Neurological fatigue is an overwhelming feeling of tiredness which can be debilitating enough to prevent people from doing everyday activities like getting dressed, going to the shops or preparing food. Unlike physical fatigue, neurological fatigue is not alleviated by taking a rest.
It might surface immediately or after some time and can last for months or even years. It can also develop in patients with neurological disorders, such as Parkinson's disease, multiple sclerosis, and dementia. Neural fatigue and physical fatigue, while sometimes present together, are not the same.
Conditions that cause neurological fatigue include:
Traumatic brain injury. Post-polio syndrome. Chronic fatigue syndrome. Functional neurological disorder.
During PEM, any ME/CFS symptoms may get worse or first appear, including difficulty thinking, problems sleeping, sore throat, headaches, feeling dizzy, or severe tiredness. It may take days, weeks, or longer to recover from a crash. Sometimes patients may be house-bound or even completely bed-bound during crashes.
Doctors might refer patients to see a specialist, like a neurologist, rheumatologist, or a sleep specialist, to check for other conditions that can cause similar symptoms. These specialists might find other conditions that could be treated. Patients can have other conditions and still have ME/CFS.
'Normal' fatigue is time-limited and alleviated by rest, whereas 'pathological' fatigue, such as that experienced following brain injury, may be present most of the time. It may not improve with rest and is likely to significantly impact on people being able to do the activities they want to do.
Mental or Cognitive Fatigue (CF) can be defined as a decrease in cognitive resources developing over time on sustained cognitive demands, independently of sleepiness.
Methylphenidate reduces mental fatigue and improves processing speed in persons suffered a traumatic brain injury.
Prolonged mental activity leads to the accumulation of a potentially toxic neurotransmitter in the prefrontal cortex, according to a study published in Current Biology. The researchers suggest the brain slows down its activity to manage the buildup, offering an explanation to why we feel tired.
There are three types of fatigue: transient, cumulative, and circadian: Transient fatigue is acute fatigue brought on by extreme sleep restriction or extended hours awake within 1 or 2 days.
Antidepressants. Low doses of drugs like amitriptyline (Elavil), nortriptyline (Pamelor), trazodone (Desyrel), doxepin (Sinequan), and mirtazapine (Remeron) are used in chronic fatigue syndrome for their calming effects.
In most cases, there's a reason for the fatigue. It might be allergic rhinitis, anemia, depression, fibromyalgia, chronic kidney disease, liver disease, lung disease (COPD), a bacterial or viral infection, or some other health condition.
It's unlikely that you'll need an MRI for a diagnosis of fibromyalgia or chronic fatigue syndrome unless your particular set of symptoms is similar to that of a neurological illness that requires evaluation with an MRI. You may also need an MRI at some point to diagnose an injury or a different illness.
Diagnosing ME/CFS
The GP will ask about your symptoms and medical history. You may also have blood and urine tests. As the symptoms of ME/CFS are similar to those of many common illnesses that usually get better on their own, a diagnosis of ME/CFS may be considered if you do not get better as quickly as expected.
It is possible that CFS is underdiagnosed in more than 80% of the people who have it, or is often misdiagnosed as depression.
There are currently no diagnostic tests for ME/CFS. To test whether they could use ATP consumption to identify individuals with ME/CFS, a team led by Dr. Ron Davis at Stanford University developed a technique called a nanoelectronics assay that can measure the electrical responses of cells in real time.
Scientists measuring sleepiness have found that sleep deprivation leads to lower levels of alertness and concentration. It's more difficult to focus and pay attention, so you're more easily confused. This hampers your ability to perform tasks that require logical reasoning or complex thought.