“Selective attention refers to the processes that allow an individual to select and focus on particular input for further processing while simultaneously suppressing irrelevant or distracting information.” (The role of selective attention on academic foundations; A cognitive neuroscience perspective.) To put things into less confusing terms;
Selective attention is when your brain is focused on a singular thing (Ex. cups moving around,) and it ignores any other information that it finds unimportant, (like something going on in the background, or an object being added/replaced.) Some good examples of this phenomenon can be found on youtube.
Now you may not think that selective attention happens in our everyday lives, but surprisingly, it does! Selective attention may happen more often than you think, and an example of this is like when you’re talking to your friend in a crowded area, you’re only trying to focus on their voice and what they’re saying and ignoring everything else around you. Another good example of this is when you’re completing a task and you’re very focused, someone goes and talks to you but you weren’t listening because you were focusing on your task. There are plenty of videos or examples of selective attention, there are even tests that you can take!
Now, how does this actually happen? Well the thing is, researchers have made tons of hypotheses about it, but no one knows exactly how it happens. According to “How Selective Attention Works,” “One of the earliest theories of attention was Donald Broadbent’s filter model. Building on the research conducted by Cherry, Broadbent used an information-processing metaphor to describe human attention. He suggested that our capacity to process information is limited in terms of capacity, and our selection of information to process takes place early on in the perceptual process.” This basically means that Broadbent came up with the theory that our ability to process information is limited, and that your brain just mentally deletes the unimportant information from your memory.
Another theory about how selective attention works is that instead of the filter that Broadbent was suggesting, it was more like an “attenuator,” or something that just muffles/reduces the amplitude of a certain thing. The article states- “Think of the attenuator like a volume control—you can turn down the volume of other sources of information in order to attend to a single source of information. The “volume” or intensity of those other stimuli might be low, but they are still present.” (How Selective Attention Works) In short, it doesn’t completely filter the information out, it just muffles it a bit, and makes it so that other information is more prominent. This theory was made by Anne Treisman.
To end this article off, some videos you can watch to experience this phenomenon for yourself are;