6.4 Attentional Blink: Definition & Experiment
What is Attentional Blink?
Have you ever tried to pay attention to multiple things at a time, only to find that you can’t focus completely on any of them? The mind has a limited capacity for attention. It sifts through large amounts of input so we can focus on what’s important and ignore distractions; however, some of these distractions may be important. For example, imagine that you’re driving down the street at rush hour, and notice that the driver in front of you has slammed on his brakes. A split-second later, while you are still busy processing what just happened, a deer darts onto the road from the right. At this point, it’s highly unlikely that you will be able to process the second event with enough time to react properly.
During that very short amount of time between one event and another, you have a ‘blind spot’ in your attention. This is known as the attentional blink, and it typically lasts for half a second. It’s as though you’re blinking your eyes and missing potentially critical information while your lids are closed. Let’s discuss an experiment that first allowed scientists to measure this phenomenon.
Attentional Blink Experiment
The term ‘attentional blink’ was first used by psychologists Raymond, Shapiro, and Arnell in 1992. In their first experiment, they presented letters and numbers to participants in a rapid succession of ten items per second in a method called rapid serial visual presentation (RSVP). In each series, all of the figures were black except for one white letter, and participants were asked to identify that letter. They were also asked whether they saw the black letter ‘X’ after the white letter appeared. The researchers called the white letter the ‘first target’ and the letter ‘X’ the ‘second target.’
The second target was only displayed half of the time. When it was shown, it appeared between 100 and 800 milliseconds (ms) after the first target. The researchers defined attentional blink as occurring when participants correctly identified the first target but incorrectly reported the second target after 100 to 500 ms, or up to half a second, of time passed between them.
Errors identifying the second target happened less as the time interval between targets increased. In other words, the closer together the targets appear, the more likely we are to experience an attentional blink. As follow ups, many other experiments have been conducted, in order to provide a better understanding of this phenomenon.
Let’s discuss some prominent theories used to explain what causes attentional blink.
What Causes Attentional Blink?
As we’ve just discussed, there’s a definitive procedure for measuring attentional blink. However, there’s still some debate about what causes this phenomenon, as demonstrated by the five theories below.
- Attentional capacity theory: This theory focuses on attention as a resource. It suggests that target one will take up precious attentional resources, making it difficult to process target two for up to half a second.
- Inhibition theory: According to the inhibition theory, when detecting the first target, the mind focuses on identifying information, such as the target’s color and shape, or whether it is a letter or number. For about half a second afterward, your mind suppresses incoming information to prevent confusion. In other words, the attentional blink occurs during the time you’re thinking about what you’ve seen.
- Delay of processing theory: This theory suggests that when you’re busy thinking about target one, you essentially ‘forget’ about target two.
- Interference theory: As stated in the interference theory, items shown in a series are competing with each other in your limited working memory. Therefore, confusion can occur when you try to recall what you saw.
- Two-stage processing theory: According to this theory, there are two stages involved in processing a series of items. The rapid-detection stage occurs when you’re quickly analyzing items for the features you’re seeking. In order to prevent decay in your working memory, you transfer the features to the capacity-limited stage, where deeper processing occurs. However, your mind can only process one thing at a time during this stage. If target two appears while you’re still in stage one, the target remains in this stage, where it is vulnerable to interference by other items for about half a second.
While all of these theories are supported by experiments, the support depends on the specific procedures used. However, researchers do agree that attentional blink can have real-world consequences, like in our hypothetical driving situation. Interestingly, one study showed that attentional blink can be reduced in duration by ‘training’ our brains. Researchers also found that people who played fast-paced video games had a quicker attentional blink recovery than those who played puzzle games. The need to quickly identify and eliminate one target after another provided incentive for the brain to reduce attentional blink.
Attentional blink is a half-second of perceptual impairment that occurs between one stimulus and another. In experiments, it is typically measured using the rapid serial visual presentation (RSVP) method. Many theories have been proposed to explain this phenomenon, including those related to delay of processing, interference, and two-stage processing. The attention capacity theory in particular states that target one will take up precious attentional resources, making it difficult to process target two for up to half a second. By comparison, the inhibition theory suggests that when we detect an initial target, our focus will be on its identifying information, during which time, we’ll suppress other incoming information to avoid confusing ourselves.