Change Blindness: Examples and Definition
What is Change Blindness?
To understand Change Blindness, look at this example. Stella is watching a movie with her mother. Halfway through the movie, during a particularly serious scene, Stella is appalled to hear her mother laugh. When asked why, her mother stated, "Did the directors really think no one would notice that the main character's tie suddenly changes from red to blue?" Confused, Stella rewinds the scene and watches it again. To her surprise, the protagonist's tie is red in one moment and blue in the next.
Stella experienced a phenomenon called change blindness. So, what is change blindness? Change blindness is the inability to detect minor changes that occur within the visual field. More simply put, it occurs when an individual does not notice a change in something they're actively watching. In many instances, these changes are obvious and apparent after being pointed out, as they were for Stella after she rewatched part of the movie.
This lesson explores change blindness examples and answers the following questions:
- What are real-world examples of change blindness?
- What are the differences between change blindness and inattentional blindness?
- Why does change blindness occur?
What Is Change Blindness?
Have you ever been so engrossed in a conversation at a party that you failed to notice that someone new is standing only six inches away from you, trying to get your attention? It's possible that you were so distracted that you didn't notice someone approaching you. But it's also entirely likely that you were experiencing change blindness.
Change blindness is a phenomenon that occurs when a person is unable to notice visual changes in their environment, despite the fact that they are often rather obvious. In cases of change blindness, the person isn't failing to notice small or insignificant changes, but will probably miss big changes, like someone standing next to them waving their hand.
Change Blindness Examples
Change blindness is a common experience that occurs in life. Individuals who have experienced change blindness will never know unless the change is directly pointed out or seen later. Explore change blindness examples to understand when and where this phenomenon may occur.
Michael's Goldfish
Michael went out of town one weekend and asked his friend Frank to watch his house for him. Frank agreed and stayed a few nights at Michael's, making sure his plants were watered, his cat was fed, and the house was secure. The day before Michael returned, he called Frank and asked how his pet fish was doing. Frank, caught off guard, said that his fish was doing just fine. After the phone call, Fran frantically searched the house for a fish he hadn't realized existed. When he came across the small tank in the corner of Michael's office, the fish was already dead. Instead of telling his friend, Frank went to a local pet store and got a new fish. When Michael got home, he did not see the difference between this new fish and his old fish, even though they were not completely identical. Months later, a guilt-riddled Frank admitted to Michael what had happened. When Michael looked at his fish afterward, he noticed that this new fish was a slightly different color and had differently shaped fins.
Michael had experienced change blindness. Even though his fish had been swapped out with a somewhat different fish, Michael had not anticipated a change and thus never noticed it. It wasn't until his friend Frank confessed that Michael began to notice the differences.
Rosie's Testimony
Rosie gave testimony as a witness in a robbery. She stated that she had seen a man rob a convenience store at gunpoint. The defense attorney offered Rosie a blurry picture that had been taken from the security cameras that night and asked Rosie if the man in the picture was the man she had seen. Rosie examined the photo and stated that, even though the photo was blurry, she was confident the men were the same. The defense attorney then stated that the photo had been tampered with and the man's clothes changed. Based on this, he asked the jury to reconsider how accurate Rosie's memory truly was.
Rosie had experienced change blindness. Even though she was focusing on a photo taken on a night, she was present, and she was unable to see the differences in the clothes the man was wearing. Because of this, she stated that the man in the photo appeared the same as the man she had seen. While Rosie's identification could have been accurate, the defense attorney had used Rosie's change blindness to discredit her testimony.
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Change Blindness vs Inattentional Blindness
Another type of unaware blindness that occurs is inattentional blindness. Inattentional blindness occurs when a person is focusing on another task and thus doesn't notice the changes that take place around them. As with change blindness, changes that occur during inattentional blindness are often obvious after being pointed out. Choosing to focus on one stimulus and filtering out others is called attentional selection. In order to understand the difference between blindness versus inattentional blindness, it's important to consider where the observer's focus is at. In inattentional blindness, change typically occurs when someone's focus is elsewhere, such as paying attention to a complicated task. In change blindness, that individual may not be highly focused on something else, but the change still occurs unnoticed.
