Understanding Attention in Cognitive Ergonomics

Hello everyone and in today's lecture we talk about attention. So attention is a very important component when it comes to cognitive ergonomics. In the prior lecture on the visual system we discussed the composition of the retina with cones being more prevalent in the center and having a higher sensitivity to colors and movement. If you remember we also briefly discussed the implication that that structure of the retina has for attention. Usually when we pay attention to something we try to have that object that we pay attention to in the center of our visual field. So the information that is processed by cones is usually the information that we pay attention to. So we're still sensitive to information in the periphery of the visual field, not only from not only for the visual system but also the auditory system if you think about it. Like we talked in the prior lecture about the cocktail party effect, something that we'll touch upon again in this lecture. If there is a very salient sound, like your name being called out loud, even if in a very busy room, you're still able to not only perceive it, but your attention is immediately directed to that source of sound. By the same token, in the visual system, if there is an object that is very salient appearing in the periphery of the visual field, like an object that is moving, fast pace or a very bright object or you know very bright color even if that object is not falling in the center of the visual field but because of its characteristics we're immediately drawn to that source of information so we immediately you know start paying attention to it So when we talk about attention, there are usually several types, if you like, of attention. Selective attention is one of them. This is the ability to select information that is salient to us, that is relevant to us, and ignore what is not relevant. We talked about then, we'll talk about models of selecting attentions and also executive functions. Executive function is the ability to, you can think of executive function as a attention manager in the sense that, because there's a lot of information in the outside world that is competing for our attention. we have to strategically decide what to pay attention to and what to ignore. So executive functions help us manage our attention between all the sources competing for it. At the very end we'll discuss some neuropsychology of executive functions. So to start off with what is the role of attention in human factors and ergonomics? Because our attention is limited, we can only pay attention to so much information. But also attention is very key to completing tasks, jobs efficiently and safely. Understanding how attention works is important to ensure that whenever we complete manufacturing tasks, healthcare tasks, driving tasks, we use computers, cell phones or any other device that our attention is properly directed to the task at hand. However, this opens up the issue of paying attention to something that is not relevant to the task at hand. A clear example is driving. with you know driver distraction but the same situation applies to healthcare for instance where as I mentioned the prior lecture healthcare practitioners they're sort of bombarded with information from all of these systems and it's key for them to maintain attention to you know what really matters which is the well-being and the safety of their patients. But with so many information begging for their attention it becomes very difficult to pay attention to what's important and what's not or what's less important anyway. There was a recent article from a couple of years ago I believe Navy ditches touchscreen for knobs and dials after fatal crash. There was, at one point the Navy decided to move away from touchscreen for their systems and instead go back to traditional analog controls like knobs and dials. Because at one point there was a crash, the thing was a ship. crashed into another ship if I remember correctly and one of the factors contributing to that crash was you know has to do with the design of the touchscreen and how ineffective it was potentially distracting it was relative to you know analog controls another field where you know attention is very important is manufacturing especially in situations where manufacturing jobs are repeated. In automotive manufacturing, for those of you who have worked or interned at an assembly plant, the same job is repeated every minute or so. So at that point it's really important to maintain attention, to sustain attention over time. And one problem that may result from sustained attention is sort of getting bored and lacking vigilance over time. So really attention plays a very important role in all aspects of our lives and of course in cognitive ergonomics as well. In the research that we do in the Human Systems Lab, we do investigate the role that attention plays in assembly work performance, assembly task performance. In a recent study, we had workers complete manufacturing type of tasks in two scenarios. In one, they just completed the manufacturing task, and in the other one, they were... had to do all tasks. So there was a mental task that were required to perform. And what we saw was that the completion times for the task at hand, it took approximately 50 seconds for that job to complete in the control condition, but when the cognitive workload increased, it took for certain participants double that time. A similar effect was found on muscle activity. So whenever the secondary task, the dual task was introduced, we saw an increase in EMG activity for certain muscles. This could have been the result of user getting frustrated with the secondary task and mis-managing or mis-calibrating the amount of muscle activity that is required. exertion that was required to complete the task. But interestingly is that whenever we have conditions where the worker in this case is struggling to divide attention toward the task at hand, not only we see a drop in performance in this case in completion times, but also we see consequences for physical factors. So when we talk about selective attention, oftentimes the analogy that comes to mind is that of a lens. So whatever falls in the center of, let's say a lens like a magnifying glass, whatever falls in the center of the magnifying glass, we pay attention to. but whatever is in the periphery it's not it's like blurry looks blurry and it's something that we don't pay attention to so when it comes to attention i said there are different types of attentions if you like selective executive function divided as sustained attention Selective attention is the ability to select task relevant information and ignore irrelevant information. So if you're trying to pay attention to this video, this lecture, and then you have your phone ringing or noise coming from the street, you're using your selective attention to pay attention to this lecture and ignore what's not. not relevant. Interestingly the study on selective attention started in the mid 1900s and it is fairly common not only for cognitive science but also for human factors. A lot of funding for a lot of what we know in cognitive science neuroscience and human factors comes out of military funding so starting in the early to mid 1900s especially the u.s department of defense they started funding research in psychology cognition neuroscience to better understand how the mind of military personnel worked and