“If working memory is impaired, we can’t stay on task or work toward a long-term goal because we can’t keep an idea in mind long enough to operate on it or to ponder, process, sequence, plan, rehearse and evaluate consequences […] A failure of working memory is also why people with ADHD are terrible at keeping track of time [… they] literally forget to worry about the passing time, so they never get started on the tasks at hand.”

John J. Ratey, M.D.
Spark: The Revolutionary
New Science of Exercise and the Brain, p. 150-151.