Example of Inattentional Blindness
Fatima is babysitting an infant and a toddler. During a diaper change, Fatima finds herself struggling to put the infant's new diaper on. No matter what she tries, the baby manages to cry, squirm, and wiggle away. In order to get the new diaper on, Fatima concentrates hard on anticipating the infant's movements. While she struggles with the diaper change, the toddler in front of her manages to take off his shirt, flip it inside out, and put it on backward. Even after Fatima successfully completes the diaper change, she doesn't notice the toddler's clothes have changed until his mother asks what happened upon coming home. Because Fatima's attention was pulled strongly to a particular task while the change occurred, she experienced change blindness where she did not notice the difference in clothing.
Origin of Inattentional Blindness
Inattentional blindness was brought to light by Daniel Simons in 1990. He noticed that participants failed to see a person in a gorilla costume walking through a basketball court in a film when asked to focus on basketball players on the same court. Thus, the participants were focusing heavily on the basketball players and missed a large and obvious scene.
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What Are the Causes of Change Blindness?
Change blindness occurs for multiple reasons. Perhaps the most common reason involves a human's limited attention resources. The human brain is unable to focus on everything in its environment at a single time. Consider a man walking his dog through the park. Even though he may be paying attention to the park around him, it is impossible for him to keep track of every person, what they're wearing, and what they're doing. The brain allocates its attention to the parts of the world around it that it deems most important. In the case of the man in the park, it may be paying more attention to his dog, the biker coming towards him, and the uneven pavement below.
Previous experiences may also result in change blindness. If someone sees the same scene day after day, they may come to expect that it will not change. For instance, a teacher may walk past a mural in their school thousands of times throughout their career without any change occurring. When the day comes that a student vandalizes the mural, the teacher may not notice it. This is because the teacher has observed the mural many times and never detected a change, so the brain allocates little attention to the mural under the preconceived notion that it has never changed in the past.
How an object is presented may also change whether change blindness occurs. For example, a play may require an object to be switched out a mid-scene. The change in that object would be much more noticeable if the stagehand swapping it was wearing bright clothing instead of clothing that helped them blend into the background.
Certain aspects of an individual may make them more likely to experience change blindness. Senior citizens experience change blindness more often. Conditions that impact attention, such as attention deficit disorders or drug use, may also influence the rates at which change blindness can occur.
Experiments on Change Blindness
Change blindness was first proposed in the late 1990s by Ronald Rensink and his team. Since then, multiple experiments have been conducted to better understand the situations that change blindness occurs and why it happens. A few examples of these experiments are provided in the table below:
Researcher | Experiment | Results |
---|---|---|
Blackmore et al. 1995 | Images were shown to participants with and without a visual interruption. | Individuals were more likely to experience change blindness when images had interruptions. |
O'regam, Rensink, and Clark 1999 | Identical images were shown to participants with and without splatters | Images with splatters were more likely to induce change blindness |
Levin et al. 2000 | Changes were made to a film and participants asked to identify changes | Few participants were able to notice the changes |
Lesson Summary
Change blindness occurs when an individual fails to notice a change that occurs within their environment. This typically occurs because a person's attention is a finite resource, and they cannot focus on all aspects of their environment at once. Change blindness may also happen when an individual has seen a constant observation multiple times and thus doesn't anticipate a change to occur, or if they're older, have attention-related conditions, or are under the influence of drugs. Change blindness was first mentioned in the late 1990s by Ronald Rensink and his team.
Attention selection is the ability to focus on a sole thing while filtering out other environmental stimuli. When attention selection leads to a considerable amount of information being filtered out, inattentional blindness may occur. This results when a person is so focused on a single object or task and thus does not notice other obvious occurrences in their environment. Inattentional bias was first proposed by Daniel Simons in 1990.
Experiments
Early experiments with change blindness focused largely on memory and perception when viewing pictures. For example, a person might be shown a photograph of a street scene in Egypt and told to memorize the image. Following that, they would be shown the same picture with certain elements added or taken away and asked to identify what's different. Very often the individual could recall the larger aspects of the picture but couldn't recognize the smaller changes.
An inability to recognize every change in a crowded or complicated picture is generally attributed to the brain's capacity to remember complex images in a broad scope. For example, they might remember looking at a picture of a crowded street with stores and restaurants, but they probably wouldn't notice that the names of the stores had changed. In general, this is because the brain cannot possibly process every element of an experience and has to prioritize what it believes to be important.
