know several techniques to improve attention and attention span including practice, active thought and the creation of mental models etc.
Attention can be improved by practice. Practice listening to others. Try to select a strategy for different sorts of information. For instance, if someone is talking about holidays, try to create a detailed mental image of the place. Ask questions if necessary. If someone keeps repeating themselves (is boring), try to assess how many new things they say and how long it takes to say them.
The knowledge named 'techniques to improve attention' is considered to be rather important.
In addition, the knowledge is thought to be quite simple and mostly easy to understand, it is generally learned by study, and is partially specialised knowledge.
Opinion is that it is fairly justifiable knowledge.