Divided attention, selective attention, inattentional blindness, & change blindness

all right I am going to start out with a challenge for you I'm going to show you a series of shapes and I want you to count the number of yellow stars that you see also count the number of red X's that pop up on the screen so that's two separate numbers 1 4 how many yellow stars you see and 1 4 how many red X's come up on the screen all right so that was probably a challenging task because you had to count two different things and I kept talking to you while you were trying to do that that's an example of divided attention which we'll talk about in just a second but first you probably want to see how you did so let me show you everything that you just saw alright this is everything that popped up on your screen there were 15 yellow stars and 13 red X's and also 1 smiley face don't worry if you didn't see this guy we'll talk about that later but now that you have a good example of how limited a resource your attention is let's talk more about it when you're paying attention to something that means that you're concentrating on it at the exclusion of the other stimuli and the environment a lot of times though we try to divide our attention and do multiple things at once so maybe watch TV while studying or try to count yellow stars while trying to count red X's the thing is as you just saw attention is a limited resource and we can't split it all that well when it comes to complicated stimuli so if you're trying to do two things at once usually end up switching between those tasks rather than doing them simultaneously even if you're switching so fast you can barely tell so think back to when you had to count the yellow stars and the red X's you couldn't really do that at the same time you had to kind of flip back and forth when you switch or if you do just intend to focus on one thing at a time you're exercising you're selective attention you can think of selective attention like a flashlight beam on some aspect of your environment you can move the flashlight around depending on what you want focus on but at any given moment it's illuminating one particular area of interest and everything else is just kind of dimmer so the question is what causes your flashlight beam to swing around and focus on one thing or another there are two types of cues that can direct our attention exogenous and endogenous exogenous to any goals we might have meaning we don't have to tell ourselves to look for them in order for them to capture our attention they include things like bright colors or loud noises because you can be in the middle of a gripping conversation and have every intention on focusing on it but a loud noise will still cause your focus to shift and with salient visual cues so ones that really stand out this is called the pop-out effect something just pops out at us like a yellow circle amidst a bunch of green circles endogenous cues on the other hand are more internalized and higher order meaning they involve internal knowledge to understand the cue in the first place and the intention to follow it take an arrow for example if you didn't know what an arrow meant then you wouldn't know to follow it is just some random lines on a piece of paper but because you have the internal knowledge of what an arrow is you can carry out an intention to look where it's pointing one really good example of selective attention is the cocktail party effect which you've probably experienced yourself multiple times and this is your ability to attend to one voice even amidst many others and it was commonly occurs when you hear your own name amid those voices so for example picture the last time you had a big family dinner and you're at one under the table talking with someone and then grandma down at the other end of the table says your name and even though you hadn't been listening to grandma's conversation you instantly swing your flashlight beam of attention down to hear what she is saying about you and if you had to guess what type of cue your name was in that situation and dodging Asur exogenous what would you say if you said endogenous then that's right because it was the meaning of your name that drew your attention and to win grandma said it alright so now we know that different cues draw our attention to certain stimuli whether we want them to or not but what happens to all the stuff were not paying attention to scarily enough we experience something called inattentional blindness which means that we're not consciously aware of things that happen in our visual field when our attention is directed elsewhere within that field so think back to that smiley face from our demo in the beginning because you are focused on yellow stars and red x's you might have missed the smiley face especially because he kind of blended in with the yellow stars and that's a minor example but inattentional blindness happens in more important situations too for example can you say exactly where the nearest fire extinguisher is if you're like most people you probably go by this every day when you're going to your home or office or wherever you are but very few people actually pay attention to where things like fire extinguishers are even though they're bright red they can be necessary for survival usually your attention is directed elsewhere if you fail to notice the fire extinguisher and closely related to inattentional blindness is change blindness which is when we fail to notice changes in the environment now be careful because the difference between change blindness and inattentional blindness is subtle but important inattentional blindness means that you miss something right in front of you while change blindness means that you fail to notice a difference between a previous state and a current state like when you don't notice when your mom gets a haircut or you get back to them and don't notice that furniture books are in a different place this is actually very common as well so don't feel bad if it happens to you in fact there's one really good example when a researcher stopped people on a busy street and asked for directions and partway through when the people were giving their directions a large bookcase was carried between them and the researcher and he swapped places with a different person and almost no one noticed and very few people even noticed when the new person was a different race or agender so it's just a great example of our limited attention and our ability to focus on one they to the exclusion of everything else