Inattentional Blindness
In the 1990s, researcher Daniel Simons conducted a fascinating study into change blindness that many people find unbelievable. In Simons' study, he asked participants to watch a video of a basketball being passed around between several people, with a particular focus on the basketball itself. When the experiment was over, Simons found that a large number of participants were so focused on watching the basketball being passed around that they failed to notice a man in a gorilla suit jumping around in front of the camera.
It's important to note that the change in Simons' video wasn't subtle. The gorilla is very obviously taking up much of the frame. Simons concluded that participants were experiencing inattentional blindness, which is when a person fails to notice a major change because they are so focused on another task. In this case, because participants were asked to focus on the movement of the basketball, their brains prioritized that task in order to do it properly, thereby missing the other things happening in the video.
In the case of Simons' study, participants engaged what's referred to as attentional selection, which is when a person selects certain things to focus on in order to achieve a task and filters out anything that is unrelated to the objective.
Causes
There are a number of theories about what causes a person's inability to recognize obvious changes in their environment, but most agree that the phenomenon is related to sensory processing. Broadly speaking, our brains have a limited capacity to detect and process everything in our environment. Instead, what the brain does is choose certain things to process, evaluate, and store, which allows other things to be missed or filtered out.
In simple terms, change blindness has a great deal to do with where a person directs their attention. In the case of the gorilla and the basketball, people focused their attention almost exclusively on one thing, which caused them to miss other elements or changes. Given that attention is often at the root of change blindness, a person's age or mental and physical health can influence how well they will notice changes in stimuli.
Another important factor is object presentation, which is how objects or other visual stimuli are presented or introduced. For example, in experiments involving identifying changes in pictures, the brain can detect some of the major changes because they are obvious, but they might miss smaller ones that are hidden throughout the image. Moreover, a person is more likely to notice something being added to an image than something being taken away. Researchers believe that this is because adding something to an image forces the brain to reconsider the picture and the object's relationships with one another.
Importance of Change Blindness
Given that change blindness is largely related to our cognitive limitations, it is unlikely that there will ever be a cure. Nevertheless, research remains important in order to mitigate the potentially dangerous outcomes.
Take, for example, a bus driver that drives the same route every day. They may be so focused on the road in front of them that they fail to notice that a small child has walked into the street fifteen feet ahead. The same can be said for piloting an airliner or any other activity that requires a person to be aware of their total surroundings.
Change blindness can have important implications for courtroom testimony as well. Imagine that a person testifies that they saw someone rob a bank and that the person was alone in committing the act. It is possible that because they were so focused on watching one individual, they missed the other two robbers who entered the bank shortly afterwards and assisted in the robbery.
Lesson Summary
Change blindness is a phenomenon in which a person fails to recognize changes to their environment or visual stimuli, despite their being very obvious. This can be seen in Daniel Simons' research in the 1990s, in which people missed the introduction of a gorilla into a basketball game due to what he calls inattentional blindness.
In many cases, this is caused by neurological limitations, but it also might be the result of attentional selection, which is when a person chooses a certain number of things to focus on, while other things are filtered out. Moreover, it is possible that things like age and health can be a factor, or something more subtle like object presentation.
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What Is Change Blindness?
Have you ever been so engrossed in a conversation at a party that you failed to notice that someone new is standing only six inches away from you, trying to get your attention? It's possible that you were so distracted that you didn't notice someone approaching you. But it's also entirely likely that you were experiencing change blindness.
Change blindness is a phenomenon that occurs when a person is unable to notice visual changes in their environment, despite the fact that they are often rather obvious. In cases of change blindness, the person isn't failing to notice small or insignificant changes, but will probably miss big changes, like someone standing next to them waving their hand.
Experiments
Early experiments with change blindness focused largely on memory and perception when viewing pictures. For example, a person might be shown a photograph of a street scene in Egypt and told to memorize the image. Following that, they would be shown the same picture with certain elements added or taken away and asked to identify what's different. Very often the individual could recall the larger aspects of the picture but couldn't recognize the smaller changes.
