There are two different categories of symptoms to focus on. Cognitive and memory symptoms/dysfunctions is one. Pace and persistence is the other. Pace and persistence means you can't maintain a satisfactory pace (speed) doing the work activity and persistence means you can not last an entire continuous work period. Many of us can struggle through on the cognitive/memory issues with work-arounds. The mental fatigue that requires frequent breaks is often a bigger problem. Employers do not want workers who need constant breaks.

The SSDI Blue Book has a list of symptoms. Here is a link to the Mental Disorders section
http://www.ssa.gov/disability/profes...dult.htm#12_02
This includes both mental illness and neurological injury caused disabilities. Don't get freaked out by the term Mental Disorders.
There is also a section on Neurological Disorders at
http://www.ssa.gov/disability/profes...ical-Adult.htm
But, it refers over to Mental Disorders for non-Epilepsy issues.

There is a description of the evidence needed, lab work, psychological testing, doctor's diagnosis, etc.

Just working through the application can give you a good idea of your pace and persistence issues.

I hope this helps.

My best to you.