8 long-surviving children, treated for medulloblastoma with combination radiotherapy and chemotherapy after surgery were examined in order to assess general intelligence, immediate attention and prolonged attention. Their siblings or first cousins were selected as controls. The children with medulloblastoma performed significantly worse than their peers, both in intelligence tests and attention tests. A trend towards a positive correlation between age at the start of treatment and IQs was confirmed in our study, while there was no evidence of a correlation between IQs and time elapsed from therapy. The role of chemotherapy, radiotherapy and their combination effect in producing neuropsychological sequelae is discussed.