how to improve from the human factor side how improve the interaction between military personnel and airplanes like fighter planes or any other defense machine and so to make them more effective at their job is that how you know they started like funding research in this field so you start digging into the field of cognitive science, neuroscience, and human factors, you will see that a lot of the seminal work in this area was done around the turn of the mid-1900s. Cherry in 1953 developed this dichotic listening paradigm to investigate selective attention. In this case, the participant is wearing a headset, there are two messages being provided, one in the left ear and one in the right ear. In this case, the one in the right ear of the participant, the horses galloped across the field, there was the message that participants were told to ignore. So they were told not to attend to this information, not to pay attention to it. There was other source of information being presented in this participant's left ear, which was President Lincoln of the Red by the Light of the Fire. And so what they had to do, not only ignore the other message, but they had to pay attention to this message, the relevant message, and also had to repeat it. So like shadowing. Participants were successful at ignoring the message they were told to ignore and repeating the message they were told to pay attention to. So broadband is a seminal pioneering figure in the study of attention. So it's thought of attention like a filter. We experience a lot of sensory information in our environment from visual information, auditory information, etc. So in broadband to envision attention like a filter. So the sensory information comes into the system and then there is a filter that decides what makes it through the filter and what's not. So information is not relevant like in this example information about horses. According to this model broadband's model is doesn't make it through the filter. on the other hand information is relevant in this case the information about president lincoln makes it through the filter at that point some information only the information that gets make it through the filter gets processed and the information that doesn't make it through it gets ignored i mentioned to you this already um it's you know the cocktail party effect So in that case, there is a video here. Let's see if we can. What is the cocktail party effect? It's this phenomenon where in the midst of a noisy cocktail party, any kind of noisy sporting event or newsroom, we're still able to focus in on the one conversation we want to hear. here and somehow tune out everything else. And how can, now researchers, neuroscientists are very interested in this. Why is that? Why do they want to know where this ability comes from? It's part of this whole phenomenon of selective attention wherein the human brain can only really focus in intensely on one thing at a time. And this is a survival skill. You know, we're constantly bombarded by all this visual and auditory stimulation. We couldn't survive unless we could focus in like this. But we can also only really focus on one thing at a time. And that's what's at issue in distracted driving and all kinds of other limitations of multitasking. Are there people who, is there a small percentage of people who actually have sort of a super ability to focus on more than one thing? Or is that? Is that a myth? Yes. Researchers at the University of Utah have found some of these people in the course of their other research. They think it's about 2% of the population. The real problem is that most of us think we can do that, and that can have some disastrous consequences. and even if you're talking to somebody or have a completely different task, you're still able to pay attention to hear that sound and pay attention to it. Now from this perspective, that represents criticism to broadband's model, because broadband says that attention is a filter, so we can consciously decide what to pay attention to and what to ignore. So if that, if broadband's model was true, then if somebody calls for us in the middle of a noisy room, if that's something that we don't want to pay attention to, that information shouldn't get through to us and us paying attention to it. So attention then may not work like a filter in the sense that what we want to pay attention to goes through the filter and what we don't want to pay attention to it gets ignored. So because of this evidence of the cocktail party effect showing that you know even if it's a noise or sound that we don't pay we don't want to pay attention to it's not something that you know it's relevant because we're paying attention perhaps to having a conversation with our you know with somebody at the cocktail party steal them information that sound makes it through. and draw their attention in. So why is that? Moray in 1959 said that we can ignore high level semantic information of the unattended message, like we saw in Cherry's dichotic listening model. But even if that's the case, from time to time there are very salient information is presented to us like our names It's very salient. And so even if we decide not to pay attention to the noise surrounding us information like that when it's presented to us we automatically direct our attention to like the The researcher in the video that we just watched, the lady on the left mentioned that selective attention is a survival mechanism. Whenever we're presented, whenever we hear our name, you know, that means that is something that, you know, may be highly relevant to us. You know, somebody calling our name, you know, they want something from us, they're demanding our attention. So it must be, you know, it's likely to be something very important. So that's why our name in that case is such a you know that phonemes together is such a salient source of information that even though we're not paying attention to it at first whenever we hear it our attention is automatically directed to it So, in this study from 2006, Carmody and Lewis find that hearing our names activates specific areas of the brain that are not activated following the presentations of other names. So it's not just a matter of any names, you know, my names, my friends'names, etc. But there is something in our brain that is activated only when our own name is presented to us. So going back to Broadband's model. then the cocktail party effect sort of negates the broadband model. Because if we're really able to ignore information consciously, so everything that we don't want to pay attention to, we just ignore, there wouldn't be such a thing as a cocktail party effect. So attention then must not work as a filter that we can decide what to keep out of the filter and what to let in. So in 1960, Treisman formulates a variation to Broadbent's model. And in this model, attention is not seen as a filter, like a non-off filter, but more of an attenuator. So what does that mean? Think about the switch. So broadband model, so attention, like selective attention switch, is there on or off on certain information. In Triesmann's model, attention is sort of like as a gradient from being fully off to being fully on. So according to this model, even non-attended messages, so information that is not relevant to us, can still make it through to our attention if the characteristics of that information makes that information salient enough. So messages there have certain physical