An inability to recognize every change in a crowded or complicated picture is generally attributed to the brain's capacity to remember complex images in a broad scope. For example, they might remember looking at a picture of a crowded street with stores and restaurants, but they probably wouldn't notice that the names of the stores had changed. In general, this is because the brain cannot possibly process every element of an experience and has to prioritize what it believes to be important.
Inattentional Blindness
In the 1990s, researcher Daniel Simons conducted a fascinating study into change blindness that many people find unbelievable. In Simons' study, he asked participants to watch a video of a basketball being passed around between several people, with a particular focus on the basketball itself. When the experiment was over, Simons found that a large number of participants were so focused on watching the basketball being passed around that they failed to notice a man in a gorilla suit jumping around in front of the camera.
It's important to note that the change in Simons' video wasn't subtle. The gorilla is very obviously taking up much of the frame. Simons concluded that participants were experiencing inattentional blindness, which is when a person fails to notice a major change because they are so focused on another task. In this case, because participants were asked to focus on the movement of the basketball, their brains prioritized that task in order to do it properly, thereby missing the other things happening in the video.
In the case of Simons' study, participants engaged what's referred to as attentional selection, which is when a person selects certain things to focus on in order to achieve a task and filters out anything that is unrelated to the objective.
Causes
There are a number of theories about what causes a person's inability to recognize obvious changes in their environment, but most agree that the phenomenon is related to sensory processing. Broadly speaking, our brains have a limited capacity to detect and process everything in our environment. Instead, what the brain does is choose certain things to process, evaluate, and store, which allows other things to be missed or filtered out.
In simple terms, change blindness has a great deal to do with where a person directs their attention. In the case of the gorilla and the basketball, people focused their attention almost exclusively on one thing, which caused them to miss other elements or changes. Given that attention is often at the root of change blindness, a person's age or mental and physical health can influence how well they will notice changes in stimuli.
Another important factor is object presentation, which is how objects or other visual stimuli are presented or introduced. For example, in experiments involving identifying changes in pictures, the brain can detect some of the major changes because they are obvious, but they might miss smaller ones that are hidden throughout the image. Moreover, a person is more likely to notice something being added to an image than something being taken away. Researchers believe that this is because adding something to an image forces the brain to reconsider the picture and the object's relationships with one another.
Importance of Change Blindness
Given that change blindness is largely related to our cognitive limitations, it is unlikely that there will ever be a cure. Nevertheless, research remains important in order to mitigate the potentially dangerous outcomes.
Take, for example, a bus driver that drives the same route every day. They may be so focused on the road in front of them that they fail to notice that a small child has walked into the street fifteen feet ahead. The same can be said for piloting an airliner or any other activity that requires a person to be aware of their total surroundings.
Change blindness can have important implications for courtroom testimony as well. Imagine that a person testifies that they saw someone rob a bank and that the person was alone in committing the act. It is possible that because they were so focused on watching one individual, they missed the other two robbers who entered the bank shortly afterwards and assisted in the robbery.
Lesson Summary
Change blindness is a phenomenon in which a person fails to recognize changes to their environment or visual stimuli, despite their being very obvious. This can be seen in Daniel Simons' research in the 1990s, in which people missed the introduction of a gorilla into a basketball game due to what he calls inattentional blindness.
In many cases, this is caused by neurological limitations, but it also might be the result of attentional selection, which is when a person chooses a certain number of things to focus on, while other things are filtered out. Moreover, it is possible that things like age and health can be a factor, or something more subtle like object presentation.
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What are the causes of change blindness?
Change blindness occurs because a person is unable to pay attention to everything around them at one time. Age, attention disorders, and drug use may influence someone's likelihood of experiencing change blindness.
What is a real life example of change blindness?
A kid's pet goldfish died one day while she was at school. Her parents replaced her fish with a similar fish, which had minor differences from the original one. The kid never noticed it was a different fish and thus experienced change blindness.
What is change blindness and why is it important?
Change blindness occurs when a person does not notice an otherwise noticeable change in something they observe. Change blindness is essential because individuals may miss critical changes in their surroundings (like a missing safety feature), resulting in severe consequences, including injury.
What is the difference between change blindness and inattentional blindness?
Change blindness occurs because individuals are unable to pay attention to every aspect of their surroundings. Inattentional blindness occurs when individuals focus heavily on a single thing, making them less aware of other events in their surroundings.
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