What is “chemo brain” or brain fog from cancer?

Cancer’s impact on cognitive health

Posted 11/20/23 - 5 min. read.

Some individuals with cancer experience cognitive issues before, during and after treatment. Survivors describe difficulties with memory, focus and word-finding. This is often referred to as “chemo brain” or “brain fog.”

This change in thinking ability, or cognitive function, was first described by survivors after they received certain types of chemotherapy, hence the nickname chemo brain. 

Experiencing memory problems, difficulties with multitasking, reduced attention and decreased concentration/focus following cancer treatment can be common — as much as 75% of those impacted by cancer may experience some form of chemo brain. 

Fortunately, these symptoms usually do not last for a long time. 

Cause of brain fog during cancer

The cause is still not entirely certain. But, researchers are actively looking for answers. 

While chemotherapy often leads to this side effect, chemo brain is not actually the most appropriate name. Not every patient who has chemotherapy gets chemo brain and not every patient who gets chemo brain has chemotherapy.

This side effect has also been linked to other forms of cancer treatment like hormone therapy and radiation therapy. 

Experiencing any form of cognitive decline following cancer treatment can also be linked to the stress the brain endures during treatment.

What brain fog feels like

Patients often describe chemo brain as a fog that makes it difficult to think clearly, problem solve or multitask. Even on good days, recalling a word or accomplishing a few tasks at once (texting while talking, talking while following a recipe/directions) seems harder.

Attending to a task can become more difficult and cause more fatigue. Focusing during an important work meeting or writing a report may feel harder and you might feel more tired after. 

Your ability to remember things while doing an activity (working memory) may also suffer.

For example, your ability to remember if you locked the door when leaving the house while talking on the phone becomes harder. Or, you may experience difficulty remembering details of a meeting or directions when given to you with multiple stages (e.g., take a left at the red house, then go about a mile down and take another left).

The difference between this type of brain fog and cognitive issues associated with aging, is that it is related to cancer treatment (right before, during or after) and is unlike what you felt or how you performed before. Most importantly, you feel a difference.

In typical age-related decline, it comes on gradually over time. 

Symptoms of brain fog

In addition to an overall fogginess of the mind, there are commonly reported symptoms of brain fog:

• Word-finding difficulties, like searching for a word that's on the tip of the tongue
• Taking longer to finish routine tasks
• Trouble with verbal memory, such as remembering key parts of a conversation
• Trouble with visual memory, such as recalling an image or list of words
• More difficult/slower to learn new skills
• More difficult to do things that were once automatic or simple for you, such as everyday math
• Decreased mental health

It can be frustrating to feel as though you can’t focus following cancer treatment, especially if your body is recovering more smoothly.

But it’s important to remember that this may not be permanent, and there are ways to help manage and overcome it.

Coping with brain fog from cancer

If you are frustrated with your post-cancer cognitive issues, you are not alone. Many survivors describe cognitive changes after cancer as frustrating.

The most important next step is to talk to your oncology providers about what you are experiencing.

Partnering with a care team that specializes in cancer rehabilitation and cognitive rehabilitation can help you adapt and regain your thinking skills.

Here are some ideas that could potentially help make your daily life a bit easier:

• Try a daily planner, pocket calendar or your smartphone’s notes app to keep important details in one place.
• Build your brain “muscles” by trying a new activity, learning a new hobby, reading a new type of book or listening to a new idea.
• Sleep is healing. Create a sleep routine by going to bed and waking up at the same time every night.
• Decrease distractions when trying to focus (turn your phone on Do Not Disturb while trying to get that report done). 
• Movement is medicine. Exercise has been shown to improve the way we feel and our thinking skills.

We can help

ReVital Cancer Rehabilitations' occupational therapists and speech-language pathologists are specially trained to identify and prescribe effective treatment plans for all forms of cognitive decline relating to cancer treatment.  

No matter where you are on your cancer journey, a comprehensive rehabilitation program can help.

Learn more about ReVital Cancer Rehabilitation and how our therapists can help you do what matters most.