characteristics, for instance very loud noises if you're in your room and there is an ambulance going by even though you don't. intend to pay attention to the ambulance but the siren is so loud that you can't ignore it. Language, words and syllables, certain words, certain syllables, they're more familiar to us. they're more salient and as a result of that, like for our names, we just pay attention to it. Or in a certain case, the meaning of the message, that if something that is salient to us for whatever reason, these messages get powered up, if you like. So relevant information is amplified, but again, depending on these characteristics even information that is not relevant to us still may still make it through um so the with the last unit the last what's a dictionary unit in this model it uh that's the unit is about what you know how um why explain the mechanism by which certain words they received, they get a boost in activation, certain words do not. So, and this mechanism that the model is using is called activation thresholds. So some words have different activation thresholds depending on their meaning. Words with low thresholds, like our own name, are activated faster than those with high thresholds. So imagine that, for instance, in this case, hypothetically, you have a threshold of activation. so activation threshold so in order for that word to be detected by you to pay attention to it the activation that each word receives has to be higher than in this threshold everything that is below the threshold here is not activated So certain words like, say for instance, many words like for instance, if we take a word like dog, that's a word that we are, it's very familiar to us, but it's not our own name. So it's not something very salient. Okay, so the activation threshold may be set to this level. There may be other words on the other hand they have a lower activation threat, sorry they have a lower activation, something very uncommon like torque. So torque is, most people are less familiar with the word torque than they are with the word dog. So the activation associated with this word is much lower. On the other hand, if we take our own name, that word may have a much higher activation level. So in that case, if this is the activation threshold, the dashed line, if we hear the word torque, the word torque has to be spoken really loudly for this word. to reach and the activation threshold. By the same token, words that already have a high level of activation, they don't need to be spoken very loudly. So the difference between the for the for the torque for instance, the difference between their activation and the is very large. But for our own name there may be just a slight difference. So words like our own name just need to be spoken not as loudly in order for us to pay attention to them. There may be other words like dog where the activation that is required to go over that threshold is not as much as unfamiliar or uncommon words like Tark, Turk, but by the same token it's more than the level of activation that So processing capacity is the amount of information we can process at any time. So when I say that our cognitive system is limited, that means that we do not have unlimited attentional capacity. We can only pay attention to so much. In the video that we watched before, the lady on the left said that we can only pay attention to one thing at a time. So our attentional capacity is limited and we cannot pay attention to more than one thing at a time. So the analogy they like using to describe attentional capacity is that of a water bottle. So if you have a bottle of water. there's only so much water, you know, an empty bottle, there's only so much water that goes into there, that can go into it. You can put more water than the bottle can hold, but at one point, when the capacity is reached, the water is going to spill out of the bottle. What also variable is also the capacity, how big that bottle is. If we are, you know, just woke up or in the morning, if you're a morning person, it may be that you have higher capacity in the morning. So some of you may prefer, you know, to study in the morning, some of you may prefer to study in the evening, so it's just a personal preference. But you feel like there are times during the day where you... are better at studying or memorizing information. So at that time the capacity of your bottle may be higher. There are other times during the day, for example during the year, where your capacity is reduced, maybe because you're tired or for whatever other reason, but even if it's you always the same person, But the capacity of the water bottle may change. It's bigger under certain circumstances, and the capacity also can become much smaller under different circumstances. So factors like fatigue, time of the day, number of tasks being performed, stress levels, can have an effect on how... much capacity that bottle can you know has the other component to this you know model of the water bottle is the task demand so you may feel like take a task like counting backwards by seven you may be able to perform that task you know relatively easily or more easily at certain times of the day. So whenever your capacity is greater, you're better off performing this task of counting backwards by seven from 100. On the other hand, there may be other times during the day, other under certain circumstances, where the same task may be more difficult. So, Then there are two components to this. One is the size of your capacity, the other one is how demanding is the task. Here's an example. If we keep the capacity of the bottle as a constant, here on the left side and the right side, the capacity of this jug is the same. wrong example. So let's say that this is the size of the water bottle when you have greater capacity and this is the size of the water bottle when you have less capacity. And these in blue, so here in red we have capacity and in blue we have task demand so a simple task or maybe like a you know like a task that we said like counting backward by seven from 100 is something that we're you know we can manage to do and it's gonna take like half of our capacity but you know half of our capacity when we our capacity is much greater is not going to be a difficult task to handle but when our capacity is reduced you know the blue water here he's gonna fill up the bottle and water is gonna spill out. So what I mean by that is even if we keep the task, you know, the counting backward by seven constant, but depending on how much capacity we have, we can either handle that task easily or that task can turn impossible to us. But the same token, whenever you know we have high capacity if a task is very difficult we put more water in the bottle that task is gonna you know take up a lot of room a lot of our capacity but it same take a token a simple task is gonna just take like a smaller amount of capacity so task demand depends on the difficulty of the task or simple tasks simpler tasks as associated with less demand an easy task imposes little demand and a difficult task imposes more demand task demand can be cognitive you know counting backward by one or by seven perceptual um if i ask you to count um how many you know the number of petals a flower has If it's a small flower, you only have a small amount of petals, but if the petals are smaller and it's a bigger field of flowers, that's going to be more challenging. Or more difficult. If I ask you to push a button every time you hear a bell, versus I ask you to press... 