Change blindness
Change blindness is a psychological phenomenon where individuals fail to notice changes in their environment, which can range from minor alterations to significant transformations. This occurs because the human brain is bombarded with numerous stimuli, and its capacity to process information is limited. Even with perfect vision, a person may overlook visible changes simply because their attention is focused elsewhere. For instance, in busy scenarios, such as a crowded street, a person might miss a dramatic change on an electronic billboard because their attention is diverted to other elements in the environment.
Researchers have conducted experiments illustrating change blindness, such as swapping individuals during a brief obstruction of view, often without the observer noticing the switch. This phenomenon also relates to memory, as it can affect how individuals recall events, making eyewitness testimonies unreliable in some cases. Additionally, change blindness shares similarities with unintentional blindness, where a person may not see something clearly visible due to focused attention. Understanding change blindness is crucial, especially in contexts like driving or online communication, as it emphasizes the importance of being aware of one's perceptual limitations and the potential consequences of missing vital information.
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Subject Terms
Change blindness
Change blindness is the name of the phenomenon that occurs when people fail to notice changes that take place in their environments. The changes that are overlooked because of change blindness can be minor or significant. Human brains experience change blindness because the brain has so many stimuli dividing its attention that it cannot notice all the changes happening around it. Change blindness is related to other mental phenomena, such as unintentional blindness.
Background
The eye, the optic nerve, and the brain mainly control a person's sense of vision. These parts work together to collect, transmit, and decode information about what a person sees. The eye is the body part that collects the visual information. The eye is connected to the brain through a nerve called the optic nerve. The image information is sent through electric impulses from the eye to the brain. The brain decodes that information and sends signals to other parts of the body based on the decoded information. For example, if a person sees someone smiling, they might smile back. If a person sees an object falling, they might move to catch the falling object.
Although the word blindness may make it seem as if this phenomenon has something to do with vision quality, it has nothing to do with a person's ability to see. A person experiencing change blindness can have perfect vision. Instead, change blindness deals with the brain's decoding and understanding of the visual signals sent by the eye and optic nerve. Change blindness does not mean a person is unable to see change; instead, it means a person is unable to register a change that is clearly visible. The human brain is made up of approximately 100 billion neurons. These cells transmit information. They also send signals to other parts of the central nervous system. The neurons in the brain work incredibly quickly. They can take in a great deal of information at one time. However, their ability to take in and process information is finite.
Overview
Change blindness happens when a person does not notice a change because their brain has too many stimuli to decode and does not decode a change that occurs. For example, a person on a busy street might be observing traffic in the street, people walking past, and lights flashing on buildings. A person walking through such a busy scene could not perceive all the stimuli on the street. Therefore, a person experiencing all those stimuli might not notice a change on an electronic billboard, even if the billboard was clearly visible to the person and the change was dramatic. Scientists have conducted experiments to test change blindness in people. One experiment various researchers have conducted involves Person A asking a stranger for directions. During their conversation, the researcher obstructs the stranger's view of Person A, perhaps by having a person with a large object walk between them. During that time, Person A switches places with Person B. After the obstruction is moved out of the way, the stranger continues talking to Person B. About half the time, the stranger does not notice that Person A has been replaced with Person B.
People perceive the world around them with their senses. Often, people feel as though they can see and hear everything that is happening around them, but that is not true. The human brain is able to process only so much information at one time. Humans are constantly bombarded by information and stimuli. The brain filters out some of the information that it does not have the capacity to process. If something changes and the human mind does not have the capacity to register the change, a person can experience change blindness and not notice the change.
Change blindness is related to memory. Since memories are formed based on what we perceive around us, our memories can be affected by change blindness. People may experience situations and believe they have correctly remembered all the details of the scene. Yet, because of change blindness, those people may not have correctly perceived their surroundings. This implication becomes especially important when people recount crimes or other traumatic events. Eyewitness testimony in criminal cases has often proven to be wrong. This could be because people who experience the trauma of a crime have sensory overload and experience change blindness or something similar, making their memories unreliable.
Unintentional blindness is related to change blindness. During unintentional blindness, a person may not see something that is plainly and clearly visible. This usually happens when a person is focused on something in particular. For example, a person walking toward a friend at the mall might not notice another acquaintance walking past. Although the acquaintance is not hidden from view, the person walking does not take notice of them. That person's attention is focused on the friend, causing unintentional blindness of the acquaintance. The same processes that cause change blindness lead to unintentional blindness, as the mind is focused on one particular thing and cannot decode all the stimuli entering the brain. People believe that if something important happens, they will instantly notice it. However, the opposite is often true. People can miss important events happening around them because their brains do not decode the stimuli to tell them that something critical is taking place.
Understanding change blindness and the mind's limits can help scientists better understand the brain in general. Scientists want to understand how the brain chooses which stimuli to react to. Scientists also want to know how much stimuli an average brain can process at one time. It is important for people to understand the limits of the brain and phenomena such as change blindness, as it can have negative consequences and, in general, people tend to underestimate their change blindness. For example, people who are driving might not notice a pedestrian in the road who was not there only a second before.
As technology evolves, change blindness research increasingly investigates the impact of Zoom or Google Meet meetings and other online communications on the prevalence of change blindness. Scientists aim to understand the underlying mechanisms that drive an individual's change blindness, such as the perceived importance of the call or the background of a meeting participant's screens. This research has critical applications for virtual learning, workplaces, and more.
Bibliography
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