Here is the full transcript of award-winning researcher and educator Dr. Sasha Vassar’s talk titled “The Learning Blind Spot: Why We Miss What Matters” at TEDxUNSW Salon 2025 conference.
Listen to the audio version here:
DR. SASHA VASSAR: What if I told you that one of the biggest challenges in learning isn’t a lack of intelligence or effort, but is a blind spot? Every day students sit in lectures, they highlight extensively, take extensive notes, believing that they’re mastering the content. I mean, I was one of those students back in the old days. I used to love sitting in lectures, taking very detailed notes. It really made me feel like I was achieving something, like I was learning.
But here’s the kicker. Many of these strategies simply do not work. And now with ChatGPT at their fingertips, students can get very, very quick answers instead of engaging in the struggle that is required for deeper learning. Research tells us that students often rely on these ineffective learning strategies not because they’re lazy, but because they just don’t know any better.
When I was a little kid, my mom used to send me to bed before a big exam with a textbook to sleep with under my pillow, which clearly was a fantastic resource for learning. And to be fair, it was not very comfortable for sleeping, nor I think it helped me with any of my exam performance, but it was yet another ineffective learning strategy and probably one that I should have known better would not work.
Finding Bugs in Code and Learning
Before I became an academic, I worked in industry as a testing engineer. My job was to find bugs in code, to replicate them, and just break things, basically. Yet some bugs always stayed hidden to me, invisible no matter how hard I looked.
I remember one particular time, hours of debugging, trying everything. I thought I was losing my mind, or that I’d already lost it. Double-checked everything, rewrote bits of the code, and still nothing. Sounded like a case of a missing semicolon for those of you that have done programming, but luckily for my pride, it was a more complex bug.
And just like I couldn’t see this bug that was staring me in the face, students often can be blind to the flaws in their learning strategies. They believe that they’re doing everything right, and yet they don’t see that some of these methods do not lead to the deeper learning.
In my case, my colleague glanced at my screen and was able to find the bug in what felt like seconds. So not good for my pride, but I moved on. And just like that, students face the same issues. Just like I couldn’t see this bug, students face the same issue in their learning. Why did I miss this bug, and why do they miss these key learning moments?
Inattentional Blindness
This happens more often than we think, and I want to actually test this out with you guys. So let’s put it to a little test.
Amazing, so I heard some of you laughing, so you clearly noticed what I thought you would miss. Now, who here counted the number of passes? Was it 20? I can’t actually see you, so I’m just going to keep going. Was it 16? It was 16. And who saw the gorilla in the middle of the screen? Yay, a few of you did.
For those of you that knew to expect the gorilla, though, did you notice that the curtains changed color halfway through? What about one of the players in a black T-shirt left the screen randomly as well? Oh, well, this audience clearly does not have any inattentional blindness.
So what you’ve just witnessed is a phenomenon called inattentional blindness, and much of the research around it is based on a study by Simons and Chabris in 1999. And just like, maybe not all of you, because clearly you are feeling great and you can see the gorilla, just like all of you, some of you, did not miss the gorilla, students often miss the gorilla right in front of them when they’re studying and when they’re learning.
Have you ever kind of experienced this kind of inattentional blindness in class? I bet you have. I bet you’ve gone into a lecture, you’ve taken some really great notes, then walked out of that lecture and could not actually tell what that lecture was about. It does happen, and I always think that when we take these extensive notes, we often miss what the person is actually saying. And when students code along with me in the lecture, they will often miss what I’m saying about the actual code or about the syntax or the structure of it.
Cognitive Load Theory
Now, all of this is based on a learning theory, one of the many learning theories, and this theory is called the cognitive load theory. And this cognitive load theory states that we have a very limited working memory. We can only hold about five to seven elements in our working memory at any one time. That means that we struggle to work with more than five or seven elements at a time. And when students are overwhelmed in their working memory, they just can’t process all the information that’s coming in.
The more cognitive effort a task requires, the more likely you are to overlook something significant because you’re feeling completely overwhelmed. So the harder the material is, the easier it is to overload a person learning.
Now imagine that you are carrying some groceries. One bag, two bag, three bags, three, four, five, still very manageable. You’ve got two hands, you’re able to carry them. What if we keep adding six, seven, eight, nine, 10, 11, 12, 13? Something is going to drop, and that is cognitive overload.
If you’ve done programming, you’ve probably looked at a wall of code and felt completely overwhelmed by it. And that’s because there is way more information on that screen than your working memory can handle all at once.
And one of the hardest things about debugging code is dealing with that sheer volume, lines and lines of logic all demanding your attention at the same time.
And this is not just a coding problem. This happens with essays, with research papers, really with any dense blocks of information.
Strategies to Combat Cognitive Overload
So what can you do to combat this overwhelm? Look at the code and then look away. Give your brain a moment to process. And then when you look back, don’t try and take it all at once. Chunk it. Break it down into smaller, manageable sections.
