faces, is an important human ability. Recognizing faces is one of the most important evolutionary skills that humans have developed. Scientific studies have shown that humans are constantly monitoring each other’s faces for information that they can use. Studies have also found that individuals who have problems processing facial information during face-to-face interaction often have less developed social abilities. Facial recognition allows people to recognize individuals and process information about other people’s emotions. Any limits on these abilities can affect social behavior. People with various mental conditions—including schizophrenia, autism spectrum disorder, and Alzheimer’s disease—have sometimes been found to have problems recognizing and processing faces.

Overview

In general, many objects are more challenging for people to recognize when they are inverted than if they are upright. Scientists have found the face inversion effect that faces are more difficult for humans to recognize upside than other objects. For example, although it may be difficult for a person to recognize a house that is inverted, it is more difficult for the person to recognize a face that is inverted. The face inversion effect is extremely common. It can be observed in scientific studies where scientists ask people to name, classify, or match faces in photographs or drawings.

The effect takes place in the brain while it is in the process of storing information as memory. Memory and the ability to retrieve the stored information are essential to survival so that humans do not have to keep relearning basic skills. The brain processes a great deal of information from various sources, including images, sounds, and scents. The memory process has three main stages: encoding, storage, and retrieval. During the encoding stage, the information people take in through their senses has to be converted into a form that the brain can store. For example, when a person reads a word, the person’s brain will change the word into a sound or a meaning. This will make the information easier to store inside the brain. Scientists believe that information that is encoded into short-term memory is most often coded acoustically. They believe that information that is encoded into long-term memory is most often coded by meaning, or through semantic coding. The face inversion effect takes place during the encoding stage of the memory process. It most likely happens when the brain is changing the information into something that it can store for later use.

Scientists believe that both hemispheres of the brain are involved in facial recognition and processing. However, scientists also believe that the different hemispheres are involved in different parts of the processing. The right hemisphere is thought to be involved in the holistic processing of facial information, meaning it processes information about the face as a whole. However, the left hemisphere is associated more with facial analysis. Therefore, the right side of the brain is the most likely brain part to be part of the face inversion effect, since it is during the encoding that the effect most likely happens.

Scientists have various theories about why humans need more time to recognize inverted faces than inverted objects. Some scientists believe a theory known the configural information hypothesis may lead to the face inversion effect. This theory states that the effect most likely happens because the brain processes faces as a whole instead of as parts. The brain is more likely to process objects by their parts. Scientists believe that when the image of a face is inverted, the brain is forced to process the face by its parts, rather than a whole. Because the brain has to take this extra, unusual step, it takes longer for the brain to process the information.

The face inversion effect affects face perception and much of the information people collect from face perception. However, scientists have found that some information is more affected than others. For example, attraction is more affected by face inversion as it takes far more time to assess attractiveness in an upside-down face than in an upright one. Yet, studies indicate that beauty is more affected by face inversion than the concept of “cuteness.” Studies have also shown that face inversion effect alters a person’s ability to perceive changes in faces. For example, if a test subject is shown the same face with two different eye colors, the subject will most likely notice the change more quickly in the upright face than in the inverted face.

Scientists have also noted that the effect is more noticeable in adults than in infants and small children. Studies indicate that the effect does not change the facial perception in infants when the faces are unknown to the infant. However, scientists have found that infants may experience the effect when they observe upright and inverted images with which they are familiar. Scientists believe that face inversion effect increases with age because people who have more experience looking at faces have become more adept at processing them as a whole rather than by parts.

Bibliography

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