It may be one of the most uncomfortable questions one can ask themselves, but after having been a math student for 6 years (currently I'm in my first year as a PhD student), this question seems to become more and more important for me.
Namely, ever since I started studying mathematics at a university, I had trouble following the lecture. It was just too much new and complex information thrown at me at once. I simply couldn't follow the lecturer, as I forgot what they said the moment they started a new sentence. That's why I am talking about working memory and possibly IQ: I can't hold multiple sentences at once in my head simultaneously, my line of thinking and understanding is very linear, it's step-by-step but if I make the next step I've forgotten about the former step. Often I just sit in the lecture trying to process what's been said 15 minutes ago.
I tried taking notes like a stenographer, writing down the literal words spoken by the lecturer. I tried visualizing what the lecturer was saying as subtitles appearing at the bottom of my visual field. Nothing really helped, and I was just confusing myself even more. Another method I've tried was the "note down what you don't immediately understand" method, but I ended up not even properly knowing what I don't understand because as I said, too much new information at once.
So up to this day, lectures and seminaries are utterly useless for me. The only way to learn new information and understand it is if I have it on text, it seems like I can't grasp new information by just listening. My peers can absolutely understand and learn new information by just listening, that's why they actually enjoy extra lectures or seminaries and conferences.
Now to the funny part: I am able to understand spoken lectures and seminaries if they're about humanities, like philosophy for example. It's not a problem for me to listen to them like a podcast and understand everything perfectly. I don't know why it is like that. I don't know what makes humanities lectures easy to understand and follow for me compared to science lectures.
Anyway, what is the current scientific, psychological consensus on that topic? Why do some people cannot get anything out of a lecture? Is it because of their working memory? Aphantasia? IQ? And what should one do to improve it?
