Sometimes your brain turns into a mush and your thinking centre shrinks. So you lose clarity of thought you are unable to concentrate and your memory betrays you. This cognitive dysfunction is known as brain fog. It could be a short-lived condition triggered by acute stress or anxiety or a chronic condition resulting from some other medical conditions and drugs. Our brains relies on a lot of factors like nutrients psychological condition lifestyle etc. to function optimally. That is why brain fog is often the outcome of mental fatigue stress lack of sleep hormonal changes a diet with insufficient nutrients