Fig. 1.
The same neuron has been detected in 2 recording sessions 3 days apart. There are various indicators that this has happened. The cross-correlograms are between the target neuron and various other neurons that are present in both sessions. To line them up as we did above, we need to already know which neurons survived from session 1 to session 2. This problem is solved by an iterative procedure as described in Tracking the same neurons.