This image shows active neurons (red) in layer 2/3 of mouse primary visual cortex, along with functional connections (red lines) between the neurons. The top and bottom neurons were identified as pattern completion neurons using a graphical model called conditional random fields (CRFs). Pattern completion neurons are able to recall a neuronal ensemble; note that the two identified here are functionally connected with all the other neurons in the image. For more information, see the article by Carrillo-Reid. (pages 8577–8588). Image credit: Luis Carrillo-Reid.