10 different keys on your keyboard in a random order when you hear a bell. Of course, both tasks require a motor response, but in the former case it's much easier than in the latter. So task demand can be cognitive perceptual motor or a combination of the three. So to sum it up, task performance is dependent on the amount of the capacity plus the demand associated with the task. Changes in one or both factors will affect the overall load imposed on the person, operator, users. So going back to attention, if say we're driving our car in the morning after a nice sleep, we can easily pay attention to driving and listening to an audio book. But maybe on the way back at night, even listening to an audiobook or having a conversation with the passenger, that's something too much for us to handle in addition to driving. A task that is commonly used, a paradigm that is commonly used for test selective attention is the spruik task. So some of you may already be familiar with this task. but how it works is they let the words be presented. In this case, you see the word red and the color it is presented is green. So the task for the participant, whenever they are presented with this word, is to say aloud the color of the ink. so in this case the response would be green in this case the response would be blue because the the color of the ink is blue in this case would be yellow red blue there are certain conditions we call congruent let me see yeah so there are some conditions that are called congruent where the color of ink matches the word so if you see a word you know yellow in yellow that's a congruent condition in this case on the other hand is incongruent in that the word is yellow but the code the ink is blue so this task has used commonly to measure selective attention. So whenever the two information, the color and the word match up, the participants are much faster at responding to producing the correct answer. On the other hand, whenever the condition is incongruent, so the color doesn't match the word, participants are much slower and they're the accuracy goes down. So this type of task is informative because it provides information how we process information you know attentively in our surrounding environment. These are some alternatives to the Stroop test for instance not that relevant. So In particular, this type of task is important because it tells us about our inhibitory control. In the congruent situation where the color and the word match, we have that automatic response in producing the response and that response is much faster and much more accurate. On the other hand, whenever we see an incongruent situation we have to inhibit our response for instance just to give you an example if you see in this situation where the color is blue and the word is blue our response will be blue okay so in this in this case you know we're much fast faster but in a different situation where the word is blue but the color is red we have these response of seeing red okay because our attention is really automatically directed to the color of the word not to the word itself. The color of the word is much easier to process than the semantics of the word. Okay, so in this case you see a blue in blue the first information that sort of activates our attention you know that passes that threshold that we talked about prior is the color blue. On the other hand here the you know because the color reaches that threshold much faster our automatic response would be red okay but red in this case it would be the incorrect answer the correct answer would be blue because that's you know the word so in that case we have to inhibit that the color and try to pay attention to the word itself So that's what executive functions do. Executive function, again, as I said earlier, you can think of it as an attentional manager. Control attention, dealing with conflicting responses. In the case of the Stroop task, there are two sorts of information. One is task relevant, which is the word itself, and one that is not task relevant, which is the color of the word. So we need to inhibit the sort of attend with the information, the color information, that we automatically pay attention to. So we need to inhibit that response and instead pay more attention to what's task-relevant. So that's something that executive functions do. So they control attentional control, cognitive inhibition, and working memory. The neuropsychological evidence show that These executive functions are usually located the prefrontal cortex. There's a lot of work studies and case studies being done in executive function especially with clinical populations. Damaged or you know yeah damaged like the frontal cortex has been you know and so ineffective executive functions it's been associated with problems in planning, organizing, prioritizing. Think about again the amount of information that is present in your in the room that you're in even if it's a quiet room but you have the video to pay attention to you may also have your you know somebody in the other room making noises a noise coming from the street etc your phone somebody texting you so there's a lot even in such a quiet environment there's a lot of information that competes for your attention let alone in a much more active environment if you're driving you have to pay attention to the street, to the weather, to the other cars, to if you're driving in a residential area, to pedestrians, to animals. So in that case having our executive functions working properly it's necessary for our survivals and for our safety. So having executive functions damaged It's really, without exaggerating, like a life and death kind of situation. Lack of attentional flexibility, impaired concept formation. These are consequences of poor executive functions. Inability to monitor and adapt behavior consistent with social circumstances. You may be familiar with Tourette's syndrome and in that case Tourette's syndrome is associated with ineffective functioning of deficit to the executive functions. So patients with this condition, they tend to utter words that they're not maybe out of place. And this is because they have troubles inhibiting their thoughts. So whatever thoughts come to mind, they sort of, you know, there's no filter. You know, there's less of a filter. And so they end up adding words that, again, they're out of place. Evidence also showed that adults with autistic spectrum disorder have been shown impairment in certain executive functions, like understanding others'state of mind. I mean, state of mind is the ability to understand the other people's state of mind. So if you're talking to somebody and that person is showed distress in a normal individual, normal individual should be able to pick up on those clues. But on the other hand, there are certain clinical populations that they lack that. ability. In this figure here, if you compare just visually the red areas in the control group, subject without autism, and the autistic group, you will see that these are areas that receive activation. They are much smaller in the autistic group than in the normal control group. So this is it for this lecture. Again, in the next lecture we'll continue our discussion of attention and in particular instead of talking about selective attention like we did today, we'll talk about divided attention and sustained attention. So that's it for today. I will rest your day. Bye.

