Chemo brain is a common term used by cancer survivors to describe thinking and memory problems that can occur after cancer treatment. Chemo brain can also be called chemo fog, chemotherapy-related cognitive impairment or cognitive dysfunction.

Though chemo brain is a widely used term, it's misleading. It's unlikely that chemotherapy is the sole cause of concentration and memory problems in cancer survivors. Researchers are working to understand the memory changes that people with cancer experience.

Despite the many questions, it's clear that the memory problems commonly called chemo brain can be a frustrating and debilitating side effect of cancer and its treatment. More study is needed to understand this condition.