Attention, Thinking, and Memory Problems

Approved by the Cancer.Net Editorial Board, 12/2019

You may have problems thinking, paying attention, and remembering things when you have cancer. The medical term for this is "cognitive problems."

More than 70% of people with cancer have these problems, and about a third of people still have them after treatment. Attention, thinking, and memory problems can be more or less severe. Even mild problems can make daily activities difficult. The information below tells you how to recognize these problems and what to do.

Signs of attention, thinking, and memory problems

Signs of attention, thinking, and memory problems can include the following.

  • Trouble concentrating, focusing, or paying attention.

  • Difficulty remembering things, such as names, dates, or phone numbers.

  • Feeling disoriented, like you are in a "mental fog." You might have difficulty finding your way around.

  • Feeling very confused, taking longer to deal with new information, or having difficulty understanding things.

  • Difficulty making decisions or thinking things through.

  • Difficulty organizing your thoughts or doing mental tasks, such as finding the right word or balancing your checkbook.

  • Problems doing more than one thing at a time.

You might also notice changes in your emotions and behavior. You may act in ways you never did before. You might have mood swings, get angry or cry at unusual times, or act differently in social situations.

How severe these problems are depends on many factors, including:

  • Your age

  • Your general stress level

  • Your type of cancer, where it is, and your treatment

  • If you had depression or anxiety in the past

  • How much help you have access to for mental and emotional problems

Talk with your doctor if you or your loved one develop these symptoms. Managing symptoms is an important part of cancer care and treatment. It is called palliative care or supportive care. Attention, thinking, and memory problems are just as important as other symptoms during treatment. 

Causes of attention, thinking, and memory problems

You may hear the word "chemobrain" to describe difficulty thinking clearly after chemotherapy. But people who do not have chemotherapy also have these problems. In fact, some people have attention, thinking, and memory problems before they have any treatment. The general stress of a cancer diagnosis may play a role.

Besides chemotherapy, causes of these problems can include:

  • Radiation therapy to your head, neck, or entire body.

  • Brain surgery. A biopsy or surgery can damage or disrupt areas of the brain.

  • Brain cancer. This could be a tumor that starts in the brain or cancer that spreads from somewhere else.

  • Other types of medications. These may include:

    • Hormone therapy

    • Immunotherapy

    • Medications to control pain or nausea

    • Antibiotics

    • Medications that make your immune system less active

    • Medications for depression, anxiety, heart problems, or sleep problems

  • Infections, especially in the brain and spinal cord, and infections that cause a high fever.

Other conditions or symptoms related to cancer or treatment can affect your attention, thinking, and memory. They include:

  • Anemia

  • Fatigue

  • Sleep problems

  • Problems with your body's levels of electrolytes, or specific vitamins and minerals, such as iron, calcium, vitamin B, or folic acid

  • Dehydration

  • One or more of your body's organs not working well (organ failure)

  • Stress, anxiety, and depression

  • Social issues, such as:

    • Not being able to work

    • Earning less or losing your regular income

    • Your role in the family changing because of cancer and treatment

Managing attention, thinking, and memory problems

Some problems with attention, thinking, and memory go away when you get treatment for the condition causing them. For example, treating anemia or an electrolyte problem usually makes the problems go away. Medication problems also go away after you stop taking the medication or take a different dose. Problems related to cancer in the brain usually get better with treatment. But you may still have some symptoms.

Unfortunately, problems related to chemotherapy, radiation therapy, or other cancer treatments can last a long time. Treatments may include:

  • Medications

  • Occupational therapy and vocational rehabilitation. These types of therapy help you with daily activities and job skills.

  • Specific rehabilitation and training for attention, thinking, and memory problems.

Ways to cope with attention, thinking, and memory problems

Here are some ways to cope.

At home

  • Keep a checklist of daily reminders. Put it where you can see it often. Keep a copy at work if you need to.

  • Get ready for the next day by setting out the things you will need the night before.

  • Color code or label certain cabinets or drawers where you store things at home.

  • Put things, such as car keys, back in the same place every time. This helps you find them easily.

  • Get rid of clutter, such as extra papers, books, and other items around your home.

  • Store important phone numbers in your cell phone. Or put a list next to your home phone. You can carry an address book in case you forget to bring your cell phone when you go out.

At work

Talk with your employer if you are having problems at work. Discuss ways your employer could help, such as changing your workload or deadlines. Read more about going back to work after cancer.

At the doctor

Don’t be afraid to ask your doctor questions, even if you feel like you are repeating yourself. Use a notebook, voice recorder, the Cancer.Net mobile app, or an ASCO Answers guide to record the answers. You may ask a friend or family member to go to the appointment with you. He or she can help take notes and review them later.

General tips

  • Do one thing at a time. Avoid stopping to do something else.

  • Use word play, such as making up a rhyme, to help you remember things.

  • Get plenty of rest.

  • Exercise. It helps your brain stay alert. Try walking, swimming, or gardening. Yoga or meditation can also help you relax and clear your mind.

  • Do things that exercise your brain. These can include doing puzzles, word games, painting, playing an instrument or learning a new hobby.

  • Carry around a small pad and a pen or pencil to write down notes and reminders. Or download a note-making app on your smartphone and tablet.

  • Use a calendar or daily organizer to keep track of upcoming appointments, activities, and important dates.

  • Place sticky notes around the house and at work to remind you of important tasks. You can also set reminders using your phone or email calendar.

Do not be afraid to ask for help. Talk with your health care team about counseling and other resources and ask family and friends to help when you need it.

Children with attention, thinking, and memory problems

Children age 5 and younger are more likely to have long-term problems with attention, thinking, and memory after cancer treatment. These problems can happen months or years after treatment ends and may continue until the child is an adult.

Some treatments are more likely to cause attention, thinking, and memory problems.  For example, radiation therapy, especially to the head, neck, or spinal cord, and chemotherapy given directly in the spine or brain. 

Unlike adults, children are receiving treatments at the time their brains are developing. After treatment, some children may experience:

  • Problems with learning (learning disabilities)

  • Shorter attention span than normal, or attention deficit disorders

  • Slower social, emotional, and behavioral development

  • Less ability to understand what is said or put thoughts together in a way that makes sense

  • Lower memory skills

There are many treatments for children with attention, thinking, and memory problems. These include occupational therapy, speech therapy, behavior therapy, social skills training, cognitive rehabilitation, and medication for attention deficit disorders. Your child may need to use different ways to learn and pay attention.

Other options include specific lessons in reading and math or special education programs. Starting early seems to help the most. So it is important to know the signs of attention, thinking, and memory problems. Talk with your child's health care team as soon as you suspect a problem.

Related Resources

Mental Confusion or Delirium

ASCO Answers Fact Sheet: Chemobrain (PDF)

Long-Term Side Effects of Cancer Treatment

Late Effects of Childhood Cancer

More Information

LIVESTRONG: Cognitive Changes After Cancer Treatment

ASCO answers; ChemobrainDownload ASCO's free Chemobrain fact sheet. This 1-page printable PDF gives an introduction to chemobrain, including causes, symptoms, treatment, words to know, and questions to ask the health care team. Order printed copies of this fact sheet from the ASCO Store.