Cognitive Changes

Cognitive Changes

Cancer and cancer treatment can affect your thinking, memory, concentration, and behavior. These are very real changes, and not imagined. Not everyone will experience cognitive changes. For those who do, changes can be mild or more severe, and often improve with time or treatment.

Cognitive changes can happen suddenly, or they may be noticed slowly over time. Some of these changes may be temporary. They may be the result of surgery, tumor removal, increased stress, or treatments like chemotherapy. These are common changes and may improve over time. In other people, these changes in memory or thinking are more persistent. They may begin to affect their ability to do daily activities such as work or self-care. It can be very upsetting to realize that your cancer has been successfully treated, but you still do not feel like your old self.

Pay attention to any changes you notice. Ask your family or friends to watch for changes as well. If you notice changes in your thinking, memory, or behavior, keep a record of the problems that you have and ask your family or friends to watch for additional problems. Make an appointment to talk to your healthcare team about these symptoms as soon as possible. Some changes are caused by an underlying condition, which may be treatable. Treating the underlying condition often reduces or removes cognitive problems. 

Whether cognitive changes will improve or be permanent depends on their cause.

  • Acute cognitive changes (delirium) that occur because of certain medicines often improve when you stop taking the medicine.
  • Chronic changes (dementia) are often not reversible, but may be improved if the cause of the problems can be corrected. 


Acute/Sudden Mental Changes

Sudden changes can be signs of a more serious medical issue, including infection or a reaction to medication. Symptoms may include: 

  • Changing level of alertness/consciousness 
  • Not knowing what is going on around you
  • Agitation or confusion 
  • Loud, aggressive behavior 
  • Hallucinations (seeing or hearing things that aren’t there) 

If you notice these changes, contact your healthcare team right away to discuss next steps, or go to the emergency department. 

These changes might be a sign of a condition called delirium. Delirium refers to the state of being very confused. It can come and go throughout the day. Some people with delirium act tired or withdrawn, while others seem agitated or hyper. Delirium is a side effect of certain medicines and generally improves when you stop taking the medicine.


Gradual Onset Changes/Dementia 

These are changes in memory or thinking due to the cancer/treatment, not Alzheimer’s. They can occur slowly and can be long-lasting. They may not even appear until after treatment. Symptoms include: 

  • Problems with memory 
  • Poor judgement/making unsafe decisions 
  • Changes in personality 
  • Disorientation


Chemo Brain

People often use the expression “chemo brain” to describe mild changes in their ability to think, concentrate, or remember during and after cancer treatment. Symptoms may include:

  • Difficulty concentrating 
  • Forgetfulness
  • Confusion 
  • Inability to think clearly or find the right words
  • Difficulty multitasking


Coping With Chemo Brain

These tips can help you cope with mild cognitive changes. Be sure to talk with a healthcare professional in case there is an underlying condition that can be treated.

  • Tell a family member or friend. Let people know what’s going on so they can support you.
  • Plan your day and schedule things that require the most concentration for when you feel best.
  • Stay organized by taking notes, recording things, using a calendar for important dates and a pillbox for your medication. 
  • ​Make time for physical activity as it can increase mental alertness. 
  • Try to focus on one thing at a time. Whenever possible, avoid having conversations or working in an environment with distractions.
  • Develop routines to stay on top of things.
  • Get enough rest.
  • Eat a healthy diet.
  • Keep moving. Even a few minutes of exercise can be helpful.
  • There are programs for cognitive changes that might help with your memory or other issues. Ask your oncology team for possible referral.


Discover More About Managing Treatment Side Effects