Cognitive problems, also referred to as cognitive deficits or dysfunction, occur when a person has difficulties processing information, including mental tasks such as attention, thinking, and memory. Approximately 20% of people who undergo chemotherapy will experience some cognitive problem side effects, including children. The difficulties they face usually vary in severity and make it hard to complete daily activities. People who experience severe cognitive problems are encouraged to speak with their doctor and/or social worker about ways to manage the problems they face.

Symptoms

Relieving side effects, also called symptom management, palliative care [2], or supportive care, is an important part of cancer care and treatment. Talk with your health care team about any symptoms you or the person you are caring for experience, including any new symptoms or a change in symptoms.

Cognitive problems include difficulties in many areas, such as:

• Difficulty concentrating or paying attention (short attention span)
• Memory loss or difficulty remembering things (especially problems with short-term memory)
• Problems with comprehension or understanding
• Difficulties with judgment and reasoning
• Impaired arithmetic, organizational, and language skills (such as not being able to organize thoughts, find the right word, or balance a checkbook)
• Problems performing multiple tasks (multitasking)
• Behavioral and emotional changes, such as irrational behavior, mood swings, inappropriate anger or crying, and socially inappropriate behavior
• Confusion (delirium) [3]

Of special note, “chemo brain [4],” sometimes called “chemo fog,” is the term often used by cancer survivors to describe the cognitive problems experienced by some people after receiving chemotherapy. These people may experience long-term problems with mental skills such as memory, thinking, and concentration. People sometimes say that chemo brain feels like being in a mental fog.

Causes

Cognitive problems are often caused by many factors, including cancer, cancer treatments, medications, or other disorders:

• Chemotherapy [5], especially high-dose chemotherapy
• Radiation treatment [6] to the head and neck, or total body irradiation
• Brain surgery, in which areas of the brain may be damaged or disrupted during a biopsy or the removal of a cancerous tumor
• Hormone therapy, immunotherapy, and other medications (such as anti-nausea medications, antibiotics, pain medications, immunosuppressants, antidepressants, anti-anxiety medications, heart medications, and medications to treat sleep disorders)
• Infections, especially those of the central nervous system (brain and spinal cord), and infections that cause a high fever
• Brain cancer [7]
• Other cancers that metastasize (spread) to the brain
• Other conditions or symptoms [7] related to cancer or cancer treatments, including anemia, fatigue, stress, depression, insomnia, hypercalcemia (high blood calcium), and electrolyte (a mineral in your body, such as potassium and sodium) imbalances that can lead to dehydration or organ failure
• Not having enough of specific vitamins and minerals, such as iron, vitamin B, or folic acid
• Other brain or nervous system disorders unrelated to cancer

Management

Cognitive problems caused by a reversible condition, such as anemia or an electrolyte imbalance, usually resolve after the condition is treated. Likewise, problems caused by a medication should go away after the medication is stopped. Problems related to cancer in the brain usually improve with treatment, but some symptoms may continue. Unfortunately, cognitive problems related to chemotherapy (such as chemo brain), radiation therapy, or other cancer treatments may continue indefinitely. Management of these long-term cognitive problems may include:

• Medications, including stimulants, cognition-enhancing drugs commonly used to treat Alzheimer's disease, antidepressants, and opiate antagonists (drugs that block the actions of narcotics, such as morphine)
• Occupational therapy and vocational rehabilitation, to help people with the activities of daily living and job-related skills
• Cognitive rehabilitation (also known as neuropsychological rehabilitation) and cognitive training, to help patients improve their cognitive skills and find ways to cope with cognitive problems

Suggestions for coping with cognitive problems

• Use a calendar or daily organizer to keep track of appointments, activities, and important dates.
• Ask people to repeat information and write down new information (names and phone numbers); use a tape recorder or take notes during conversations.
• Post reminders and make lists.
• Exercise your brain by doing brain-strengthening mental activities, such as solving crosswords or puzzles, painting, playing a musical instrument, or learning a new hobby.
• Make time for physical activity [8], as it can increase mental alertness. Try walking, swimming, doing yoga, or gardening.

Cognitive problems in children

Young children (age 5 and younger) are more likely to have long-term cognitive problems, especially those who receive chemotherapy and/or radiation therapy that is directed to the head, neck, or spinal cord; total body radiation; and chemotherapy delivered directly into the spine (intrathecal chemotherapy) or the brain (intraventricular chemotherapy).

Furthermore, these cognitive problems can occur months or years after treatment ends and can continue into adulthood. Some of these issues include:

• Decreased overall intelligence (lower IQ)
• Learning disabilities
• Decreased attention span and attention deficit disorders
• Delayed development, including delayed social, emotional, and behavioral development
• Lower academic achievement (especially in reading, language, and mathematics)
• Decreased receptive language skills (the ability to understand or comprehend language) and expressive language skills (the ability to put thoughts together in a way that makes sense)
• Decreased nonverbal and verbal memory skills

Your child may receive occupational therapy, speech therapy, behavior therapy, social skills training, cognitive rehabilitation, and/or medications (such as methylphenidate for attention deficit disorders) to help treat cognitive problems. Some children may need to learn new ways of learning in school or maintaining attention. Additional in-school options such as specialized reading and mathematics instruction, special education programs, and IEPs (individualized education programs) are also helpful. Because early intervention seems to offer the greatest benefit, it is important for parents to be aware of possible cognitive problems and to talk with their child's pediatrician, oncologist, or other member of the health care team as soon as they suspect a problem.

More Information

Rehabilitation [9]

Late Effects of Childhood Cancer [10]

Types of Treatment [11]

Additional Resources

Oncology Nursing Society: The Cancer Journey: Memory/Mental Impairment [12]

LIVESTRONG: Cognitive Changes [13]

Last Updated: February 21, 2012