I understand that this cognitive function deterioration is due to the cyst in the parietal region of the
brain. Consult your neurosurgeon for analysis of both the cysts including the one
in the parietal region and the cerebellum. Depending on the large size and other pressure symptoms like headaches, nausea, blurred vision reflecting increased intracranial pressure, these would require a craniotomy and excision. Hope this helps. Take care.