Neuroscientist Rafael Yuste describes experiments in which his team decoded visual signals in mice and then used lasers to recreate those signals directly in their brains. The work made mice behave as if they were seeing moving images that were not actually present, illustrating both the potential of brain-computer technology and the ethical concerns around manipulating perception.

The research used projected moving bars to associate different visual patterns with drinking behaviour, then monitored the corresponding neurons through the skull. A second holographic laser system activated those same neurons, producing licking responses indistinguishable from those prompted by real images. The article argues that advances in fMRI and machine learning are also making human brain activity increasingly interpretable, including emotions and viewed imagery.