Neurotoxicity please help me understand?

So is there any actual symptoms that seperate this from withdrawal? I’m 26 months in and doing pretty badly and just seeing this has cause panic and disarray. Can someone please explain this to me and how I know what level of destruction my brain is at??? Worried worried worried…

if your bedridde  and cannot function..you are worse off thancmost. but there is always chance for healing of some sort just dont know how abd when