Fibro Fog

From March 2011 Fibromyalgia Network enews alert- for educational purposes only

There are many symptoms of fibromyalgia, some that are easier to describe than others. One in particular is, what patients often refer to as “fibro fog.” You may be aware of this symptom but wondered if it was just you or a matter of getting older. Fibro fog is not easy to define, but perhaps you can relate to the situations below.

You frequently get lost in conversations, embarrassed that you don’t recall what you intended to say or what you were talking about in the first place. When someone gives you directions, you know you are in trouble. The instructions vanish from your memory banks a moment after you hear them, and you have to ask for them again and again. And whenever you have something important to say, you are quickly confronted with an inability to find the right words to express yourself. 

Others might tell you that these are everyday occurrences, but deep down, you probably know different. Summing up fibro fog, researcher David A. Williams, Ph.D., of the University of Michigan, says it is “generally experiencing life as through a haze.”¹ Whatever the cause, this symptom is very real.

Fibro fog is baffling and it’s natural to want to know more about it. Could this symptom be related to your pain? It just seems as though there is not enough capacity or space in your brain to manage the pain and process your thoughts. Perhaps your brain is on overload, such that it cannot multi-task (pain and thinking), so your cognitive skills get short-changed. Then again, you are always tired and you don’t sleep well, so possibly these factors play a role in your fibro fog.

Williams and colleagues did a study that attempted to better define fibro fog and look for any symptoms that it might be tied to. By better defining your brain fog, one has to evaluate the different components of cognition, such as your language skills for expressing yourself, your ability to visually perceive distance and location, or how well you can stay focused. To assess these different components, Williams’ study used a validated questionnaire involving 72 fibromyalgia patients and 24 healthy controls (used for comparison).

Identifying which aspects of the cognitive processes are hardest hit by fibromyalgia is essential for being able to study it, but knowing how it relates to the other symptoms would also be very useful. If there is one symptom that it is most often associated with, then better treatment of that symptom might possibly lead to improvements in the fibro fog. 

“The greatest perceived deficit in fibromyalgia was associated with verbal memory followed by attention/concentration and perceived language deficits,” writes Williams. 

To understand what they mean, example questions for these three cognitive categories, which are taken directly from the Multiple Ability Self-Reported Questionnaire (MASQ) that was used in the study, are provided below.² Next to each category in parentheses are the fibromyalgia symptoms that each cognitive component was associated with.

Verbal Memory (sleepiness)
I forget to mention important issues during conversations.
I forget important events that occurred over the past month.

Attention/Concentration (fatigue)
I am easily distracted from my work by things going on around me.
I find it difficult to keep my train of thought going during a short interruption.

Language (pain, fatigue)
I find myself searching for the right word to express my thoughts.
I find myself calling a familiar object by the wrong name.

The fibro symptom of fatigue was the strongest predictor of cognitive difficulties. “Pain was uniquely associated with perceived language deficits, and sleep was uniquely associated with aspects of dyscognition involving memory,” writes Williams. “Somewhat unexpected, pain was not related to attention or concentration.” Thus, this study failed to show that the pain of fibromyalgia is monopolizing the brain’s cognitive resources and impinging upon its capacity to process thoughts. 

No one symptom stood out as being strongly tied to fibro fog. Instead, this study showed that the cognitive disruptions in fibro are “multi-faceted.” Different symptoms were associated with different categories of cognitive impairments. Williams calls for more research to be done on this very real, yet complex symptom of fibromyalgia that can be so life disrupting.

1. Williams DA, et al. J Muscuskeletal Pain 19(2):66-75, 2011.
2. Seidenberg M, et al. J Clin Exp Neuropsychology 16(1):93-104,1994.