This is a prospective study by the group from National Cancer Center, Korea, examining the neuropsychological functioning of patients with varying types of BTs at different time points: before, during, and after proton beam therapy. 98 patients with posterior fossa tumors (PFTs; n = 33), germ cell tumors (GCTs; n = 52), and other supratentorial tumors (STTs; n = 13) underwent baseline neuropsychological assessments and 57 patients underwent follow-up assessments at different time points pre, during and after proton treatment. The study reported significantly lower performance intelligence quotient (PIQ) and processing speed (PS) scores in all groups at baseline. Over time, global IQ scores were stable in all groups. In the PFT group however, verbal comprehension, attention, and PS improved over time, whereas in the GCT group, verbal IQ scores declined significantly, and psychological problems worsened over time, which were correlated with poorer neurocognitive function at 3-5 years after treatment. In the STT group, no significant changes were observed. The authors suggested that early cognitive treatment tailored to the tumor type could be beneficial.