So the information that is processed by cones is usually the information that we pay attention to. So we're still sensitive to information in the periphery of the visual field, not only from not only for the visual system but also the auditory system if you think about it. Like we talked in the prior lecture about the cocktail party effect, something that we'll touch upon again in this lecture.

If there is a very salient sound, like your name being called out loud, even if in a very busy room, you're still able to not only perceive it, but your attention is immediately directed to that source of sound. By the same token, in the visual system, if there is an object that is very salient appearing in the periphery of the visual field, like an object that is moving, fast pace or a very bright object or you know very bright color even if that object is not falling in the center of the visual field but because of its characteristics we're immediately drawn to that source of information so we immediately you know start paying attention to it So when we talk about attention, there are usually several types, if you like, of attention. Selective attention is one of them.

This is the ability to select information that is salient to us, that is relevant to us, and ignore what is not relevant. We talked about then, we'll talk about models of selecting attentions and also executive functions. Executive function is the ability to, you can think of executive function as a attention manager in the sense that, because there's a lot of information in the outside world that is competing for our attention.

we have to strategically decide what to pay attention to and what to ignore. So executive functions help us manage our attention between all the sources competing for it. At the very end we'll discuss some neuropsychology of executive functions. So to start off with what is the role of attention in human factors and ergonomics?

Because our attention is limited, we can only pay attention to so much information. But also attention is very key to completing tasks, jobs efficiently and safely. Understanding how attention works is important to ensure that whenever we complete manufacturing tasks, healthcare tasks, driving tasks, we use computers, cell phones or any other device that our attention is properly directed to the task at hand. However, this opens up the issue of paying attention to something that is not relevant to the task at hand.

A clear example is driving. with you know driver distraction but the same situation applies to healthcare for instance where as I mentioned the prior lecture healthcare practitioners they're sort of bombarded with information from all of these systems and it's key for them to maintain attention to you know what really matters which is the well-being and the safety of their patients. But with so many information begging for their attention it becomes very difficult to pay attention to what's important and what's not or what's less important anyway. There was a recent article from a couple of years ago I believe Navy ditches touchscreen for knobs and dials after fatal crash.

There was, at one point the Navy decided to move away from touchscreen for their systems and instead go back to traditional analog controls like knobs and dials. Because at one point there was a crash, the thing was a ship. crashed into another ship if I remember correctly and one of the factors contributing to that crash was you know has to do with the design of the touchscreen and how ineffective it was potentially distracting it was relative to you know analog controls another field where you know attention is very important is manufacturing especially in situations where manufacturing jobs are repeated. In automotive manufacturing, for those of you who have worked or interned at an assembly plant, the same job is repeated every minute or so. So at that point it's really important to maintain attention, to sustain attention over time.

And one problem that may result from sustained attention is sort of getting bored and lacking vigilance over time. So really attention plays a very important role in all aspects of our lives and of course in cognitive ergonomics as well. In the research that we do in the Human Systems Lab, we do investigate the role that attention plays in assembly work performance, assembly task performance.

In a recent study, we had workers complete manufacturing type of tasks in two scenarios. In one, they just completed the manufacturing task, and in the other one, they were... had to do all tasks.

So there was a mental task that were required to perform. And what we saw was that the completion times for the task at hand, it took approximately 50 seconds for that job to complete in the control condition, but when the cognitive workload increased, it took for certain participants double that time. A similar effect was found on muscle activity. So whenever the secondary task, the dual task was introduced, we saw an increase in EMG activity for certain muscles. This could have been the result of user getting frustrated with the secondary task and mis-managing or mis-calibrating the amount of muscle activity that is required.

exertion that was required to complete the task. But interestingly is that whenever we have conditions where the worker in this case is struggling to divide attention toward the task at hand, not only we see a drop in performance in this case in completion times, but also we see consequences for physical factors. So when we talk about selective attention, oftentimes the analogy that comes to mind is that of a lens.

So whatever falls in the center of, let's say a lens like a magnifying glass, whatever falls in the center of the magnifying glass, we pay attention to. but whatever is in the periphery it's not it's like blurry looks blurry and it's something that we don't pay attention to so when it comes to attention i said there are different types of attentions if you like selective executive function divided as sustained attention Selective attention is the ability to select task relevant information and ignore irrelevant information. So if you're trying to pay attention to this video, this lecture, and then you have your phone ringing or noise coming from the street, you're using your selective attention to pay attention to this lecture and ignore what's not.

not relevant. Interestingly the study on selective attention started in the mid 1900s and it is fairly common not only for cognitive science but also for human factors. A lot of funding for a lot of what we know in cognitive science neuroscience and human factors comes out of military funding so starting in the early to mid 1900s especially the u.s department of defense they started funding research in psychology cognition neuroscience to better understand how the mind of military personnel worked and how to improve from the human factor side how improve the interaction between military personnel and airplanes like fighter planes or any other defense machine and so to make them more effective at their job is that how you know they started like funding research in this field so you start digging into the field of cognitive science, neuroscience, and human factors, you will see that a lot of the seminal work in this area was done around the turn of the mid-1900s. Cherry in 1953 developed this dichotic listening paradigm to investigate selective attention.

