Multiple sclerosis (MS) can not only cause a wide variety of physical symptoms, but also affect the way people think and feel emotionally. It's important to understand what these changes are, and how they may affect you because early recognition and treatment are key to managing symptoms successfully.

The following types of cognitive problems are the most common in MS.

Memory

Until fairly recently, experts believed that the primary memory problem for people with MS was with the retrieval of information that had been stored in memory. In other words, these experts believed that a person could learn new information and tuck it away in memory, but then be unable to recall or retrieve it from storage when needed.

More recent evidence suggests that the problem may involve the initial learning phase. People with MS may need longer time or a few more repetitions to learn and store new information successfully. After it has been stored, however, it can generally be recalled without difficulty. For example, if you have memory problems, it may take you longer than someone without memory problems to memorize a list of words. But once you have the words memorized, you'll remember them just as well as the other person does.

Information processing

Slowed processing is important because it may be the primary reason why a person with MS needs more time or repetitions to learn new information. When processing is impaired, the person has trouble keeping up with incoming information, whether it's from conversations, TV shows, or books. People describe this slowing by saying, "I can still do everything I used to be able to do, but it all seems much slower — like my brain needs to be oiled."

Attention and concentration

Attention and concentration, which form the basis for many other cognitive functions, can also be impaired by MS. For example, people who are used to being able to focus on many complex and competing tasks at the same time may notice some frustrating changes, such as being easily distracted by interruptions or competing stimuli, having difficulty moving smoothly from one task to another, or finding it more difficult to multi-task (an essential skill in any occupation, particularly parenthood).

Executive functions

Executive functions include the high-level processes of planning, prioritizing, and problem-solving. Research has shown that people with MS may find thinking through complex problems or projects more difficult because they lose the mental agility to shift from concept to concept along the way. People often describe this impairment as "feeling stuck" or "lost in a maze."

Visual perceptual skills

Visual perceptual skills, which include simple perception or recognition of objects, as well as sense of direction and orientation in space, can be affected in MS. These problems can interfere with activities ranging from reading a map or driving, to programming your VCR or dealing with those pesky "some assembly required" projects.

Verbal fluency

Verbal fluency includes the ability to find the word you're looking for quickly and easily. "It's on the tip of my tongue" is a particularly common complaint from those who have MS, as is "I'm talking to someone and all of a sudden I'm stuck without the word I need." People who experience these kinds of problems may feel less confident about their ability to talk smoothly and comfortably with others.

General intelligence

People with MS sometimes say they feel "dumber." The good news is that general intelligence is usually not affected in MS. However, individual functions that make up general intelligence, such as memory, reasoning, or perceptual skills, can be affected or slowed temporarily during a relapse or more permanently over the course of the disease. So, a person's intelligence quotient (IQ), which is a composite score made up of individual subtest scores on all these functions, can become lower over time.