Historically, fibromyalgia has not been thoroughly understood by the medical profession. Debate still rages as to whether fibromyalgia is an independent disorder or a label applied to a collection of symptoms. A new study, however, appears to show that the brains of people with fibromyalgia are receiving sensory overload although it is unclear whether this overload is the cause or the result of fibromyalgia. 
What are the Symptoms of Fibromyalgia?
Most physicians define fibromyalgia as a disorder in which patients experience pain throughout most or all of their bodies. For a diagnosis of fibromyalgia, the pain may manifest as a constant ache for three months or more, or it may be more acute. However, it must occur both below and above the waist, and it must be present on both sides of the body. [2, 3]
Excessive fatigue is a common complaint among those with fibromyalgia. They may report that they awaken fatigued even if they slept through the night. However, as the pain disturbs their sleep, many patients are unable to sleep for an extended period. Furthermore, physicians have found that many patients with fibromyalgia also have a sleep disorder; sleep apnea and restless leg syndrome are the most common sleep disorders noted. 
Cognitive problems are also common among fibromyalgia patients. Many report that they have difficulty concentrating and are easily distracted when attempting to focus on a task. Some patients describe the symptom as a “brain fog” that interferes with their ability to think clearly. 
How the Brain Normally Processes Stimuli
Every day, the brain is subjected to a barrage of stimuli from the environment. Sights, sounds and smells abound at home, in the workplace or virtually anywhere else that people may go. The brain must evaluate every input to determine whether it is important. Unimportant stimuli are then disregarded, allowing the brain to focus only on things that may represent a threat, provide useful input or fulfill a need. This is why many people can complete math problems while the television screen flickers across the room, drive while listening to music or fall asleep despite the noise from passing traffic. 
What is Sensory Overload?
Sensory overload occurs when one or more senses is so overwhelmed by stimuli that it is impossible for the brain to process all input.  Most people have experienced sensory overload at least once. For some, a loud rock concert featuring an extensive light show may be enough to overwhelm their brains. For others, it may be a kindergarten class in which every student is clamoring for attention simultaneously. It is important to note that individuals have varying tolerances for input, so what is overwhelming to one person may not faze another.
What Studies Show Regarding Fibromyalgia and Brain Function
In one recent study, researchers wanted to determine whether the brains of fibromyalgia patients were filtering out unimportant stimuli or continuing to process every input. To test, the researchers fitted fibromyalgia patients and a control group with magnetic helmets. Each subject wore headphones over their ears. All subjects were asked to watch an innocuous slide show. During the slides, researchers secretly introduced small, random sounds and measured the signals each sound evoked in the subjects’ brains. They found that the control group’s brains paid little attention to the sounds; signals from their brains quickly returned to normal. Among fibromyalgia patients, however, the brain signals remained strong for an extended period, indicating that they were still attempting to process the stimuli. 
In a study conducted in 2015, researchers found that fibromyalgia patients suffered from both pain inhibition and cognitive inhibition. Pain inhibition is the brain’s ability to ignore pain, and it has long been accepted that pain inhibition is present with fibromyalgia. Cognitive inhibition, however, has only recently been studied in connection with fibromyalgia. Cognitive inhibition is the brain’s ability to ignore innocuous stimuli, such as background noise, odors or hot or warm room temperatures. 
Another team researched the link between cognitive ability and an excessively sensitized central nervous system, which is known to be common in patients with fibromyalgia. Researchers found that sensitization was linked to cognitive impairment and that cognitive performance was linked to heightened pain sensitivity. 
Different studies have also provided evidence of brain overload in fibromyalgia patients. Fibromyalgia patients had more trouble thinking of words than people with other memory deficiencies. They also had greater difficulty remembering what they heard. 
How Fibromyalgia Overloads the Brain
Despite extensive studies, researchers do not understand the precise mechanism behind brain overload in fibromyalgia patients. More research will be needed to arrive at a definitive answer, but various theories have been proposed. 
One theory proposes that chronic pain can itself lead to a brain that is easily distracted and overwhelmed. Similar findings have been reported in studies involving migraine sufferers, so it is possible that this assumption is valid. However, most experts believe that this explanation does not adequately address the question. 
Many researchers believe that the problem lies in the thalamus. The thalamus is a portion of the brain that receives and processes input from all senses except smell. When the thalamus receives a sensory signal, it determines which portion of the brain needs to handle the signal and relays it accordingly. For example, the thalamus relays visual signals to the occipital lobe, and it relays auditory signals to the midbrain. Specifically, the signals are sent to the primary visual cortex and the primary auditory cortex. 
In essence, the thalamus is the sensory gatekeeper. It decides whether stimuli are important or innocuous, and it does not relay innocuous stimuli to the brain’s upper regions. Researchers are divided, however, on whether the thalamus or the upper brain is causing the fog. In other words, the question is whether the thalamus “freezes up” when it cannot decide which portion of the brain should receive the input or whether the higher regions are slowed by the need to interpret information and filter out the unnecessary stimuli. 
Researchers believe that fibromyalgia is not a disorder that generates pain. Instead, the problem appears to lie in the complex pathways in the brain that control sensory inhibition and the central nervous system. Simply stated, the brain does not know when to “turn itself off,” so it is always on and always ready to react to stimuli. Some researchers believe that depressed levels of serotonin and other neurotransmitters may play a part in an over-stimulated brain, but the evidence is inconclusive. 
Coping with Brain Overload and Fibromyalgia
Every day, researchers are discovering new information about how the brain functions. Studies involving patients with degenerative conditions may help solve the riddle of brain overload as it relates to fibromyalgia. In the meantime, however, physicians are struggling to find ways to treat fibromyalgia. 
Most of the medications prescribed for fibromyalgia are intended to facilitate better sleep, alleviate pain or manage stress. Some physicians prescribe stimulants to help cope with cognitive problems. However, many patients liken the use of stimulants to borrowing energy that cannot be repaid. 
Research has shown that cognitive training programs can be beneficial for patients with many other conditions that affect mental abilities. These programs often consist of in-house sessions combined with software to use at home. Virtual reality games appear to help patients with certain cognitive problems improve their critical-thinking and memory skills, but they have not been studied with fibromyalgia patients as subjects. Therefore, physicians are divided on the issue; some physicians recommend these games for their fibromyalgia patients, but others do not. 
Most experts recommend that fibromyalgia patients make certain changes in their lifestyle. They recommend getting adequate sleep, taking rest breaks whenever needed and eating a balanced diet. Fibromyalgia patients should focus on one task at a time; for example, they should avoid talking on the phone while cooking or watching television while paying bills. Maintaining a routine may be helpful, such as always leaving car keys in the same location or keeping the same work hours. Many patients find that doing something physical can help them clear their fog. Experts also recommend that fibromyalgia patients avoid stress as much as possible. 
Other recommendations depend on the stimuli that bring on the individual’s brain overload. One person, for example, might find a cluttered environment overwhelming, so organization might help. Other people might find their forgetfulness to be overwhelming, and using lists or other types of reminders could help them. People who become overwhelmed by noise may need to avoid loud places, especially if the noise is coming from multiple directions. 
There is no universal method that allows all fibromyalgia patients to find relief from brain overload. Relief may require a combination of medications, cognitive training and lifestyle adjustments. All fibromyalgia patients should discuss their specific symptoms and triggers with their physicians. With studies continuing, however, new information could be uncovered soon that will allow fibromyalgia patients to avoid or treat brain overload.