In this case, the participant is wearing a headset, there are two messages being provided, one in the left ear and one in the right ear. In this case, the one in the right ear of the participant, the horses galloped across the field, there was the message that participants were told to ignore. So they were told not to attend to this information, not to pay attention to it. There was other source of information being presented in this participant's left ear, which was President Lincoln of the Red by the Light of the Fire. And so what they had to do, not only ignore the other message, but they had to pay attention to this message, the relevant message, and also had to repeat it.

So like shadowing. Participants were successful at ignoring the message they were told to ignore and repeating the message they were told to pay attention to. So broadband is a seminal pioneering figure in the study of attention. So it's thought of attention like a filter.

We experience a lot of sensory information in our environment from visual information, auditory information, etc. So in broadband to envision attention like a filter. So the sensory information comes into the system and then there is a filter that decides what makes it through the filter and what's not.

So information is not relevant like in this example information about horses. According to this model broadband's model is doesn't make it through the filter. on the other hand information is relevant in this case the information about president lincoln makes it through the filter at that point some information only the information that gets make it through the filter gets processed and the information that doesn't make it through it gets ignored i mentioned to you this already um it's you know the cocktail party effect So in that case, there is a video here.

Let's see if we can. What is the cocktail party effect? It's this phenomenon where in the midst of a noisy cocktail party, any kind of noisy sporting event or newsroom, we're still able to focus in on the one conversation we want to hear. here and somehow tune out everything else. And how can, now researchers, neuroscientists are very interested in this.

Why is that? Why do they want to know where this ability comes from? It's part of this whole phenomenon of selective attention wherein the human brain can only really focus in intensely on one thing at a time.

And this is a survival skill. You know, we're constantly bombarded by all this visual and auditory stimulation. We couldn't survive unless we could focus in like this.

But we can also only really focus on one thing at a time. And that's what's at issue in distracted driving and all kinds of other limitations of multitasking. Are there people who, is there a small percentage of people who actually have sort of a super ability to focus on more than one thing? Or is that?

Is that a myth? Yes. Researchers at the University of Utah have found some of these people in the course of their other research.

They think it's about 2% of the population. The real problem is that most of us think we can do that, and that can have some disastrous consequences. and even if you're talking to somebody or have a completely different task, you're still able to pay attention to hear that sound and pay attention to it. Now from this perspective, that represents criticism to broadband's model, because broadband says that attention is a filter, so we can consciously decide what to pay attention to and what to ignore.

So if that, if broadband's model was true, then if somebody calls for us in the middle of a noisy room, if that's something that we don't want to pay attention to, that information shouldn't get through to us and us paying attention to it. So attention then may not work like a filter in the sense that what we want to pay attention to goes through the filter and what we don't want to pay attention to it gets ignored. So because of this evidence of the cocktail party effect showing that you know even if it's a noise or sound that we don't pay we don't want to pay attention to it's not something that you know it's relevant because we're paying attention perhaps to having a conversation with our you know with somebody at the cocktail party steal them information that sound makes it through.

and draw their attention in. So why is that? Moray in 1959 said that we can ignore high level semantic information of the unattended message, like we saw in Cherry's dichotic listening model. But even if that's the case, from time to time there are very salient information is presented to us like our names It's very salient. And so even if we decide not to pay attention to the noise surrounding us information like that when it's presented to us we automatically direct our attention to like the The researcher in the video that we just watched, the lady on the left mentioned that selective attention is a survival mechanism.

Whenever we're presented, whenever we hear our name, you know, that means that is something that, you know, may be highly relevant to us. You know, somebody calling our name, you know, they want something from us, they're demanding our attention. So it must be, you know, it's likely to be something very important.

So that's why our name in that case is such a you know that phonemes together is such a salient source of information that even though we're not paying attention to it at first whenever we hear it our attention is automatically directed to it So, in this study from 2006, Carmody and Lewis find that hearing our names activates specific areas of the brain that are not activated following the presentations of other names. So it's not just a matter of any names, you know, my names, my friends'names, etc. But there is something in our brain that is activated only when our own name is presented to us. So going back to Broadband's model. then the cocktail party effect sort of negates the broadband model.

Because if we're really able to ignore information consciously, so everything that we don't want to pay attention to, we just ignore, there wouldn't be such a thing as a cocktail party effect. So attention then must not work as a filter that we can decide what to keep out of the filter and what to let in. So in 1960, Treisman formulates a variation to Broadbent's model. And in this model, attention is not seen as a filter, like a non-off filter, but more of an attenuator.

So what does that mean? Think about the switch. So broadband model, so attention, like selective attention switch, is there on or off on certain information. In Triesmann's model, attention is sort of like as a gradient from being fully off to being fully on. So according to this model, even non-attended messages, so information that is not relevant to us, can still make it through to our attention if the characteristics of that information makes that information salient enough.

So messages there have certain physical characteristics, for instance very loud noises if you're in your room and there is an ambulance going by even though you don't. intend to pay attention to the ambulance but the siren is so loud that you can't ignore it. Language, words and syllables, certain words, certain syllables, they're more familiar to us. they're more salient and as a result of that, like for our names, we just pay attention to it.

