The findings are featured on the cover of the journal Cancer Cell • The authors of the study, from the Spanish National Research Council (CSIC) and the Spanish National Cancer Research Centre (CNIO), suggest that cognitive loss in patients with brain metastases may be due to the interference that cancer produces in neuronal circuits. • When cancer spreads in the brain, it changes the brain’s chemistry, interfering with the communication between neurons. This is a very different hypothesis from the one previously accepted, with implications for the diagnosis and treatment of brain metastases. © Atlas / CNIO