Scientists decode neuroactivity study "say" your secret

many people's innermost hidden secrets, even with today's state-of-the-art brain imaging technology can not read their mindsBut these people have to be careful, and scientists are working in that directionU.Sscientists have successfully identified a picture that a person has just seen by "decoding" nervous system activity using computer models and functional magnetic resonance imaging (fMRI) scannersThe paper was published online March 5 in the journal NatureSimilar studies have been done before, but they are simple, and the images contained are either too simple or have been arranged by classIn the latest study, Jack Gallant, a neuroscientist at the University of California, Berkeley, and colleagues experimented with a more difficult experiment -- using the brain's visual cortex to determine one of the images the subjects viewed, even if he had never seen it beforeIn the first phase of the experiment, the two subjects (Kendrick Kay and Thomas Naselaris) each looked at 1,750 images of multiple objects and landscapes, while using fMRI scanners to monitor their responses to the visual cortexBased on these data, the researchers divided the visual cortex into small squares and created a mathematical model to show how each cube responds to different visual featuresBy combining hundreds of cubic models, the researchers hope to predict how the visual cortex reacts to any given imageIn the second stage, Kay and Naselaris looked at 120 images they had never seen before and recorded the activity of their visual cortex with an fMRI scannerThe researchers compared the recorded activity with the activity predicted by the model and found that Naselaris's 120 picture models predicted 110 pairs and Kay's 120 pairs of 86When Naselaris again observed 1,000 new images, the model was still able to correctly predict 82% of themBrian Wandell, a neuroscientist at Stanford University in the Us, says the model is a big improvement in the hard-won discovery of the vision system"It applies our knowledge of the brain, to some extent, much more profound than some other experiments, " he said"
but Gallant says that doesn't mean a brain scanner that can "read the heart" is coming up The model can only identify known images, and so far no computer model has been able to use fMRI data to reconstruct what people really see, and may be able to reconstruct the visual content of dreams and memories in the future, but this is also a very distant thing Gallant joked, in other words, that there is still time for some one to wash his mind and re-act (Mei Jin)