Or in a certain case, the meaning of the message, that if something that is salient to us for whatever reason, these messages get powered up, if you like. So relevant information is amplified, but again, depending on these characteristics even information that is not relevant to us still may still make it through um so the with the last unit the last what's a dictionary unit in this model it uh that's the unit is about what you know how um why explain the mechanism by which certain words they received, they get a boost in activation, certain words do not. So, and this mechanism that the model is using is called activation thresholds.

So some words have different activation thresholds depending on their meaning. Words with low thresholds, like our own name, are activated faster than those with high thresholds. So imagine that, for instance, in this case, hypothetically, you have a threshold of activation.

so activation threshold so in order for that word to be detected by you to pay attention to it the activation that each word receives has to be higher than in this threshold everything that is below the threshold here is not activated So certain words like, say for instance, many words like for instance, if we take a word like dog, that's a word that we are, it's very familiar to us, but it's not our own name. So it's not something very salient. Okay, so the activation threshold may be set to this level. There may be other words on the other hand they have a lower activation threat, sorry they have a lower activation, something very uncommon like torque.

So torque is, most people are less familiar with the word torque than they are with the word dog. So the activation associated with this word is much lower. On the other hand, if we take our own name, that word may have a much higher activation level.

So in that case, if this is the activation threshold, the dashed line, if we hear the word torque, the word torque has to be spoken really loudly for this word. to reach and the activation threshold. By the same token, words that already have a high level of activation, they don't need to be spoken very loudly. So the difference between the for the for the torque for instance, the difference between their activation and the is very large.

But for our own name there may be just a slight difference. So words like our own name just need to be spoken not as loudly in order for us to pay attention to them. There may be other words like dog where the activation that is required to go over that threshold is not as much as unfamiliar or uncommon words like Tark, Turk, but by the same token it's more than the level of activation that So processing capacity is the amount of information we can process at any time. So when I say that our cognitive system is limited, that means that we do not have unlimited attentional capacity. We can only pay attention to so much.

In the video that we watched before, the lady on the left said that we can only pay attention to one thing at a time. So our attentional capacity is limited and we cannot pay attention to more than one thing at a time. So the analogy they like using to describe attentional capacity is that of a water bottle. So if you have a bottle of water. there's only so much water, you know, an empty bottle, there's only so much water that goes into there, that can go into it.

You can put more water than the bottle can hold, but at one point, when the capacity is reached, the water is going to spill out of the bottle. What also variable is also the capacity, how big that bottle is. If we are, you know, just woke up or in the morning, if you're a morning person, it may be that you have higher capacity in the morning. So some of you may prefer, you know, to study in the morning, some of you may prefer to study in the evening, so it's just a personal preference.

But you feel like there are times during the day where you... are better at studying or memorizing information. So at that time the capacity of your bottle may be higher. There are other times during the day, for example during the year, where your capacity is reduced, maybe because you're tired or for whatever other reason, but even if it's you always the same person, But the capacity of the water bottle may change.

It's bigger under certain circumstances, and the capacity also can become much smaller under different circumstances. So factors like fatigue, time of the day, number of tasks being performed, stress levels, can have an effect on how... much capacity that bottle can you know has the other component to this you know model of the water bottle is the task demand so you may feel like take a task like counting backwards by seven you may be able to perform that task you know relatively easily or more easily at certain times of the day.

So whenever your capacity is greater, you're better off performing this task of counting backwards by seven from 100. On the other hand, there may be other times during the day, other under certain circumstances, where the same task may be more difficult. So, Then there are two components to this. One is the size of your capacity, the other one is how demanding is the task.

Here's an example. If we keep the capacity of the bottle as a constant, here on the left side and the right side, the capacity of this jug is the same. wrong example. So let's say that this is the size of the water bottle when you have greater capacity and this is the size of the water bottle when you have less capacity. And these in blue, so here in red we have capacity and in blue we have task demand so a simple task or maybe like a you know like a task that we said like counting backward by seven from 100 is something that we're you know we can manage to do and it's gonna take like half of our capacity but you know half of our capacity when we our capacity is much greater is not going to be a difficult task to handle but when our capacity is reduced you know the blue water here he's gonna fill up the bottle and water is gonna spill out.

So what I mean by that is even if we keep the task, you know, the counting backward by seven constant, but depending on how much capacity we have, we can either handle that task easily or that task can turn impossible to us. But the same token, whenever you know we have high capacity if a task is very difficult we put more water in the bottle that task is gonna you know take up a lot of room a lot of our capacity but it same take a token a simple task is gonna just take like a smaller amount of capacity so task demand depends on the difficulty of the task or simple tasks simpler tasks as associated with less demand an easy task imposes little demand and a difficult task imposes more demand task demand can be cognitive you know counting backward by one or by seven perceptual um if i ask you to count um how many you know the number of petals a flower has If it's a small flower, you only have a small amount of petals, but if the petals are smaller and it's a bigger field of flowers, that's going to be more challenging. Or more difficult. If I ask you to push a button every time you hear a bell, versus I ask you to press... 10 different keys on your keyboard in a random order when you hear a bell.

