“As with most CFS symptoms, cognitive dysfunction waxes and wanes. One report suggests that IQ falls during a flare of cognitive dysfunction, and our personal experience is that memory, attention, processing speed, and other parameters also decline during a flare or relapse. The good news is that cognition improves as one recovers from CFS, and I am not aware of any permanent cognitive deficits resulting from CFS.
The two “never-ending symptoms of CFS” are fatigue and non-restorative sleep. Those two symptoms seem to resolve last when people recover from CFS.”