In code, we use style to style our code. We use indentation, white space, brackets to group logical things together. And this helps us to be able to read the code and not be overwhelmed by the sheer volume. Similarly, in essays, we use paragraphs. We use commas and other punctuation marks to the same effect.
Instead of seeing a huge, intimidating mess, you get left with much smaller chunks that you can actually process. Chunks that you can start to identify patterns, recognize familiar structures and isolate the parts that don’t yet make sense.
Once you’ve chunked your wall of code, you can focus on those smaller chunks. Research them, understand them. And then piece by piece, the code starts to come back together and finally make sense. It’s about giving your brain the space to process, reflect and build understanding. Step by step and chunk by chunk.
Some researchers believe that when we miss something obvious like the invisible gorilla, it’s not because we didn’t see it, we did, but because our working memory was too full to hold onto it. It’s like our brains noticed it, decided, nah, not important and just erased it.
I remember like others watching Game of Thrones, enthralled by it, still waiting for the books to finish. And then who remembers the Starbucks coffee that made its way into the scene? When I was watching this episode, I didn’t even notice it. I was so focused on understanding the dialogue that my brain simply did not compute that there was something else and just, it was not relevant to my understanding. All my cognitive resources were used to understand the dialogue.
And this also applies to techniques like extensive note taking during class. Often when we’re taking notes, we’re so focused on that one task that we become blind to the other information, for example, stuff that is spoken or shown.
In order to prevent the overwhelming feeling and the subsequent blind spots, students can also try and reduce the noise that they can control. Some students face information overwhelm all the time, notifications, social media, multiple screens and multitasking. They all compete for your attention at the same time. And to add to it, educators may unintentionally contribute to your load through very cluttered slides, complex explanations or too many simultaneous tasks. You would feel so overwhelmed looking at something like this that you would struggle to focus on what matters.
Research shows that when cognitive load is too high, students retain less information, struggle with problem solving, fail and fail to see key patterns. So if you’re in the lecture watching a cute video on your phone, you’re listening to the lecturer, you’re also looking up the slides and maybe checking someone out in the audience, you’re probably setting yourself up to miss many important points.
So what can we do to fix this? Strip away those kinds of distractions. Put your phone on focus mode and put it away. Put your laptop on focus mode so you can stop the notifications coming through. Stop taking extensive notes in class. Simply note down keywords that you can then go back to and expand later on. Don’t try and do many things at once, just one chunk at a time, bit by bit.
And whilst the consequences of inattentional blindness and learning don’t seem dire, they are still consequences. A lack of understanding of code down the line may lead to you writing programs that have pretty serious security vulnerabilities or just unexpected failures. And in the moment, it could be a lack of understanding of a topic or failing the course.
Learning from Failure
And whilst in that moment failing feels awful, it’s not the end of the road. Sometimes repeating a course is just what you need to move past those blind spots and to actually get that deeper understanding. Our mistakes allow us to learn a great deal about what we actually don’t know. And even in code, some of the best way to learn is to see code fail and to see it fail for different reasons. It teaches us a lot more than having code that compiles the very first time.
Similarly, when I was doing a PhD, I had three failed experiments in a row and I felt like I had wasted a year of my life by that point and I felt pretty demotivated. And it is really hard to move past that kind of mindset to this particular blind spot.
I still remember what my supervisor said to me that day and I reckon it has changed the way that I view failure forever. She told me that we can’t have perfect experiments that work out all the time, otherwise all we’re doing is just proving what we already know. And if that were the case, we would never make any changes, never have progress and never learn anything new.
Failure is a chance to change the way that we did something, to fill in the gaps, to address our blind spots and to do something again and to do it better.
The Power of Practice
And this isn’t just about programming, it’s about how we approach learning in general. One of the most important things you can do is practice, practice, practice. Build up your vocabulary of problems, approaches and different solutions. Practice helps us to build our expertise which can also combat inattentional blindness. The more I saw different types of bugs, the more readily I was able to fix them the next time that I saw them and the time after that.
And when I, for the life of me, just could not find a bug and completely missed the invisible gorilla in front of me, what is most helpful and what often feels the most counterintuitive is to take a step back and to walk away from the problem. That helps our brain to regulate the load again, because when you come back to this problem a short time later or even the next day, you often perform a lot better than when you did that, when you started.
And that’s because when you walk away from the problem, the active information in your working memory begins to fade and you are no longer trapped in that initial approach that you took. So your brain starts to make different connections and those connections allow you to solve and see a problem in a very different way.
Conclusion
When we manage our cognitive load, we finally see what was invisible all along. The gorilla is standing right in front of us, waiting to be recognized.
At the start, I told you about a bug that I just couldn’t see. And just like the invisible bug, in learning we all have blind spots, moments where we think we are engaging in good learning practices that lead us to understanding, but in actual fact, those practices might be overloading us.
The key isn’t to continue doing the same thing expecting a different result, but to step back, to remove the distractions, to change your perspective and adjust your approach. Because what you’re searching for might be standing right in front of you.