Of course, both tasks require a motor response, but in the former case it's much easier than in the latter. So task demand can be cognitive perceptual motor or a combination of the three. So to sum it up, task performance is dependent on the amount of the capacity plus the demand associated with the task.

Changes in one or both factors will affect the overall load imposed on the person, operator, users. So going back to attention, if say we're driving our car in the morning after a nice sleep, we can easily pay attention to driving and listening to an audio book. But maybe on the way back at night, even listening to an audiobook or having a conversation with the passenger, that's something too much for us to handle in addition to driving.

A task that is commonly used, a paradigm that is commonly used for test selective attention is the spruik task. So some of you may already be familiar with this task. but how it works is they let the words be presented. In this case, you see the word red and the color it is presented is green.

So the task for the participant, whenever they are presented with this word, is to say aloud the color of the ink. so in this case the response would be green in this case the response would be blue because the the color of the ink is blue in this case would be yellow red blue there are certain conditions we call congruent let me see yeah so there are some conditions that are called congruent where the color of ink matches the word so if you see a word you know yellow in yellow that's a congruent condition in this case on the other hand is incongruent in that the word is yellow but the code the ink is blue so this task has used commonly to measure selective attention. So whenever the two information, the color and the word match up, the participants are much faster at responding to producing the correct answer. On the other hand, whenever the condition is incongruent, so the color doesn't match the word, participants are much slower and they're the accuracy goes down. So this type of task is informative because it provides information how we process information you know attentively in our surrounding environment.

These are some alternatives to the Stroop test for instance not that relevant. So In particular, this type of task is important because it tells us about our inhibitory control. In the congruent situation where the color and the word match, we have that automatic response in producing the response and that response is much faster and much more accurate.

On the other hand, whenever we see an incongruent situation we have to inhibit our response for instance just to give you an example if you see in this situation where the color is blue and the word is blue our response will be blue okay so in this in this case you know we're much fast faster but in a different situation where the word is blue but the color is red we have these response of seeing red okay because our attention is really automatically directed to the color of the word not to the word itself. The color of the word is much easier to process than the semantics of the word. Okay, so in this case you see a blue in blue the first information that sort of activates our attention you know that passes that threshold that we talked about prior is the color blue.

On the other hand here the you know because the color reaches that threshold much faster our automatic response would be red okay but red in this case it would be the incorrect answer the correct answer would be blue because that's you know the word so in that case we have to inhibit that the color and try to pay attention to the word itself So that's what executive functions do. Executive function, again, as I said earlier, you can think of it as an attentional manager. Control attention, dealing with conflicting responses. In the case of the Stroop task, there are two sorts of information. One is task relevant, which is the word itself, and one that is not task relevant, which is the color of the word.

So we need to inhibit the sort of attend with the information, the color information, that we automatically pay attention to. So we need to inhibit that response and instead pay more attention to what's task-relevant. So that's something that executive functions do. So they control attentional control, cognitive inhibition, and working memory.

The neuropsychological evidence show that These executive functions are usually located the prefrontal cortex. There's a lot of work studies and case studies being done in executive function especially with clinical populations. Damaged or you know yeah damaged like the frontal cortex has been you know and so ineffective executive functions it's been associated with problems in planning, organizing, prioritizing. Think about again the amount of information that is present in your in the room that you're in even if it's a quiet room but you have the video to pay attention to you may also have your you know somebody in the other room making noises a noise coming from the street etc your phone somebody texting you so there's a lot even in such a quiet environment there's a lot of information that competes for your attention let alone in a much more active environment if you're driving you have to pay attention to the street, to the weather, to the other cars, to if you're driving in a residential area, to pedestrians, to animals. So in that case having our executive functions working properly it's necessary for our survivals and for our safety.

So having executive functions damaged It's really, without exaggerating, like a life and death kind of situation. Lack of attentional flexibility, impaired concept formation. These are consequences of poor executive functions. Inability to monitor and adapt behavior consistent with social circumstances. You may be familiar with Tourette's syndrome and in that case Tourette's syndrome is associated with ineffective functioning of deficit to the executive functions.

So patients with this condition, they tend to utter words that they're not maybe out of place. And this is because they have troubles inhibiting their thoughts. So whatever thoughts come to mind, they sort of, you know, there's no filter.

You know, there's less of a filter. And so they end up adding words that, again, they're out of place. Evidence also showed that adults with autistic spectrum disorder have been shown impairment in certain executive functions, like understanding others'state of mind. I mean, state of mind is the ability to understand the other people's state of mind.

So if you're talking to somebody and that person is showed distress in a normal individual, normal individual should be able to pick up on those clues. But on the other hand, there are certain clinical populations that they lack that. ability.

In this figure here, if you compare just visually the red areas in the control group, subject without autism, and the autistic group, you will see that these are areas that receive activation. They are much smaller in the autistic group than in the normal control group. So this is it for this lecture. Again, in the next lecture we'll continue our discussion of attention and in particular instead of talking about selective attention like we did today, we'll talk about divided attention and sustained attention.

So that's it for today. I will rest your day. Bye.

Transcript for:Understanding Attention in Cognitive Ergonomics

Transcript for:
Understanding Attention in Cognitive Ergonomics