Brain fog due to fibromyalgia (FMS), a.k.a. fibro fog, is a commonly reported symptom of fibromyalgia. Fibromyalgia patients often describe multiple sensations of fatigue and listlessness combined with transitory states of confusion, poor attention and concentration, and short-term memory loss. This fibro fog tends to exacerbate the deficits in daily functioning that a fibromyalgia sufferer must deal with.
What causes fibro fog? There's no conclusive origin for this symptom of FMS, nor an explanation as to why it exists in varying degrees for different fibromyalgia patients. Sleep deprivation and significant difficulty in achieving and/or maintaining deep level sleep, however, may very well point to the answer. It is at the deeper levels of sleep (delta wave sleep) that a person's mind conducts its internal "housekeeping." During this phase of sleep, newly acquired information is assimilated and integrated. The inability to get enough restorative deep-level sleep may have an impairing effect on an individual's ability to recall information or operate at a normal level of mental efficiency.
If the SSA agrees with your diagnosis of fibromyalgia and believes it is a severe impairment, the SSA will assess your physical and mental abilities and come up with an RFC. (This is discussed in our general article on fibromyalgia disability.)
If you have fibro fog that affects your ability to concentrate or remember instructions because of mental confusion and short-term memory loss, the SSA will give you a mental RFC. Your mental RFC will rate your ability to do skilled work, semi-skilled work, or unskilled work. If your RFC says you can do unskilled work, the SSA will likely say that you can get a job. But if you have a mental RFC for unskilled work (because of poor concentration and inability to follow instructions), and a physical RFC that allows you to do only desk jobs, the number of jobs you can do will be greatly lowered. For more information, see our section on getting disability with an RFC.