Chemo brain is often described as feelings of not remembering things, feeling vague or having trouble concentrating. Doctors may call it mild cognitive impairment. Cognition is used in different ways, but generally means ‘thinking’. Reported side-effects from chemotherapy vary between each person, however patients who have undergone chemotherapy treatment often tell their treating specialists they are having problems with their memory and complain of a ‘foggy head’. Others report no effect on brain function. Research has not been able to determine causes of chemo brain. While studies have shown that some people have problems with memory and concentration after receiving chemotherapy, other studies have found some cancer patients have cognitive impairment soon after diagnosis, prior to receiving chemotherapy. This suggests it is not just chemotherapy causing memory problems and that ‘cancer brain’ may be a more accurate nickname. Other studies have found that hormonal treatment for cancer can also be associated with memory and concentration problems. For most people, the cognitive problems are subtle, but even so can affect everyday life. Generally, memory and concentration problems improve with time, but for some the problem can remain long term. How long is currently not known. It’s important to tell your treating specialist of any changes you experience. There is a lack of evidence for how best to treat cognitive problems associated with cancer. Brain exercises (e.g. memory games) may assist in minimising the impact on the brain, but studies are required to confirm this. Researchers are recommending larger studies to find out more about the impact of chemotherapy on the brain.