My father recovered from Covid but now has been showing altered behaviour. He talks excessively and advises people too much. He gets irritated and upset if you interrupt his talking. He has become adamant and irrational. He used to be a very rational person, it doesn't feel like it's him talking. Also he has slurred speech and shaky hands. Are these sort of issues post Covid and do they resolve by themselves? What kind of MRI should be done to assess any damage to the brain?