Question: what nervous system disorder occurs when lesions form on the cerebral cortex causing dementia
[{'answer': 'Arachnoid cysts', 'provenance': [{'wikipedia_id': '17681122', 'title': 'Central nervous system disease', 'start_paragraph_id': 29, 'start_character': 11, 'end_paragraph_id': 29, 'end_character': 26, 'bleu_score': 1.0, 'section': 'Section::::Diagnosis.:Types of CNS disorders.:Addiction.\n'}]}, {'provenance': [{'wikipedia_id': '17681122', 'title': 'Central nervous system disease', 'start_paragraph_id': 30, 'start_character': 0, 'end_paragraph_id': 30, 'end_character': 552, 'bleu_score': 0.976043556018343, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15434535741862710742}, 'section': 'Section::::Diagnosis.:Types of CNS disorders.:Arachnoid cysts.\n'}]}]