A neurologist is a medical doctor/consultant who specialises in neurological conditions and can diagnose problems and treat them with medication and give advise on conditions relating to the human nervous system. I haven't seen one of these.

A neuropsychologist is a specialist psychologist who is trained in the area of neurological conditions, but many concentrate on the area of brain injury. They can provide a battery of tests called a neuropsychological assessment that can indicate levels of cognitive impairment and advise on how to manage these. They can provide support around behaviour/fatigue management and provide counselling around the emotional impact of the condition. I have been supported by a neuropsychologist with advice on managing my PCS and return to work, I didn't require a neurological assessment.