[lynx23]

The ability to retain information is mostly fueled by your interest towards the topic, and not by your inherent ability to retain in general. This is what neuroscience has figured out. And it confirms very much my own observations during my life time. Inherently uninteresting topics or things I was forced to learn but which never resonated with me were always difficult to impossible to remember. Things I care about, or which interest me greatly, were almost easy to learn. Reading a document about an interesting topic cover to cover is easy. Keep that in mind next time you think you have a hard time learning something.

[TheHumanist]

It isn't as much learning as maintaining focus. I struggle badly with that regardless of my interest in a topic.

[lynx23]

I submit maintaining focus is also easier if the topic is inherently interesting. However, you sound like yu are describing something like ADHD, which probably needs a more specific approach.