Existential Overhead - the cost in distraction and stress of uncompleted tasks.A few years back I started shopping around the concept of existential overhead. The concept is fairly straightforward. There simply is no such thing as out of sight, out of mind. When you have a workload, you are always thinking about the individual elements of that workload. In the back of your mind, you know what you haven't done.When your backlog is an amorphous bunch of tasks, all things are psychically equal. Cleaning the cat box and saving for retirement and getting married all have the same weight. The lack of definition is like waiting for news from someone and they don't call, people start to fill in the blanks with their fears.Your brain not only thinks about this undifferentiated backlog, it hates it. It wants it to go away. Hate is heavy and negative.What's the best way around this? Understanding. Microsoft's Bing ads are selling Bing as a filter for "search overload". We have so much information flying at us, search engines need to get better and better at filtering the information so we get what we need. We get the information of value.Kanban is similar, kanban is a visual filter for the work we have taken on. Kanban helps tame our workload and thus make it cognitively manageable. When we have more understanding of the work we need to do, its impact on our time, and where value lies - our existential overhead diminishes. We have less negative or fear-based thoughts of work and replace that with positive and understanding-based thoughts.Kanban is a metacognitive tool. Your tasks themselves are pieces of understanding about actions you need to take. The kanban takes those bits of uncoordinated understanding and puts them in a framework of systemic understanding. To the human brain, this is the best chocolate soufflé in history. Your brain eats this stuff up.A few posts back I talked about how kanban helped your train your brain. This is the training. Kanban's visual nature gives work a logical flow and a set of evolving, flexible and powerful rules under which to operate. As your understanding of your work evolves, your kanban grows with it. As you understand more, you filter better.As you filter better, your overhead diminishes. Overhead is where most waste lies. So if your existential overhead diminishes the time you spend consciously or subconsciously thinking about your undone work dissipates - freeing your brain to think, to do, to learn, or to simply take a break.